CN103647522A

CN103647522A - Four-mold remainder system based FIR filter and design method thereof

Info

Publication number: CN103647522A
Application number: CN201310577763.8A
Authority: CN
Inventors: 吕晓兰; 肖明
Original assignee: Individual
Current assignee: Guangdong University of Petrochemical Technology
Priority date: 2013-11-19
Filing date: 2013-11-19
Publication date: 2014-03-19

Abstract

The invention discloses a FIR filter based on a four-modulus remainder system and a design method thereof. The filter consists of a binary number to residual number conversion module, 4 FIR filter submodules and a residual number to binary number conversion module. It is made of modules; the design method of the FIR filter based on the four-modulus remainder system includes front-end design, hardware description language modeling, synthesis, and molding; the FIR filter based on the four-modulus remainder system of the present invention divides a calculation into several Independent of each other, independent of each other, the sub-computation of parallel operation eliminates the carry chain between each sub-calculation, and speeds up the calculation. In the selection of the module set, all the modules have the form of 2n and 2n±1. These special forms can be used to simplify the design of the hardware circuit of the converter, so that it can be realized with the simplest combinational logic circuit without occupying storage space.

Description

A kind of FIR filter and method for designing thereof based on four mould residue number systems

Technical field

The invention belongs to digital signal processing technique field, relate in particular to a kind of FIR filter and method for designing thereof based on four mould residue number systems.

Background technology

FIR filter circuit based on residue system utilizes remainder a calculating can be divided into several are independent of one another, be independent of each other, the son of parallel running calculates and word length remains constant essential advantage in whole computational process, effectively solved the problem that conventional filter exists, be more and more widely used in the filtering processing of Ultrahigh speed data stream.

In digital processing field, indispensable parts are finite impulse response filters.Its high stability has determined that it is widely used in the multiple fields such as communication, control, image and radar.Yet because FIR filter is a computing unit of taking advantage of crypto set type, therefore, under the impact of current ultrahigh speed information flow, the FIR filter of traditional binary number system has inevitably produced following problem:

1) guarantee real time communication.

2) precision and the effect of filtering by reducing the word length of tap number or adder and multiplier, have but been reduced.

Traditional solution is to adopt converter technique to realize, as fast Fourier transform (FFT) etc.Yet FFT is the mode deal with data with piece, thereby therefore in processing procedure, need a large amount of data bufferings to cause the time delay of output.

Adopting residue number system to build FIR filter is the effective ways that address the above problem.

Summary of the invention

The object of the present invention is to provide a kind of FIR filter and method for designing thereof based on four mould residue number systems, being intended to solve traditional Fourier transform is the mode deal with data with piece, thereby in processing procedure, needs a large amount of data bufferings to cause the problem of the time delay of output.

The present invention be achieved in that a kind of FIR filter based on four mould residue number systems by 1 binary number to remainder modular converter, 4 FIR filter submodules and 1 remainder to binary number modular converter form;

Further, the circuit of the described FIR filter based on four mould residue number systems, with 4 moulds combination { 2n-1,2n+1,22n, 22n+1-1}, can process 4 moulds simultaneously, the dynamic range of processing number reaches 6n+1 position, and whole circuit consists of combinational circuit completely, and each mould in set