text:
Patent US6606641 - System for varying the dynamic range of coefficients in a digital filter - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inPatentsA digital filter includes a plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a gain that is used by each of the plurality of filter cells, and to multiply input data by the adjusted coefficient in...http://www.google.com/patents/US6606641?utm_source=gb-gplus-sharePatent US6606641 - System for varying the dynamic range of coefficients in a digital filterAdvanced Patent SearchTry the new Google Patents, with machine-classified Google Scholar results, and Japanese and South Korean patents.Publication numberUS6606641 B1Publication typeGrantApplication numberUS 09/062,941Publication dateAug 12, 2003Filing dateApr 20, 1998Priority dateApr 20, 1998Fee statusPaidAlso published asDE69930906D1, DE69930906T2, EP0990305A1, EP0990305B1, WO1999054996A1Publication number062941, 09062941, US 6606641 B1, US 6606641B1, US-B1-6606641, US6606641 B1, US6606641B1InventorsKarl Wittig, Gene TurkenichOriginal AssigneeKoninklijke Philips Electronics N.V.Export CitationBiBTeX, EndNote, RefManPatent Citations (22), Non-Patent Citations (1), Referenced by (5), Classifications (14), Legal Events (7) External Links: USPTO, USPTO Assignment, EspacenetSystem for varying the dynamic range of coefficients in a digital filter
US 6606641 B1Abstract
A digital filter includes a plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a gain that is used by each of the plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a filter cell output. An adder circuit generates a filter output by adding filter cell outputs from each of the plurality of filter cells, and an inverse gain circuit adjusts the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells.
What is claimed is: 1. A digital filter comprising:
a plurality of filter cells, each of the plurality of filter cells including circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a gain that is used by each of the plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a filter cell output; an adder circuit which generates a filter output by adding filter cell outputs from each of the plurality of filter cells; and an inverse gain circuit which adjusts the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells. 2. A digital filter according to claim 1, further comprising a gain control circuit to determine the gain based on a coefficient of the plurality of filter cells having a highest order nonzero magnitude bit.
3. A digital filter according to claim 2, wherein each of the plurality of filter cells includes a multiplier circuit to multiply the input data by the adjusted coefficient; and
wherein the gain is determined so that the adjusted coefficient in each filter cell occupies an input range of the multiplier circuit for the filter cell. 4. A digital filter according to claim 3, wherein each of the plurality of filter cells includes a gain adjusting circuit which adjusts the coefficient for the filter cell by shifting bits comprising the coefficient such that in the filter cell having a largest coefficient from among the plurality of filter cells a highest order nonzero bit of the coefficient is in a most significant bit position of an input to the multiplier circuit.
5. A digital filter according to claim 4, wherein the gain adjusting circuit comprises a barrel shifter.
6. A digital filter according to claim 5, wherein the barrel shifter is implemented using a matrix of pass transistors.
7. A digital filter according to claim 2, wherein each of the plurality of filter cells comprises a coefficient adaptation circuit to determine the coefficient for the filter cell, the adaptation circuit updating the coefficient periodically based on data relating to the input data.
8. A digital filter according to claim 7, wherein the gain control circuit varies the gain in accordance with updates in coefficients for the plurality of filter cells.
9. A digital filter according to claim 1, wherein the inverse gain circuit comprises a barrel shifter.
10. A method of filtering input data using a digital filter comprised of a plurality of filter cells, each of the plurality of filter cells for generating a filter cell output based on input data and a coefficient, the method comprising the steps of:
a coefficient determining step for determining a coefficient of each of the plurality of filter cells; a coefficient adjusting step for adjusting the coefficient of each filter cell in accordance with a gain that is used by each of the plurality of filter cells; a multiplying step for multiplying input data in each filter cell by an adjusted coefficient so as to generate a filter cell output for each filter cell; an adding step for adding filter cell outputs from each of the plurality of filter cells so as to generate a filter output; and an output adjusting step for adjusting the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells. 11. A method according to claim 10, further comprising a gain determining step for determining the gain that is used by each of the plurality of filter cells based on a coefficient of the plurality of filter cells having a highest order nonzero magnitude bit.
12. A method according to claim 11, wherein the multiplying step is performed in each of the plurality of filter cells using a multiplier circuit which multiplies input data by an adjusted coefficient; and
wherein the gain determining step determines the gain so that the adjusted coefficient in each filter cell occupies an input range of the multiplier circuit for the filter cell. 13. A method according to claim 12, wherein the coefficient adjusting step adjusts the coefficient for the filter cell by shifting bits comprising the coefficient such that in the filter cell having a largest coefficient from among the plurality of filter cells a highest order nonzero bit of the coefficient is in a most significant bit position of an input to the multiplier circuit.
14. A method according to claim 13, wherein the coefficient adjusting step is performed using a barrel shifter.
15. A method according to claim 14, wherein the barrel shifter is implemented using a matrix of pass transistors.
16. A method according to claim 11, wherein the coefficient determining step determines the coefficient for each filter cell by updating the coefficient periodically based on data relating to input data for the filter cell.
17. A method according to claim 16, wherein the gain determining step varies the gain in accordance with updates in coefficients for the plurality of filter cells.
18. A method according to claim 10, wherein the output adjusting step is performed using a barrel shifter.
19. A digital filter comprising:
a first plurality of filter cells, each of the first plurality of filter cells including circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a first gain that is used by each of the first plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a first filter cell output; a first adder circuit which generates a first output by adding first filter cell outputs from each of the first plurality of filter cells; a first inverse gain circuit which generates a first adjusted output by adjusting the first output in accordance with an inverse of the first gain used to adjust the coefficients of the first plurality of filter cells; a second plurality of filter cells, each of the second plurality of filter cells including circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a second gain that is used by each of the second plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a second filter cell output; a second adder circuit which generates a second output by adding second filter cell outputs from each of the second plurality of filter cells; a second inverse gain circuit which generates a second adjusted output by adjusting the second output in accordance with an inverse of the second gain used to adjust the coefficients of the second plurality of filter cells; and a third adder circuit which adds the first adjusted output and the second adjusted output in order to generate a filter output for the digital filter. 20. A digital filter comprising:
a plurality of filter cells, each of the plurality of filter cells including circuitry to determine a plurality of coefficients for the filter cell, to adjust each of the plurality of coefficients in accordance with a gain that is used by each of the plurality of filter cells, and to multiply a corresponding data value input to the filter cell by a corresponding adjusted coefficient in order to generate to generate a filter cell output; an adder circuit which generates a filter output by adding filter cell outputs from each of the plurality of filter cells; and an inverse gain circuit which adjusts the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells.
The present invention is directed to a digital filter which varies the dynamic range of coefficients used therein in order to reduce the size of hardware required to implement the filter. In particular, the invention is directed to a digital filter which adjusts coefficients thereof in accordance with a filter gain, which multiplies each adjusted coefficient by input data and adds the resulting products, and which adjusts the sum of the products in accordance with an inverse of the filter gain.
Conventional digital filters, such as finite impulse response (hereinafter “FIR”) filters, are comprised of a plurality of filter cells, or “tap” cells, arranged in series. Each filter cell includes a data register for storing a sampled data value and a coefficient register which stores a coefficient for that particular cell. In operation, the same sampled data value is input sequentially to each filter cell, and is multiplied by a coefficient for that cell. The results of these multiplications are then output and combined in order to generate the filter's output. In certain types of digital filters, known as “adaptive” filters, adaptation circuit is also included in each filter cell, which is used to update the cell's coefficients based on a variety of factors, such as channel characteristics or the like, that could affect data transmission.
Problems arise in conventional digital filters due to the way in which such filters multiply the coefficients by the input data. More specifically, conventional digital filters, and in particular adaptive digital filters, often require relatively high bit precision. One way in which to obtain such precision is to use floating point arithmetic to effect the foregoing multiplication. However, floating point arithmetic can require excessive amounts of hardware to implement and can be relatively slow. As a result, floating point arithmetic has proven unsuitable for use in many digital filter applications.
Another way in which conventional digital filters obtain high bit precision is to perform the foregoing multiplication using coefficients that have a relatively large number of bits, i.e., coefficients that have a relatively large dynamic range. In order to process such large numbers of bits, however, these conventional digital filters require relatively large multiplier circuits. As a result, such digital filters also can be relatively large in size. This size constraint can be problematic, particularly in devices such as adaptive equalizers, which require tens or even hundreds of filter tap cells. Moreover, the size of the multiplier circuits used in this type of conventional digital filter also decreases the speed at which those filters operate.
Thus, there exists a need for a way to maintain high bit precision in a digital filter without significantly increasing the size and/or amount of circuitry used in the digital filter, and without significantly decreasing the speed of the digital filter.
The present invention addresses the foregoing need by providing a digital filter which adjusts coefficients in accordance with a gain prior to multiplying the coefficients by the input data. For example, in accordance with the invention, a coefficient whose magnitude has a binary representation of “00000111” can be adjusted to “111” by eliminating the first five zeros, without affecting the value of the coefficient. Using adjusted coefficients such as this, less bit precision is required during multiplication, thereby reducing the size of the multiplication circuit required to perform the multiplication, and increasing the speed at which the multiplication is performed. Moreover, in accordance with the invention, a filter output generated based on results of the multiplication is adjusted based on the inverse of the gain used to adjust the coefficients. As a result, high bit precision is maintained by the filter.
Thus, according to one aspect, the present invention is a digital filter that includes a plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a gain that is used by each of the plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a filter cell output. Also included in the digital filter are an adder circuit which generates a filter output by adding filter cell outputs from each of the plurality of filter cells, and an inverse gain circuit which adjusts the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells.
In preferred embodiments of the invention, the digital filter includes a gain control circuit to determine the gain based on a coefficient of the plurality of filter cells having a highest-order nonzero magnitude bit. In these embodiments of the invention, each of the plurality of filter cells includes a multiplier circuit to multiply the input data by the adjusted coefficient in order to generate the filter cell output, and the gain is determined so that the adjusted coefficient in each filter cell occupies an input range of the multiplier circuit for the filter cell. To this end, each of the plurality of filter cells includes a gain adjusting circuit which adjusts the coefficient for the filter cell by shifting bits comprising the coefficient such that a highest order nonzero magnitude bit of the coefficient is in a most significant bit position of an input to the multiplier circuit. By virtue of these features of the invention, it is possible to reduce the bit precision of the coefficient, e.g., by eliminating unnecessary zeros in the binary representation of the coefficient, and to thereby reduce the size of the multiplier circuit used during the multiplication described above.
In particularly preferred embodiments of the invention, the gain adjusting circuit comprises a barrel shifter which is implemented using a matrix of pass transistors. By implementing the barrel shifter using a matrix of pass transistors, the size of the barrel shifter can be reduced, thereby reducing the overall size of the digital filter even further.
According to another aspect, the present invention is a method of filtering input data using a digital filter comprised of a plurality of filter cells, where each of the plurality of filter cells generates a filter cell output based on input data and a coefficient. The method includes a coefficient determining step for determining a coefficient of each of the plurality of filter cells, a coefficient adjusting step for adjusting the coefficient of each filter cell in accordance with a gain that is used by each of the plurality of filter cells, and a multiplying step for multiplying input data in each filter cell by an adjusted coefficient so as to generate a filter cell output for each filter cell. The method also includes an adding step for adding filter cell outputs from each of the plurality of filter cells so as to generate a filter output, and an output adjusting step for adjusting the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells.
By adjusting the coefficient of each filter cell in accordance with a gain that is used by each of the plurality of filter cells, and then subsequently adjusting the filter output in accordance with an inverse of the gain used to adjust the coefficients, the invention is able to maintain bit precision of the filter without using excessive amounts of hardware to do so. Moreover, a digital filter which uses the method described above can be made smaller than, and can operate faster than, its conventional counterparts described above.
According to another aspect, the present invention is a digital filter which includes a first plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a first gain that is used by each of the first plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a first filter cell output. A first adder circuit generates a first output by adding first filter cell outputs from each of the first plurality of filter cells, and a first inverse gain circuit generates a first adjusted output by adjusting the first output in accordance with an inverse of the first gain used to adjust the coefficients of the first plurality of filter cells. Also included in the digital filter are a second plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a second gain that is used by each of the second plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a second filter cell output. A second adder circuit generates a second output by adding second filter cell outputs from each of the second plurality of filter cells, and a second inverse gain circuit generates a second adjusted output by adjusting the second output in accordance with an inverse of the second gain used to adjust the coefficients of the second plurality of filter cells. Finally, a third adder circuit adds the first adjusted output and the second adjusted output in order to generate a filter output for the digital filter.
By virtue of the foregoing features of the invention, it is possible to adjust different coefficients in different groups of filter cells differently, and thereby increase the overall precision of the filter.
According to still another aspect, the present invention is a digital filter which includes a plurality of filter cells, each of which includes circuitry to determine a plurality of coefficients for the filter cell, to adjust each of the plurality of coefficients in accordance with a gain that is used by each of the plurality of filter cells, and to multiply a corresponding data value input to the filter cell by a corresponding adjusted coefficient in order to generate a filter cell output. In the invention, an adder circuit generates a filter output by adding filter cell outputs from each of the plurality of filter cells, and an inverse gain circuit adjusts the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells.
Thus, the foregoing aspect of the invention combines resource sharing with varying coefficients' dynamic ranges. As a result, this aspect of the invention provides even further reductions in hardware, without sacrificing speed or bit precision.
FIG. 1 is a functional block diagram showing an adaptive FIR filter in accordance with a first embodiment of the present invention.
FIG. 2 is a block diagram showing circuitry which may be used to implement the functions shown in FIG. 1.
FIG. 3 is a circuit diagram showing a standard way to implement the unsigned value circuit shown in FIG. 2, together with flip flops from the coefficient register shown in FIG. 1.
FIG. 4 is a circuit diagram showing an alternative way to implement the unsigned value circuit shown in FIG. 2, together with flip flops from the coefficient register shown in FIG. 1.
FIG. 5 shows circuitry used to implement the gain control circuit shown in FIG. 2.
FIG. 6 shows implementation of a barrel shifter using a matrix of pass transistors.
FIG. 7 shows a second embodiment of a digital filter in accordance with the present invention.
FIG. 8 shows a third embodiment of a digital filter in accordance with the present invention.
Initially, it is noted that although the present invention can be used with different types of digital filters, the invention will be described in the context of an adaptive FIR filter. In this regard, FIG. 1 shows an example of an adaptive FIR filter which implements the present invention. As shown in FIG. 1, digital filter 1 includes adder circuit 2, inverse gain circuit 3, and a plurality of identical filter cells 4. Any number of these filter cells may be included in digital filter 1, depending upon the desired functionality of the filter.
Digital filter 1 operates by sampling data from a signal at a predetermined sampling rate, and sequentially shifting the sampled data, labeled 5 in FIG. 1, into each of filter cells 4 in accordance with a sampling clock signal. For example, sampled data 5 is shifted into filter cell 4 a in response to a first sampling clock pulse. Next, when additional data is sampled at a next sampling clock pulse, that additional data is shifted into filter cell 4 a, and the data already in filter cell 4 a (i.e., sampled data 5) is shifted into filter cell 4 b, and so on.
Each of filter cells 4 processes the sampled data within a single period of the sampling clock signal. As described below in more detail, this processing includes determining a coefficient for each of the plurality of filter cells, adjusting the coefficient of each filter cell in accordance with a gain that is used by each of the plurality of filter cells, and multiplying the sampled data input to each filter cell by an adjusted coefficient so as to generate a filter cell output, labeled 6 in FIG. 1, for each filter cell. After the sampled data has been processed by all of filter cells 4 in this manner, resulting filter cell outputs are provided to adder circuit 2. Adder circuit 2 combines filter cell outputs from each of filter cells 4 in order to generate filter output 7 for filter 1. Thereafter inverse gain circuit 3 adjusts filter output 7 in accordance with an inverse of the gain that was used to adjust the coefficients of filter cells 4, and outputs the result.
As shown in FIG. 1, filter cell 4 a, which is identical in structure to the others of filter cells 4, includes data register 9, coefficient register 10, coefficient adaptation circuit 11, gain adjusting circuit 12, and multiplier circuit 14. Data register 9 receives an input data value from an external source (not shown), such as a data line or a previous filter cell. Coefficient register 10 stores a binary value of a coefficient used by the filter cell. Coefficient adaptation circuit 11 determines updated coefficient values and stores these updated coefficient values in coefficient register 10. More specifically, as noted above, filter cell 4 a is an adaptive filter cell, meaning that a coefficient stored therein is updated periodically. Thus, a coefficient in filter cell 4 a may be updated periodically to correct for unwanted changes in the input data value caused, e.g., by changes in a transmission channel used to transmit the data value, and/or to perform correction based on external input 15 which can comprise a filter error or the like.
Multiplier circuit 14 multiplies a data value output from data register 9 by a coefficient which has been adjusted by gain adjusting circuit 12. Specifically, gain adjusting circuit 12 adjusts a coefficient output from coefficient register 10 by applying a variable gain 16 thereto (e.g., by multiplying the coefficient by the gain). In this regard, multiplying a binary coefficient by a power of 2N has the effect of shifting that binary coefficient left by “N” bits. Accordingly, gain 16 which, as described below, is a power of 2N, has the effect of shifting bits of the coefficient output from coefficient register 10 to the left. Preferably, this shift is such that a highest order nonzero magnitude bit (i.e., non-sign bit) of the coefficient is in a most significant bit position of an input to multiplier circuit 14, and such that the adjusted coefficient occupies a full dynamic range (i.e., an input range) of multiplier circuit 14.
By way of example, in a case that multiplier circuit 14 comprises an eight-bit multiplier and the coefficient for the cell has an unsigned bit representation of “0000000011001100”, gain adjusting circuit 12 applies a gain which shifts bits of the coefficient so that the coefficient comprises “11001100”. In this manner, gain adjusting circuit 12 eliminates eight unnecessary zeros from the coefficient. By doing this, the invention is able to replace a relatively large sixteen-bit multiplier circuit with a smaller, eight-bit multiplier circuit, without sacrificing multiplication accuracy. Moreover, since inverse gain circuit 3 adjusts filter output 7 in accordance with an inverse of the gain applied by gain adjusting circuit 12, in this example, the invention is able to maintain sixteen-bit precision. Specifically, the invention is able to maintain sixteen-bit precision by adding eight zeros to high order bit positions of filter output 7.
In the invention, the gain introduced by gain adjusting circuit 12 is variable in response to changes in the filter coefficients. In this regard, FIG. 2 shows specific circuitry, namely gain control circuit 20 and unsigned value circuit 21, which is used to determine the gain. FIG. 2 also shows a representative circuit architecture that is used to perform the other functions described above with respect to FIG. 1. Specifically, FIG. 2 shows barrel shifter 22, which performs the function of gain adjusting circuit 12, and barrel shifter 24, which performs the function of inverse gain circuit 3. A detailed description of the operation of these features is provided below.
More specifically, barrel shifter 22 applies a gain to a coefficient output from coefficient register 10. As is well known in the art, a barrel shifter, such as barrel shifter 22, can provide any amount of gain that corresponds to a power of two. The amount of gain to be applied by barrel shifter 22 is determined by gain control circuit 20. In this regard, since all filter coefficients are enhanced by the same gain in this embodiment of the invention, gain control circuit 20 determines the gain based on the highest order nonzero magnitude bit in the coefficients of filter cells 4. That is, since barrel shifter 22 shifts bits in the coefficient so that the highest order nonzero magnitude bit in the coefficient is one, gain control circuit 22 determines the amount of bit shift which is to be performed on all coefficients based on the amount of bits that a coefficient having a highest order nonzero magnitude bit can be shifted without affecting its value. For example, if the coefficients comprise unsigned “00001101”, “00110011”, and “00000011”, gain control circuit 20 will identify “00110011” as having the highest order nonzero magnitude bit, and thus select a gain which will shift that coefficient, as well as the other two coefficients by two zeros to the left (since there are zeros in the 128's and 256's positions of the “00110011” coefficient). Specific circuitry for effecting this operation is described below.
Since the coefficients are represented by binary numbers, in a case where there are no sign values in the coefficients (i.e., all the coefficients are positive), the task of locating a coefficient having a highest order nonzero bit comprises merely finding the highest-order nonzero bit among all of the coefficients in filter 1. In cases where the coefficients have sign values, and are represented using conventional two's complement format, the complexity of this task is increased due to the presence of a sign bit in the most significant bit (“MSB”) position. Accordingly, the present invention provides unsigned value circuit 21 to address the problem of the sign bit. In operation, unsigned value circuit 21 obtains a coefficient from coefficient register 10, and then determines the magnitude (i.e., the absolute value) of the coefficient by a bitwise inversion of the coefficient in a case that a sign bit for the coefficient indicates that the coefficient is a negative number.
In this regard, unsigned value circuit 21 may include standard logic elements to perform the bitwise inversion of magnitude bits (i.e., non-sign bits) for the coefficient described above. FIG. 3 shows such an implementation. That is, FIG. 3 shows an implementation of unsigned value circuit 21 using exclusive-OR gates 29 and inverters 30. In operation, exclusive-OR gates 29 output the magnitude of the data stored in flip flops 27 (which comprise coefficient register 10) by virtue of an exclusive-OR operation performed between the sign bit stored in flip flop 27 a and the magnitude bits stored in flip flops 27 b to 27 e. In this embodiment, inverters 30 are provided so as to invert the magnitude of the data output from exclusive-OR gates 29. This is done because, in the present embodiment of the invention, coefficient magnitude bus 38 is an “active-low” bus, as opposed to an “active-high” bus. In cases where an active-high bus is used, no inverters would be required.
As shown in FIG. 3, since the filter coefficients are stored in coefficient register 10 using standard flip flops 27, each flip flop will have both an uncomplemented and a complemented coefficient data output. Consequently, exclusive-OR gates 29 may be replaced by a two-to-one multiplexer (not shown), which selects between two outputs according to a value of a sign bit. Such a multiplexer may be implemented using conventional logic gates or, alternatively, may be implemented using two pass transistors in the manner shown in FIG. 4.
In this regard, FIG. 4 shows a two-pass-transistor implementation of unsigned value circuit 21, together with flip flops 27 from coefficient register 10. Taking transistors 34, 35 and 36 as examples, gate 34 a of transistor 34 is connected to the complemented sign bit output of flip flop 27 a, and gate 35 a of transistor 35 is connected to the uncomplemented sign bit output of flip flop 27 a. Drains 34 b and 35 b of transistors 34 and 35, respectively, are connected together in the configuration shown in FIG. 4, so as to form a node that is always connected to one of the outputs of flip flop 27 b. Which output the node is connected to depends upon the coefficient's sign bit stored in flip flop 27 a. A magnitude bit (in this case, the MSB) may then be output from flip flop 27 b to coefficient bus 38 (see FIG. 2) via this node. Specifically, the magnitude bit is output via gate 36 a of transistor 36 having source 36 b that is grounded and drain 36 c that is connected to all other drains on coefficient magnitude bus 38 and to pull-up-resistor 39. The remaining magnitude bits that are stored in flip flops 27 c to 27 e are also output to coefficient magnitude bus 38 in this manner.
Thus, following processing by unsigned value circuit 21, an unsigned coefficient is output to coefficient magnitude bus 38. Determination of the highest order bit of this coefficient is then performed by gain control circuit 20, which can comprise a priority encoder or the like. Specifically, gain control circuit 20 determines a coefficient value having a highest order nonzero bit, and thus the number of bits by which all coefficients, as well as the filter output, must be shifted. FIG. 5 shows circuitry which may be used to implement gain control circuit 20 in this embodiment of the invention.
In this regard, as shown in FIG. 5, gain control circuit 20 includes a plurality of AND gates and inverters, into which are input binary coefficient data output from unsigned value circuit 21. The logic gates shown in FIG. 5 are configured to ensure that, for any input, a single “1” is output, together with a plurality of “0's”. The “Shift” line on which the single “1” is output corresponds the amount of shift required for the input coefficient. For example, for “Shift 0”, no bits are to be shifted, for “Shift 1”, the bits are to be shifted one to the left, for “Shift 2”, the bits are to be shifted two to the left, and so on.
The case of a negative coefficient having an inverted magnitude of “0001”, in which “0” is the MSB and “1” is the least significant bit (“LSB”), can be used to illustrate the operation of the circuit shown in FIG. 5. More specifically, in this case “0001” is input to ports 40, 41, 42 and 43. As a result, the output of “Shift 0” is “1”, and the outputs of “Shift 1”, “Shift 2”, and “Shift 3” are all “0's”. Since the “0001” is inverted, as described above, the actual value of the coefficient in this case is really “1110”. Thus, a “1” at “Shift 0”, which means that no shift of the data is to be performed, is correct since bits in “1110” should not be shifted. Table 1 shown below provides examples of inputs to gain control circuit 20 for four-bit, nonzero coefficients, and corresponding shift outputs produced thereby.
Gain control circuit 20 also includes circuitry (not shown) to determine the highest-order nonzero bit in the coefficients of digital filter 1 based on the shift amounts output from the circuit shown in FIG. 5. For example, the shift amounts for all coefficients in digital filter 1 can be logically “OR-ed” in order to find the shift amount for all coefficients in the filter.
As an alternative to the circuitry described above, in a case that coefficients in the filter all have positive values, (i.e., there are no sign bits), the coefficients may simply be output from coefficient register 10 to coefficient magnitude bus 38 without going through unsigned value circuit 21. Thereafter, gain control circuit 20, which in this case may simply comprise plurality of “OR” gates, finds the highest-order nonzero bit by performing a logical OR operation on same order bits from each coefficient. The bit shift amount corresponding to a coefficient having a highest-order nonzero bit is then selected and output based on this operation. One method of implementing this logical OR operation, as well as that described above, is through a distributed means, such as a “wired-OR” of the bits (or a “wired-AND” of the inverted bits).
Once a bit shift amount (i.e., a gain) has been determined, the bit shift amount is then provided to barrel shifters 22 and 24, as shown in FIG. 2. In this regard, as noted above, coefficients in filter cells 4 are shifted by the same amount. Accordingly, as shown in FIG. 2, the shift amount is provided to each of shift cells 4. Barrel shifter 22 attenuates a coefficient provided from coefficient register 10 by the bit shift amount provided from gain control circuit 20. That is, barrel shifter 22 shifts the coefficient provided from coefficient register 10 left by an amount equal to the bit shift amount provided by gain control circuit 20. As described above, this results in the elimination of unnecessary bits from the coefficient and thus permits a multiplication circuit having a smaller dynamic range to be used in each filter cell.
After a coefficient from coefficient register 10 has been adjusted by the requisite shift amount, that “adjusted” coefficient is then multiplied by an input data value from data register 9. The output of this multiplication comprises the filter cell output 6, and is provided to adder circuit 2. In preferred embodiments of the invention, the shift amount (i.e., the gain) is selected so that the adjusted coefficient in each filter cell occupies an entire input range of the multiplier circuit for that filter cell. Thus, in the case that an eight-bit multiplier is used, in these embodiments of the invention, the gain should be selected so as to ensure that there are eight bits of coefficient data provided to the multiplier circuit. This can be implemented in gain control circuit 20 by including circuitry therein to perform sign extension by adding zeros for positive numbers or ones for negative numbers to unoccupied high order bit positions of coefficient values that do not have the requisite number of bits.
As described above, adder circuit 2 adds filter cell outputs from all of filter cells 4 in order to generate filter output 7 for digital filter 1. Thereafter, barrel shifter 24 shifts the filter output, i.e., the sum of the outputs of filter cells 4, by a gain which is the inverse of that used by barrel shifter 22. That is, barrel shifter 24 performs sign extension on the filter output so as to maintain a necessary bit precision of the filter. For example, if the barrel shifters in filter cells 4 (e.g., barrel shifter 22) remove three most significant bits from the filter coefficients, barrel shifter 24 adds three sign extension bits to the high order bit positions of filter output 7.
Barrel shifters 22 and 24 may be implemented using standard digital logic gates. However, due to the large number of logic gates required in logic gate configurations, the present invention preferably implements barrel shifters 22 and 24 using a matrix of pass transistors. An example of well-known barrel shifter configuration using a matrix of pass transistors is shown in FIG. 6. By using a barrel shifter configured in the manner shown in FIG. 6, the invention is able to reduce even further the amount of hardware required to implement digital filter 1. This, in turn, reduces signal propagation delay, thereby increasing the speed of digital filter 1.
A second embodiment of a digital filter in accordance with the present invention is shown in FIG. 7. This embodiment is a digital filter which includes a first plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a first gain that is used by each of the first plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a first filter cell output. A first adder circuit generates a first output by adding first filter cell outputs from each of the first plurality of filter cells, and a first inverse gain circuit generates a first adjusted output by adjusting the first output in accordance with an inverse of the first gain used to adjust the coefficients of the first plurality of filter cells. Also included in the digital filter are a second plurality of filter cells, each of which includes circuitry to determine a coefficient for the filter cell, to adjust the coefficient in accordance with a second gain that is used by each of the second plurality of filter cells, and to multiply input data by the adjusted coefficient in order to generate a second filter cell output. A second adder circuit generates a second output by adding second filter cell outputs from each of the second plurality of filter cells, and a second inverse gain circuit generates a second adjusted output by adjusting the second output in accordance with an inverse of the second gain used to adjust the coefficients of the second plurality of filter cells. Finally, a third adder circuit adds the first adjusted output and the second adjusted output in order to generate a filter output for the digital filter.
Thus, with reference to FIG. 7, digital filter 49 includes first filter circuit 50 and second filter circuit 51, both of which are identical in structure and function to digital filter 1 shown in FIG. 2. Digital filter 49 also includes adder circuit 52, which adds outputs from the first and second filter circuits. Using the circuit configuration shown in FIG. 7, it is possible to increase the overall precision of the digital filter.
More specifically, in accordance with the invention, a first gain (i.e., a first shift amount) can be determined for first filter circuit 50. This first gain can then be used to adjust coefficients in each of first filter cells 54 in first filter circuit 50. Thereafter, an inverse of the first filter gain can then be used to adjust first filter output 55 using a first inverse gain circuit such as barrel shifter 56. A second gain (i.e., a second shift amount), which may be the same or different from the first gain, can be determined for second filter circuit 51. This second gain can then be used to adjust coefficients in each of second filter cells 57 in second filter circuit 51. Thereafter, an inverse of the second filter gain can then be used to adjust second filter output 59 using a second inverse gain circuit such as barrel shifter 60. Adjusted outputs 61 and 62 are then added using adder circuit 52 in order to generate an output for digital filter 49.
By using different gains for different parts of a filter, this embodiment of the invention makes it possible to attenuate coefficients in different groups of filter cells differently. This can lead to a further reduction in the amount of hardware needed to implement the digital filter for a given overall filter precision. For example, in the case of a ten-filter cell, coefficients in the first five cells may have more excess zeros in high order bit positions than the second five filter cells. Thus, for example, coefficients in the first five filter cells may be adjusted so that these cells can use an eight-bit multiplier and coefficients in the second five cells may be adjusted so that these cells can use a sixteen-bit multiplier. Since an eight-bit multiplier requires less hardware to implement than a sixteen-bit multiplier, and can be used for five of the ten filter cells, the overall size of the digital filter can be decreased even further relative to that of its conventional counterparts.
A third embodiment of a digital filter in accordance with the present invention is shown in FIG. 8. Specifically, this embodiment is a digital filter which includes a plurality of filter cells, each of which includes circuitry to determine a plurality of coefficients for the filter cell, to adjust each of the plurality of coefficients in accordance with a gain that is used by each of the plurality of filter cells, and to multiply a plurality of data values input to the filter cell by corresponding adjusted coefficients in order to generate a filter cell output. In the invention, an adder circuit generates a filter output by adding filter cell outputs from each of the plurality of filter cells, and an inverse gain circuit adjusts the filter output in accordance with an inverse of the gain used to adjust the coefficients of the plurality of filter cells.
The subject embodiment of the invention combines the advantages of the first embodiment described above with the advantages of resource sharing in a single filter cell. In general, resource sharing refers to sharing hardware circuitry, most often a multiplier circuit, within a single filter cell so as to reduce the overall amount of hardware required to implement the filter and, consequently, to reduce the size of the filter. In this regard, the invention may be implemented in a conventional resource sharing arrangement, in which multiplexers are used in a filter cell in order to multiply different filter coefficients by different data values using the same multiplication circuit. Alternatively, the invention may be implemented in the resource sharing system described in U.S. patent application Ser. No. 09/031,698, entitled “System For Sharing Resources In A Digital Filter” (Assignee: Philips Electronics North America Corp.; Inventors: Karl Wittig and Gene Turkenich) filed Feb. 27, 1998, now U.S. Pat. No. 6,108,681, the contents of which are hereby incorporated by reference into the subject application as if set forth herein in full.
In this regard, in the resource sharing system described in U.S. patent application Ser. No. 09/031,698, each filter cell stores more than one input data value and more than one coefficient, but uses a single multiplier circuit to multiply coefficients by data values. Moreover, each of these filter cells uses the same adaptation circuitry to update plural coefficient values, thereby further reducing the amount of hardware required in the filter. FIG. 8 shows an example of a digital filter in accordance with this embodiment of the invention. Specifically, FIG. 8 shows a digital filter which implements both resource sharing and coefficient dynamic range varying of the type described above in the first two embodiments. As shown in FIG. 8, filter 70 includes filter cells 71. Each of these filter cells includes an input register 72, a multiplexer 73, data registers 74, a multiplier circuit 75, coefficient registers 76, logic stages 77, 78, 79 and 80, barrel shifter 81, and unsigned value circuit 82.
Barrel shifter 81 and unsigned value circuit 82 operate in the same manner as barrel shifter 22 and unsigned value circuit 21 described above with respect to FIG. 2. The same is true of gain control circuit 85, barrel shifter 86, and adder circuit 87, which are also shown in FIG. 8. That is, these components operate in substantially the same manner as gain control circuit 20, barrel shifter 24, and adder circuit 2 described above with respect to FIG. 2. Detailed descriptions of these components are therefore here omitted for the sake of brevity. It is worth noting, however, that, in the example shown in FIG. 8, adder 87 must operate four times faster than adder 2, since adder 87 is receiving filter outputs at four times the rate that adder 2 receives filter outputs. In this regard, in general, in a case that there are “N” filter coefficients per filter cell, in the third embodiment, the adder must operation “N” times as fast as adder 2 of the first embodiment. Moreover, this embodiment of the invention includes accumulator 100, which adds the outputs of the filter cells together, stores the sum of the products, and outputs the sum of the products in response to a clock pulse.
The remaining components shown in FIG. 8 enable sharing of both multiplier circuit 75 and coefficient circuitry used to update coefficients in coefficient registers 76. To this end, input register 72 is arranged in series with multiplexer 73 and data registers 74. Both input register 72 and data registers 74 can comprise conventional shift registers, which shift data in response to a clock signal. In this regard, as described in more detail below, input register 72 shifts data in response to the sampling clock signal noted above. In contrast, data registers 74 shift data in response to a circulation clock signal, which has a frequency that is a multiple of the frequency of the sampling clock signal. This arrangement provides for multiple shifting of each of data registers 74 for every single shift of input register 72.
Data register 74 a outputs a data value to multiplier circuit 75 at each circulation clock pulse. As shown in FIG. 8, that same data value is fed back to multiplexer 73 via feedback path 97. Multiplexer 73 also receives selection signal 88 and an output from input register 72. Selection signal 88 causes multiplexer 73 to shift data from register 72 during sampling clock pulses, and causes multiplexer 73 to shift data from feedback path 97 during circulation clock pulses. By virtue of this arrangement, during circulation clock pulses, data values circulate within data registers 74. However, at each sampling clock pulse, an additional data value from input register 72 is shifted into data registers 74, where the additional data value is circulated. Thus, to summarize, data registers 74 circulate a first set of data values for a predetermined time, and, following the predetermined time, data registers 74 circulate a second set of data values (which includes the additional data value) for the predetermined time, and so on.
In this regard, data registers 74 are designed to circulate the same number of data values. Accordingly, each time an additional data value is input into data registers 74, one of the data values already within data registers 74 is removed. Specifically, the data value in feedback path 97 (i.e., the data value which was last output to multiplier circuit 75) is removed, since that data value is not input back into data registers 74. Since only one data value is removed per sampling clock period, data registers 74 generally circulate a data value for a plurality of sampling clock periods before that data value is removed. The exception to this general rule is the case in which a single data value is circulated in a single data register. In this case, the data value only needs to be circulated for one sampling clock period.
Coefficient registers 76 are arranged to circulate a plurality of coefficient values that correspond to a plurality of coefficients, so that each of the plurality of coefficient values is output once during a predetermined period. More specifically, coefficient values are shifted among coefficient registers 76 such that, at a predetermined period, which preferably corresponds to a period of the circulation clock signal, coefficient register 76 a outputs a coefficient to barrel shifter 81. In turn, barrel shifter 81 summarily adjusts that coefficient in accordance with a gain received from gain control circuit 85, and outputs the adjusted coefficient to multiplier circuit 75. Thus, at each period of the circulation clock signal, multiplier circuit 75 receives a data value from data register 74 a and an adjusted coefficient from barrel shifter 81. At this time, multiplier circuit 75 multiplies these two values to generate and output a product. It is noted that although a multiplier circuit is described, any type of circuit may be used in the embodiments of the invention described herein depending, of course, upon the type of filter cell in which the invention is implemented, among other things.
Regarding coefficient registers 76, as shown in FIG. 8, coefficient registers 76 circulate coefficient values by feeding a coefficient output to barrel shifter 81 back along feedback path 90. This arrangement permits the same coefficients to circulate among coefficient registers 76, thereby making it possible for those coefficients to be shared by data values in data registers 74. That is, as described above, data registers 74 circulate a data value for a plurality of sampling clock periods before that data value is removed. As a result, the same data value is output several times to multiplier circuit 75 over several sampling clock signal periods. Each time that the same data value is output to multiplier circuit 75, a different coefficient value is output thereto via barrel shifter 81. As a result, each data value is multiplied by each coefficient.
In the preferred embodiment of the invention shown in FIG. 8, a plurality of logic stages 77, 78, 79 and 80 are arranged among coefficient registers 76. These logic stages receive external inputs 92, 93, 94 and 95, respectively, and, if necessary, calculate updated coefficients values corresponding to coefficients output by coefficient registers 76. More specifically, as noted above, filter cell 71 a is an adaptive filter cell, meaning that coefficients therein may be updated periodically to correct unwanted changes in the data values caused, e.g., by changes in the transmission channel or the like. In the present invention, these updates are made via logic stages 77 to 80, where external inputs 92 to 95 can comprise filter error (i.e., a difference between expected and actual filter outputs) or the like.
Thus, in the present invention, coefficient computation is “broken up” into separate pipe-line stages, each of which is performed between appropriate coefficient registers. Accordingly, in these embodiments of the invention, coefficient values in coefficient registers 76 b, 76 c and 76 d do not necessarily comprise actual coefficients, hence the “prime” indications on C2, C3 and C4. Rather, the coefficient values in these coefficient registers may represent intermediate values of the computation of the actual coefficients. This feature of the invention is advantageous, since it allows coefficient circulating and updating to be performed simultaneously, thereby further reducing the amount of hardware required to implement filter cell 71 a. In preferred embodiments of the invention, logic stages 77 to 80 update the coefficients using the well-known least-mean-squares algorithm. However, it is noted that the invention is not limited to updating the coefficients using this algorithm, and that any such algorithm may be used.
Thus, except for the resource sharing aspect described above, and minor timing considerations, the third embodiment of the invention operates in a manner which is similar to that of the first embodiment. In this regard, it is noted that the second embodiment of the invention can also be implemented using filter cells that implement resource sharing of the type described in the third embodiment. In such an embodiment, it is possible to achieve substantial overall hardware reductions in the digital filter, without reducing the filter's speed of operation.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS4615026 *Jan 20, 1984Sep 30, 1986Rca CorporationDigital FIR filters with enhanced tap weight resolutionUS4972483 *Sep 23, 1988Nov 20, 1990Newbridge Networks CorporationSpeech processing system using adaptive vector quantizationUS5029121 *Apr 20, 1990Jul 2, 1991Fuji Xerox Co., Ltd.Digital filter processing deviceUS5029217 *Apr 3, 1989Jul 2, 1991Harold AntinDigital hearing enhancement apparatusUS5079734 *Apr 30, 1990Jan 7, 1992Harris CorporationDigital decimation filterUS5172411 *Mar 27, 1991Dec 15, 1992Siemens AktiengesellschaftTwo-wire/four-wire converterUS5216589 *Sep 26, 1990Jun 1, 1993Canon Kabushiki KaishaAdaptive apparatusUS5233549Apr 21, 1992Aug 3, 1993Loral Aerospace Corp.Reduced quantization error FIR filterUS5339264Jul 27, 1992Aug 16, 1994Tektronix, Inc.Symmetric transposed FIR digital filterUS5381359 *Aug 27, 1992Jan 10, 1995Quantum CorporationAdaptation and training of digital finite impulse response filter within PRML sampling data detection channelUS5617344 *Jun 1, 1995Apr 1, 1997Harris Corp.Fixed coefficient high decimation filterUS5619711 *Jun 29, 1994Apr 8, 1997Motorola, Inc.Method and data processing system for arbitrary precision on numbersUS5802399 *Jul 12, 1996Sep 1, 1998Sharp Kabushiki KaishaData transfer control unit for reducing memory requirements in an information processor by converting bit width of data being transferred between memory and processing partsUS5838598 *Dec 12, 1995Nov 17, 1998Analog Devices, Inc.Method and apparatus for gain correction of a sigma-delta converterUS5852667 *Jul 1, 1996Dec 22, 1998Pan; JianhuaDigital feed-forward active noise control systemUS5854756 *Aug 15, 1996Dec 29, 1998Racal-Datacom LimitedDigital filtersUS5867065 *May 7, 1997Feb 2, 1999Glenayre Electronics, Inc.Frequency selective predistortion in a linear transmitterUS5884092 *Oct 4, 1996Mar 16, 1999Hitachi, Ltd.System for maintaining fixed-point data alignment within a combination CPU and DSP systemUS6018689 *Nov 6, 1997Jan 25, 2000Nissan Motor Co., Ltd.Active vibration reducing apparatus and method for identifying transfer function in active vibration reducing apparatusUS6108681Feb 27, 1998Aug 22, 2000Philips Electronics North America CorporationSystem for sharing resources in a digital filterUS6271782 *Apr 3, 2000Aug 7, 2001Jesper Steensgaard-MadsenDelta-sigma A/D converterEP0813301A1Jun 10, 1996Dec 17, 1997TOSHIBA Electronics Europe GmbHAdaptive digital filter* Cited by examinerNon-Patent CitationsReference1PHA 23,373, U.S. Ser. No. 09/031,698, Filed: Feb. 27, 1998.Referenced byCiting PatentFiling datePublication dateApplicantTitleUS6985522 *Dec 21, 2000Jan 10, 2006Nec CorporationVariable-gain digital filterUS7535954 *Sep 11, 2003May 19, 2009Samsung Electronics Co., Ltd.Method and apparatus for performing channel equalization in communication systemsUS20010005396 *Dec 21, 2000Jun 28, 2001Nec CorporationVariable-Gain digital filterUS20040101075 *Sep 11, 2003May 27, 2004Kim Min-HoMethod and apparatus for performing channel equalization in communication systemsUS20150162896 *Apr 19, 2012Jun 11, 2015Nec CorporationDigital filter circuit* Cited by examinerClassifications U.S. Classification708/319, 708/322, 708/315, 708/400, 708/300, 708/323, 708/301International ClassificationH03H21/00, H03H17/02, H03H17/06Cooperative ClassificationH03H17/06, H03H17/0223European ClassificationH03H17/02E, H03H17/06Legal EventsDateCodeEventDescriptionApr 20, 1998ASAssignmentOwner name: U.S. PHILIPS CORPORATION, NEW YORKFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WITTIG, KARL;TURKENICH, GENE;REEL/FRAME:009122/0792Effective date: 19980416Jan 14, 2003ASAssignmentOwner name: KONINKLIJKE PHILIPS ELECTRONICS N.V., NETHERLANDSFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:U.S. PHILIPS CORPORATION;REEL/FRAME:013659/0461Effective date: 20021030Jan 25, 2007FPAYFee paymentYear of fee payment: 4Feb 4, 2009ASAssignmentOwner name: IPG ELECTRONICS 503 LIMITEDFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KONINKLIJKE PHILIPS ELECTRONICS N.V.;REEL/FRAME:022203/0791Effective date: 20090130Owner name: IPG ELECTRONICS 503 LIMITED, GUERNSEYFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KONINKLIJKE PHILIPS ELECTRONICS N.V.;REEL/FRAME:022203/0791Effective date: 20090130Feb 7, 2011FPAYFee paymentYear of fee payment: 8Jul 20, 2012ASAssignmentOwner name: PENDRAGON WIRELESS LLC, WASHINGTONFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:IPG ELECTRONICS 503 LIMITED;REEL/FRAME:028594/0224Effective date: 20120410Feb 5, 2015FPAYFee paymentYear of fee payment: 12RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services


text:
Teheran and Snitker react to Tuesday's lossHere are Brian Snitker and Julio Teheran talking about Tuesday's tough loss to Milwaukee.by Bill ShanksAtlanta DugoutWednesday at 7:43 AMTyler Flowers InterviewTyler Flowers talks about what it's like to catch Atlanta's young pitchers.by Bill ShanksAtlanta DugoutWednesday at 7:38 AMIan Krol InterviewBill Shanks talked with Atlanta Braves' reliever Ian Krol.by Bill ShanksAtlanta DugoutWednesday at 7:32 AMFull coverage of the Fredi Gonzalez firingHere's Bill Shanks analyzing the decision by the Braves to fire Fredi Gonzalez and hire Brian Snitker.by Bill ShanksAtlanta Dugout05/18/2016From the NetworkKick Off a Great Summer with Scout!Memorial Day is finally here, which means it's time to gear up for a great summer by utilizing the benefits that come with a Scout membership.by StaffScoutYesterday at 8:45 AMJim Callis InterviewBill Shanks talks with MLB.com's Jim Callis about the upcoming June Draft.by Bill ShanksAtlanta Dugout05/18/2016Braves make two right decisionsThe Braves made two solid decisions Tuesday.by Bill ShanksAtlanta Dugout05/18/2016Face it - the 1990s are over!The Braves are rebuilding. It's time for some to realize this is no longer the 1990s Braves. Those days are over.by Bill ShanksAtlanta Dugout05/17/2016Braves fire Gonzalez and promote SnitkerThe Atlanta Braves have fired manager Fredi Gonzalez. His replacement will be Brian Snitker.by Bill ShanksAtlanta Dugout05/17/2016Braves lose first game of series vs. PiratesThe losing continues, as the Braves lose game one of the series in Pittsburgh.by Bill ShanksAtlanta Dugout05/17/2016Braves need to trade Julio Teheran...soon!The Braves should learn from the mistakes of the past and not wait too long to trade Julio Teheran.by Bill ShanksAtlanta Dugout05/16/2016Foltynewicz turning a corner as a starterMike Foltynewicz could really become a huge part of the Atlanta rotation if he continues to pitch the way he did Saturday in Kansas City.by Bill ShanksAtlanta Dugout05/15/2016Braves fall to 8-26 with loss in KCThe Braves continue to have abysmal records as they lose the first game of the 10-game road trip.by Bill ShanksAtlanta Dugout05/13/2016Great night on the farm for the BravesThe failure of the major league team in Atlanta should not overshadow the great progress in the minor leagues.by Bill ShanksAtlanta Dugout05/10/2016The losses mount as Fredi stays onHere's the bad news.. by the numbers. The Braves continue to lose at an alarming rate.by Bill ShanksAtlanta Dugout05/10/2016Could Julio Teheran be traded?Will the new deal for Stephen Strasburg make it easier for the Braves to trade Julio Teheran?by Bill ShanksAtlanta Dugout05/10/2016Trending on ScoutSurprising players, positions at Vikings OTAsStronger Adams Focused on a Bounce-Back YearTeheran and Snitker react to Tuesday's lossZimmer praises Bridgewater’s progressRecruits Begin to React to Briles NewsWhy isn't Kelly Johnson playing more?Come on. Play Kelly Johnson. He's one of Atlanta's best players on the roster.by Bill ShanksAtlanta Dugout05/10/2016Touki Toussaint pitching well in RomeThe Braves really hope Touki Toussaint can become a top prospect. He's showing signs in Rome.by Bill ShanksAtlanta Dugout05/10/2016Braves meet with Mercer's Kyle LewisThe Braves may have interest in Mercer outfielder Kyle Lewis for the third overall pick.by Bill ShanksAtlanta Dugout05/10/2016Braves Talk - #FireFrediBill Shanks has plenty of thoughts about the Braves' current situation and the future of manager Fredi Gonzalez.by Bill ShanksAtlanta Dugout05/09/2016Braves getting benefits from tradesThe Braves got great returns in some of the blockbuster trades made in the rebuilding process.by Bill ShanksAtlanta Dugout05/08/2016ForumsThinking out loud here...by: BillShanks05/11/2016Braves Trade Rumorsby: FrankBrooks05/20/2016The losing continues... by the numbersWhen will the front office fire Fredi Gonzalez? What more do they need than these numbers?by Bill ShanksAtlanta Dugout05/08/2016Braves talk on 960 the Ref in AthensBill Shanks joined David Johnston and Sam Franco on 960 the Ref in Athens.by Bill ShanksAtlanta Dugout05/06/2016Braves should fire Fredi Gonzalez - nowThe Braves don't need to wait any longer. It's time for Fredi Gonzalez to go.by Bill ShanksAtlanta Dugout05/05/20161988 Braves vs. 2016 BravesLet's take a look at the 1988 Braves, a team that lost 106 games, against this year's Braves team.by Bill ShanksAtlanta Dugout05/04/2016Matt Wisler slows down the MetsHere's an update on the Braves, as Atlanta wins but the two farm teams have trouble on Tuesday.by Bill ShanksAtlanta Dugout05/04/2016Braves TalkBill Shanks talks about the Braves as they prepare for game two against the Mets in New Yorkby Bill ShanksAtlanta Dugout05/03/2016Braves' prospects shine in AprilHere is a look at how some of Atlanta's top prospects performed in the month of April.by Bill ShanksAtlanta Dugout05/01/2016Dansby Swanson InterviewBill Shanks talks with Dansby Swanson after his first game in Double-A, as his double and two-run home run allowed the Braves to win over the Jacksonville Suns.
by Bill ShanksAtlanta Dugout04/30/2016Kyle Tait InterviewBill Shanks visits with Mississippi announcer Kyle Tait on what's going on in Double-Aby Bill ShanksAtlanta Dugout04/30/2016Brandon Barker InterviewBill Shanks talks with former Mercer Bears starter Brandon Barker, now pitching for the Braves' Double-A affiliate in Mississippi.by Bill ShanksAtlanta Dugout04/30/2016Rob Whalen InterviewBill Shanks visits with Mississippi Braves pitching Rob Whalen, who was acquired from the Mets last summer.by Bill ShanksAtlanta Dugout04/30/2016Chris Ellis InterviewBill Shanks talks with Chris Ellis, one of the two pitching prospects acquired from the Angels in the Andrelton Simmons trade in November.by Bill ShanksAtlanta Dugout04/30/2016Dennis Lewallyn InterviewMississippi Braves pitching coach Dennis Lewallyn talks about Lucas Sims and his other pitching prospects.by Bill ShanksAtlanta Dugout04/30/2016Sean Newcomb InterviewBill Shanks chats with the Braves' top pitching prospect - Sean Newcomb.by Bill ShanksAtlanta Dugout04/30/2016Dave Trembley InterviewBill Shanks talks with Braves' farm director Dave Trembley about the promotions of Ozzie Albies and Dansby Swanson.by Bill ShanksAtlanta Dugout04/30/2016Braves promote Albies and SwansonThe Braves are challenging their top two prospects by sending Ozzie Albies to AAA Gwinnett and Dansby Swanson to AA Mississippi.by Bill ShanksAtlanta Dugout04/30/2016Dustin Peterson InterviewBill Shanks talks with Braves' prospect Dustin Peterson.by Bill ShanksAtlanta Dugout04/29/2016Ozzie Albies InterviewBill Shanks talks with Braves' top prospect Ozzie Albies. Can he make it to Atlanta this season?by Bill ShanksAtlanta Dugout04/29/2016The worst stretch in Atlanta's history?Bill Shanks has some frightening numbers on how bad the Braves have become.by Bill ShanksAtlanta Dugout04/28/2016How Bad is the Atlanta Braves Offense?We knew the Atlanta Braves offense was bad. We knew this offense was anemic, but these stats are mind numbing.by Scott KennedyAtlanta Dugout04/27/2016By the numbers - Just how bad is this?Here are the numbers to show just how bad the situation has become under the leadership of Fredi Gonzalez. This story will be updated daily.by Bill ShanksAtlanta Dugout04/27/2016Braves need to make a managerial changeBill Shanks has thoughts on the Braves, and there is only one solution to stop the bleeding.by Bill ShanksAtlanta Dugout04/27/2016Storylines: Dodgers set to call up UriasToday's piece focuses on the Dodgers calling up their top prospect, the Royals losing a key bat for the remainder of the year, Clay Buchholz potential move out of the rotation, and…by Andrew ZajacIndians Baseball InsiderYesterday at 10:28 PMBraves' Hector Olivera Suspended For 82 GamesAtlanta Braves' Hector Olivera suspended 82 games for domestic violence offense.by David BlumbergHardball ScoopYesterday at 2:51 PMThoughts on the minor leaguesBill Shanks has some news and notes on the Braves' minor league prospects.by Bill ShanksAtlanta Dugout04/23/2016Is Chipper Jones the Right Fit for Atlanta?Would the Atlanta Braves consider Chipper Jones as a serious managerial candidate?by David LevinHardball ScoopTuesday at 12:17 PMOrioles trade Brian Matusz, pick to BravesThe Baltimore Orioles sent Brian Matusz and a draft pick to the Atlanta Braves, as the Orioles received two prospects in the deal.by C.J. SmithHardball ScoopMonday at 6:20 PMRoyals, Phillies interested in Nick MarkakisNick Markakis could be the next veteran to be jettisoned out of Atlantaby David LevinHardball ScoopMonday at 7:58 AMBlue Jays make Drew Storen availableDrew Storen may be on the move again, as the Toronto Blue Jays have made him available on the trade market.by Mark SuleymanovHardball ScoopSunday at 8:44 PMBraves notesBill Shanks has some notes on the Atlanta Braves and the minor league system.by Bill ShanksAtlanta Dugout04/20/2016Braves Talk - Handling the bullpenBill Shanks talks about the issues with Fredi Gonzalez's bullpen management.by Bill ShanksAtlanta Dugout04/19/2016Kyle Tait InterviewBill Shanks talks with Mississippi Braves announcer Kyle Tait.by Bill ShanksAtlanta Dugout04/18/2016Did Fredi really use Wisler in relief?Bill Shanks talks about Braves' manager Fredi Gonzalez's decision to use starting pitcher Matt Wisler in relief.by Bill ShanksAtlanta Dugout04/18/2016Will Bud Black Manage the Atlanta Braves?The Atlanta Braves could name Bud Black as their new manager in 2017, as he is the "clear favorite."by David LevinHardball Scoop05/19/2016Braves Talk - Can the Braves avoid 0-10?Bill Shanks has thoughts on the Braves 0-9 start.by Bill ShanksAtlanta Dugout04/15/2016Is this the dumbest lineup ever?Bill Shanks has some thoughts on Friday's lineup.by Bill ShanksAtlanta Dugout04/15/2016Braves minor league starting pitchersCheck out what the starting pitchers in the minor leagues have done for the first week. The Braves are struggling at the big league level, but the prospects are off to a great…by Bill ShanksAtlanta Dugout04/15/2016Storylines: Braves can Fredi GonzalezThe Braves made the first managerial change of the 2016 season, the Indians called up a top pitching prospect, and more storylines from Tuesday evening.by Daniel SherriffIndians Baseball Insider05/17/2016Fredi Gonzalez's Firing was Way OverdueThe Atlanta Braves could not win with Fredi Gonzalez as manager of the ball club.by David LevinHardball Scoop05/17/2016Braves Talk - Olivera arrested in DCBill Shanks talks about the Braves' troubles in DC, including the arrest of the left fielder Hector Olivera.by Bill ShanksAtlanta Dugout04/13/2016Braves don't need to rush prospectsThe Braves' 2016 season is in trouble, but the organization does not need to rush its top prospects.by Bill ShanksAtlanta Dugout04/13/2016What's next for the Braves with Olivera gone?Bill Shanks looks at what's next for the Braves with Hector Olivera facing domestic abuse charges.by Bill ShanksAtlanta Dugout04/13/2016Braves TalkThe Braves continue to struggle. Bill Shanks has thoughts on the losing streak.by Bill ShanksAtlanta Dugout04/12/2016List of minor league plate appearancesBill Shanks has a list of how many plate appearance prominent Braves position players got in the minor leagues before their big league debuts.by Bill ShanksAtlanta Dugout04/12/2016Braves release Ryan LavarnwayRyan Lavarnway was released by the Atlanta Braves on Saturday.by David LevinHardball Scoop05/14/2016Braves Talk - Is Fredi to blame?Fans are not happy with the tough start. How much accountability falls at the feet of manager Fredi Gonzalez?by Bill ShanksAtlanta Dugout04/11/2016Will the Braves Finally Trade Julio Teheran?Will Julio Teheran be traded to a team needing a starter to complete a playoff run?by David LevinHardball Scoop05/14/20162016 MLB Mock Draft, Taylor Ward editionScout's Taylor Blake Ward throws out his predictions for the first 41 picks of the 2016 MLB Draft.by Taylor Blake WardScouting Baseball05/13/2016Patience will be required to watch this teamBill Shanks says this Braves team will test your patience, but the future remains bright.by Bill ShanksAtlanta Dugout04/10/2016Pitching again strong down on the farmPitching was the story once again on the farm as three top prospects did well.by Bill ShanksAtlanta Dugout04/10/2016Minor Leaguer of the Day - Chris EllisChris Ellis was tremendous in his first start in the Atlanta organization.by Bill ShanksAtlanta Dugout04/09/2016Braves ForumThinking out loud here...by: BillShanks956:31 AMAngels acquire Jhoulys Chacin from BravesThe Anaheim Angels have traded for Jhoulys Chacin to help its starting rotationby David LevinHardball Scoop05/11/2016Braves ForumBraves Trade Rumorsby: FrankBrooks848:39 AMBraves' prospects have a great first nightWhat a great night for the Atlanta prospects as the minor league season begins.by Bill ShanksAtlanta Dugout04/08/2016Load More

type: global

value: This website is an integrated sports publishing company that produces Internet content covering hundreds of professional and college teams across America. The company was founded in 2001 and was acquired by Fox Sports in 2005.


text:
Tascam Dr 08 Linear PCM MP3 Recorder Black | eBay Skip to main contenteBayShop bycategoryEnter your search keywordAll Categories Advanced or register':' style="margin-right:3px">Hi, #USER#!'.replace(/#USER#/,a))+"")}catch(b){document.write("")}})();Daily DealsSellCustomer SupportHi, (Sign in to bid or buy)My eBaySellCustomer SupportNotificationsCart Back to home page
Details about TASCAM DR-08 Linear PCM/MP3 Recorder Black
TASCAM DR-08 Linear PCM/MP3 Recorder Black
10:47:09 PDT
(258084
TASCAM DR-07mkII Ultra-Portable... $95.52
TEAC Tascam VR-20 Handheld Portable... $59.99
Very Nice Tascam DR-7 Digital Recorder $43.00
REFURBISHED! TASCAM DR-07mkII P... $119.99
Tascam Dr-07 MKII Linear PCM Recorder $124.99
Dean V Dave Mustaine United Abomination... $299.00
Takamine Pro Series 1 Jumbo Cutaway... $1,049.99
Audix ADX60 Boundary Microphone $219.00
Dean Custom 350F Electric Guitar Natural $349.00
Evans EMAD2 Clear Batter Head $31.77
eBay item number:200762047618
Click an Image to Enlarge TASCAM DR-08 Linear PCM/MP3 Recorder Black
item# 485395.001
The DR-08 is enough to fill your life with lovely recordings. Order today!
The compact TASCAM DR-08 Portable Digital Recorder packs serious audio quality into a handheld dynamo you can carry in your pocket. The DR-08 captures audiophile-quality 96kHz/24-bit WAV files Portador web-friendly MP3 filesto robust MicroSD media. The TASCAM DR-08 recorder's built-in microphones have a unique mechanism to change the width and angle of the elements, allowing you to tailor the pattern for the perfect recording. There's even a built-in kickstand for placing the DR-08 recorder right where you want it. A pair of AAA batteries enables you to record for hours to the included 2GB card, then transfer the recording to your computer using high-speed USB 2.0. Like TASCAM's other best-selling portable recorders, the DR-08 has features like auto level control and a low-cut filter for clear recordings. Add your own microphone or line-level source using the 1/8" stereo input. The DR-08 has loop and variable speed on playback, allowing you to slow down speed without changing the pitch to learn new music. There's also noise canceling and EQ functions for improved playback timbre. The TASCAM DR-08 is an ideal portable recorder for songwriters, live performers, business leaders, and even sound designers.Portable digital recorderWAV recording from 44.1/16-bit up to 96kHz/24-bitMP3 recording from 32k-320 KBpsRecords to MicroSD media (2GB card included)Two cardioid microphones with variable angle mechanism to adjust width and angle of microphone elementsVariable Speed Playback: adjust the playback speed from 50% to 200% without changing the pitch to learn new musicAuto recording mode starts recording when the input reaches a certain sound levelTimer recording mode for beginning recording at a certain time of dayManual and automatic gain control modesLow cut filter and noise cancel functions for clearer recording and playbackBuilt-in foldable stand for desktop recordingPre-recording buffer (up to 2 seconds)1/8" stereo mic/line input with plug-in power1/8" stereo headphone/line outputPlaylist and folder managementBuilt-in speakerTransfer recordings to computer using fast USB 2.0 connection (Micro-USB, B-type connector)96 x 96 backlit LCD display
Tascam Recorder,
Tascam DR-100,
Tascam DP-03 Recorder,
Tascam DR-1,

value: This website is an American multinational e-commerce corporation based in San Jose, California, that facilitates consumer-to-consumer and business-to-consumer sales through its website.


text:
Result Fsc Part 1 2013 | eBay Please enable JavaScript Our new search experience requires JavaScript to be enabled. Please enable JavaScript on your browser, then try again.
Skip to main contenteBayShop by categoryEnter your search keywordAll CategoriesAntiquesArtBabyBooksBusiness & IndustrialCameras & PhotoCell Phones & AccessoriesClothing, Shoes & AccessoriesCoins & Paper MoneyCollectiblesComputers/Tablets & NetworkingConsumer ElectronicsCraftsDolls & BearsDVDs & MovieseBay MotorsEntertainment MemorabiliaGift Cards & CouponsHealth & BeautyHome & GardenJewelry & WatchesMusicMusical Instruments & GearPet SuppliesPottery & GlassReal EstateSpecialty ServicesSporting GoodsSports Mem, Cards & Fan ShopStampsTickets & ExperiencesToys & HobbiesTravelVideo Games & ConsolesEverything ElseAdvanced or register':' style="margin-right:3px">Hi -User-!'.replace(/-User-/,escape(a)))+"")}catch(b){document.write("")}})();Hi (Sign in to bid or buy)Daily DealsGift CardsSellHelp & ContactMy eBayExpand My eBaySummaryBids/OffersWatch listWish listAll listsPurchase historySellingMy CollectionsFollowed searchesMessagesNotification Refine your search for Result Fsc Part 1 2013
0 results found for Result Fsc Part 1 2013
Result Fsc Part 1 2013: This is the median price based on sales of this product in the same condition from all listings on ebay.com in the past 14 days, or if there are any insufficient number of listings for a meaningful calculation, the past 90 days.
More items related to "Result Fsc Part 1 2013"
2013 Southern Shores FSC First Camporee Fall Camporee Fall Scene Orange CSP
Hinson FSC Clutch Fiber Spring Kit Steel For Honda CR125R CRF250R/250X KTM
Hinson Clutch Plate/Spring Kit For Kawasaki KFX/KLX/KX450R/F 2006-2013
Southern Shores Field Service Council set of 4 Different CSP's Mint
Hinson FSC Clutch Fiber Spring Kit Steel For Yamaha WR250F YZ250F 2001-2013 FSC1
Hinson FSC Clutch Plate Kit 6-Plates Fiber For Honda CRF150R/Expert
Dental Decks Part 1 2012-2013 Edition
Hinson Clutch Plate/Spring Kit For Suzuki RMX450Z RM-Z450 2005-2013
1.54K Ohm Precision Resistors 25 Pieces 1/8 watt Part number: 1541 FSC-1 337H
Apple Mac Pro Late 2013 Quad Core 32GB RAM 1TB Flash Storage Dual D300 Yosemite
Hinson FSC Clutch Fiber Spring Kit Steel For Yamaha WR250F YZ250F 2001-2013
WOLVERINE #8 1:50 YU VARIANT COVER KILLABLE part 1 2013 MARVEL X-MEN COMIC BOOK
Dental Decks NBDE Part 1 2013-2014 - COMPLETE - Used to PASS NBDE 1!
NISSAN DEALER-2013-2015-GENUINE OEM-PATHFINDER-CROSSBAR KIT-PART# 999R1-XZ500
Hinson Clutch Plate/Spring Kit For Honda CRF250R 2010-2013
Hinson FSC Clutch Fiber Spring Kit Steel For Yamaha YZ85 2002-2013
SDCC 2013 Justice League 22 Variant Trinity War Part 1 Fold Out Cover Exclusive
Hinson FSC Clutch Plate Kit 5-Plates Fiber For Honda CRF150R/Expert
CHARLIE BEARS 2013 PART 1 PLUSH MAGIC 16" BRAND NEW
Hinson FSC Clutch Plate Kit With Springs For Honda CRF150R FSC290-6-001
BEAUMARIS Charlie Bears Bearhouse Bears 2013 Plush PART 1
Infinity #2 Part Two (2013) CGC Graded 9.8 ~ Cheung Sketch Cover ~ 1:50 Ratio
Hinson FSC Clutch Plate Kit 7-Plates Fiber For Kawasaki KLX400R Suzuki DR-Z400


text:
Every Nonprofit's Guide to Publishing: Creating Newsletters, Magazines & Websites People Will Read by Cheryl Woodard | 9781413306583 | Paperback | Barnes & Noble
Every Nonprofit's Guide to Publishing: Creating Newsletters, Magazines & Websites People Will Read by
Overview Everything you need to raise awareness, membership and money! Nonprofits have certain advantages passion, motivation, a sense of purpose. But to raise the money and support required to achieve your goals you need to communicate your mission effectively. You can do it -- let Every Nonprofit's Guide to ...
Everything you need to raise awareness, membership and money!
Nonprofits have certain advantages passion, motivation, a sense of purpose. But to raise the money and support required to achieve your goals you need to communicate your mission effectively.
You can do it -- let Every Nonprofit's Guide to Publishing show you how!
Practical and hands on, this book shows you how to overcome inexperience and budget constraints -- and produce publications that effectively promote your cause. From developing an idea to distributing the final publication, you'll get the information you
need. Find out how to:
design and print engaging magazines or newsletters
locate the best freelancers and vendors
develop successful ad sales and fundraising strategies
meet IRS and postal requirements for nonprofits
use time-tested publishing ideas and resources
The book includes practical suggestions from veteran insiders, whose experiences range from tiny nonprofit startups to large, established organizations. The CD-ROM provides essential forms, checklists, schedules, worksheets, spreadsheets and more.
John Griffin"The authors understand what it's like to work with little money and too much to do. It is great for training others or for answering your own questions..."--(John Griffin, President Magazine Group, National Geographic)
Jay Harris"Offers invaluable advice for creating print and online publications that will grab an audience -- and stir them to action -- without overspending your budget."--(Jay Harris, President & Publisher Mother Jones magazine)
Holly Brady"A practical, example-filled resource from two publishing experts who've been there, done that. This kind of experience-based advice is priceless."--(Holly Brady, Director, Stanford Publishing Courses)
ForeWard MagazineDiscusses how organizations can overcome budget constraints and inexperience to produce products that will promote their cause...
Mother Jones magazineDo not lift a finger to start a nonprofit publishing venture before reading every page of this book.
— Mark Dowie
Mother JonesOffers invaluable advice for creating print and online publications that will grab an audience -- and stir them to action -- without overspending your budget.
National GeographicThe authors understand what it's like to work with little money and too much to do. It is great for training others or for answering your own questions...
Stanford Publishing CoursesA practical, example-filled resource from two publishing experts who've been there, done that. This kind of experience-based advice is priceless...
— Holly Brady
The Nonprofit QuarterlyThis comprehensive guide covers -- in an informative and lively way -- everything you'll need to manage your publication from concept to finished product.
— Timothy Lyster
ISBN-13: 9781413306583
Edition description: Book and CD-ROMEdition number: 1Pages: 464Sales rank: 637,098Product dimensions: 7.00 (w) x 9.00 (h) x 1.25 (d)
Cheryl Woodard learned the publishing business like most people do -- by jumping bravely into it without any preparation whatsoever. She co-founded PC, Macworld, PC World and Publish magazines, concentrating her attention on ad sales, circulation marketing and business management issues. In 1993, Cheryl began consulting with book, software, newsletter and magazine publishers. Author of Starting & Running a Successful Newsletter or Magazine, she specializes in helping business owners or chief executives sort out marketing and overall business strategies. Woodard teaches business planning at the Stanford Professional Publishing Course and other professional development programs. She also serves on the board of directors of the Independent Press Association in San Francisco. She lives with her husband and two children in Berkeley, California. Lucia Hwang is an award-winning investigative reporter and feature writer. Since 2004, she has worked as the editor for the magazine of a nonprofit association. Hwang has been a staff and freelance writer for a wide variety of publications -- ranging from daily newspapers to alternative weeklies to magazines -- and has also taught investigative reporting and news writing. She is a graduate of the University of California, Berkeley and the Columbia University Graduate School of Journalism.
Every publication serves two masters: the organization that pays the publishing bills and the people who read it. This chapter will help you create a publication that meets both of their needs.
First, it reviews the most common reasons nonprofit organizations launch newsletters, magazines, and online publications. Next, it discusses your publication's purpose, focusing entirely on how it will meet your organization's needs. It then explains how to meet your readers' needs through establishing the publication's editorial mission. It offers practical
advice about how to balance the interests of your nonprofit and the publication's readers -- and ends with some tips for troubleshooting common problems.
While it may seem easy to define a publication's purpose and mission, expect some disagreement -- especially if the publishing venture is new or represents a change from the way things have been done in the past. Publications often generate new and unexpected confusion within a nonprofit or churn up longstanding controversies within it.
Often, no one on staff has any editing or publishing experience, but everybody has ideas about what should be published in the new newsletter, magazine, or website. Some ideas will be wonderful. And some will be completely inappropriate -- such as the one from the board member who wants to put his grandson's video project on your alumni association website. Or the major donor who wants to advertise her Hummer dealership in your ecology club newsletter.
Money can be another source of confusion and dissension. Program managers may resent the money earmarked for a flashy website ratherthan for their programs, and board members may have unreasonable hopes about generating donations or ad revenues with a new magazine.
And, not knowing any better, everyone may expect to create a first-class product on a third-class budget, with no extra staff and no extra time allowed for planning sensibly.
You will never completely avoid conflict, but you can reduce much of it by taking the time to thoroughly discuss and define both a purpose and an editorial mission for every new magazine, newsletter, or online publication. (See "Crafting Your Mission Statement," below, for details about communicating ideas within the organization.) This step will help
manage everyone's expectations, and also help fend off inappropriate suggestions down the road, by developing and communicating your plans before the publishing begins. And if you are reevaluating an established publication -- looking for a new direction or greater impact -- then writing the purpose and mission statements anew can lead to fresh ideas and help resolve dissension. (See "Troubleshooting Editorial Mission Problems," below, for more about revamping a conflicted publishing project.)
The Publication's Purpose
The first essential task is to decide what purpose a publication will serve for its organizational master, your nonprofit, and how it will contribute to those goals. Think in terms of outcomes that you hope will result after making the effort to publish: more donations, happier volunteers, greater success in your efforts to educate or empower people. The road to successful publishing starts with a clear sense of where you want to go and why.
Often, the purpose of a nonprofit's publication is obvious and unequivocal: The board of directors wants to attract younger members by sending out an email newsletter, for example, or the organization's new director who has venture capital roots hopes to attract big donors through a slick magazine. But sometimes the purpose is less clear -- and in those situations, it is wise to gather input from a group of those involved to get a consensus before going forward. (See "Crafting Your Mission Statement," below, for details.)
There are a number of reasons nonprofit organizations typically decide to publish a magazine, newsletter, or website -- ranging from getting new members to targeting underserved ones. Often, a publication serves a number of purposes.
Publications can be extremely effective in recruiting and retaining members for consumer associations, arts organizations, and hobby or professional groups. Skimming through nonprofit member publications, you will usually find membership issues highlighted through photographs of
organization activities, articles promoting the benefits of belonging, and information about how to participate. In addition, by providing useful information about the nonprofit's cherished causes, such publications can become prized benefits on their own. In fact, organizations commonly list their print publications, electronic newsletters, and members-only Web features as primary membership benefits.
While the technique is not generally available for newsletters or not relevant for online publications, some nonprofits use their magazines to recruit members by distributing them widely on newsstands and in bookstores.
Example: The National Audubon Society produces a lavish, award-winning magazine, Audubon, to inspire new readers to join one of the 500 local chapters of the Society and help protect wildlife. Published bimonthly, the magazine is a public expression of the group's mission and activities. Every issue is filled with inspiring nature photographs, articles about how to participate in the Society's work around the world, and thoughtful information about environmental issues.
Not every member publication needs to be lavishly produced to attract the attention of potential members. It is most important for the publication to reflect the mission and voice of your organization.
Example: The magazine Coop America Quarterly has a humble, down-to-business appearance befitting the organization's mission, which is harnessing economic power to create a socially just and environmentally sustainable society. The publication's editors convey the value of belonging to the organization by packing each 40 practical advice on sustainable living and responsible investing. People looking for an alternative to the high-consumption values they find in other magazines are attracted to the low-impact values expressed in the Quarterly, and the magazine draws in lots of new members at "green living" conventions and other venues where it is displayed.
Some people are compelled to join a particular nonprofit organization because they crave a connection to people with whom they work or live. This is true for some unions and rural cooperatives that exist because of a shared type of work or location.
In addition to making new people feel welcome, these organizations can use their publications to remind existing members how they benefit from belonging to the organization and encourage them to remain involved.
Example: Kentucky Living is a monthly magazine that reaches 500,000 members of the state's rural electric cooperatives. It is distributed exclusively to people who already belong to a cooperative, and there is no attempt to use the magazine to recruit outside readers or new members. Instead, the magazine's sole purpose is to "create a community of people who take pride in thinking of themselves as Kentuckians and as knowledgeable electric coop members to improve their quality of life." The design is humble to deliberately send members a message that their money is not being used for lavish publication expenses -- and the content is helpful rather than confrontational. The editors steer clear of divisive politics, for example, and focus instead on profiles of local people and articles about energy efficiency. Ads are welcomed, particularly from local companies and coop members.
Educating About Issues
Many nonprofit publications are designed to "change the world" by arming individuals with information that empowers them to make thoughtful choices. The newsstands are filled with examples in the fields of environmental protection, health care, public affairs, culture, and social justice.
The goal of these publications is to reach as many like-minded people as possible and provide readers with unique and compelling information about the nonprofit's cause. To reach the widest possible audience, organizations with a cause to promote often decide to publish in several formats at once: websites, blogs, podcasts, electronic newsletters, and print publications. And every publishing effort is designed to reflect the mission and the expectations of the audience -- using environmentally friendly soy inks for an ecology magazine, for example, or online audio clips and blogs for one about political issues.
Example: Mother Jones magazine publishes revelatory journalism that seeks to "inform and inspire a more just and democratic world." Designed to reach the widest possible audience, the magazine is distributed in bookstores and to about 200,000 paid subscribers. Each bimonthly issue averages 90 pages in print with additional material simultaneously published online. The magazine is also available on microfilm, on CD-ROM, and electronically, and the organization also recently launched a radio program, podcasts, and blogs. When the editors take up an issue such as global warming or campaign finance reform, they are also able to engage readers in a two-way conversation through online forums.
But a big-scale approach to news may not be reasonable for every cause-related publication. Many smaller nonprofits choose to focus on communicating in depth with a smaller number of people -- a strategy that does not require many resources. Nonprofits can have tremendous impact by concentrating on a small, tightly defined audience and then providing wonderful journalism packaged in much humbler clothing.
Example: The Ecology Center of Berkeley, California, publishes Terrain magazine four times per year. Its mission is to educate and inform a dedicated community of environmental activists living in the San Francisco area -- people who have been working on environmental issues for many years. To save costs, each issue is limited to 40 pages produced on the least expensive paper, with minimal use of color and other expensive design elements. Instead of spending money on fancy packaging or technology, the Terrain editors focus the nonprofit's small budget on acquiring great reporting from a large stable of talented local writers.
Activating Readers
Having assembled an audience of like-minded people, many organizations use a publication to call them into action on specific issues. Through a newsletter, a magazine, a website, or emails, readers can be recruited to write letters, sign petitions, donate money, vote, volunteer, or attend conferences. The editorial style of these communications is focused and specific -- telling targeted individuals what they're being asked to do and why and providing an easy way to respond.
Example: By covering political and education issues in its main newsletter, California Teacher, the California Federation of Teachers tries to motivate its readership to advocate for the teaching profession, whether it's for more respect, better funding, or defeating political measures seen as damaging to students and teachers. The newsletter is one of the union's main methods for communicating with and activating its 120,000 members. For example, its articles explain why the organization endorses candidates and ballot measures. It has asked readers to donate money to causes to help teacher colleagues in other parts of the country. And it encourages readers to attend upcoming conferences and meetings of the organization's leadership by listing a calendar of events in every issue.
Lobbying restrictions. Some 501(c) nonprofits either cannot take any stances on political initiatives or offices or must severely limit their spending on political activities. Unions and some other organizations are given special leeway, but many nonprofits are legally restricted in lobbying. Be sure you know the rules for your organization before you start publishing. (See Chapter 5, "Lobbying Restrictions May Limit Your Content," for more details.)
Often, the best future contributors to an organization are the people who have made a donation in the past. Recognizing this, many nonprofits publish newsletters or magazines just for their donors and volunteers, or have sections or entire websites that only people fitting
these categories can access.
These publications focus on communicating the work the organization is doing for an important cause and highlight why that work is important. Sometimes citing academic experts, independent journalists, or government officials, these publications often take pains to educate readers about the overall state of the problem and the remedies their nonprofit is developing. Such publications are often filled with appeals for additional support and photographs of the people who benefit from it. It's also a common practice to profile and praise volunteers so that other people are inspired to do the same.
Example: World Ark magazine is a donor publication published by the Heifer Project, a group that strives to end world hunger through sustainable agriculture programs. Anyone who gives $25 to Heifer automatically receives a year's subscription to World Ark. Each issue profiles successful Heifer projects and explains the organization's different programs around the world. Photographs show the faces of people Heifer is helping and the Heifer volunteers who are helping them. The magazine puts Heifer's work in context by running excerpts from popular books, for example, or statistical information about poverty -- so that readers also learn something. The magazine has been so successful at raising new donations from past contributors that Heifer recently was able to increase its frequency from four to six issues per year and the number of pages in every issue from 36 to 48.
The Publication's Editorial Mission
Troubleshooting Editorial Mission Problems
2. Managing the Publishing Process
Creating Calendars and Schedules
Consulting With Accounting Advisers
Budgeting Tips for Publications
Using Budgets to Prove Performance
4. Finding and Hiring Help
Common Tasks and Staffing
Establishing an Editorial Advisory Board
What to Do When Short-Handed
Managing Freelance Arrangements
6. Designing Print Publications and Websites
Your Publication's Design
Creating a Design Grid
Tips for Saving Money on Design
7. Printing Newsletters and Magazines
A Look at the Mechanics of Printing
Getting Distribution Help From Printers
Troubleshooting the Printer Relationship
8. Producing a Website
Strengths of theWeb
9. Distributing and Promoting Your Publication
Pricing Your Publication
Choosing the Best Promotion Strategies
Tracking Readers Through a Database Program
Mailing Through the US Postal Service
10. Selling Advertising
Deciding Whether to Sell Ads
Managing the Ad Sales Process
Completing Your Advertising Plan
11. Connecting to Readers
Is Your Publication Fulfilling Its Purpose?
Creating Surveys and Other Feedback Tools
Using Feedback to Win Support
Hiring Artists, Writers, and Designers
Nonprofits, Generally
Publishing Courses and Seminars
Publishing, Generally

value: This website is an American bookseller. It is a Fortune 1000 company and the bookseller with the largest number of retail outlets in the United States.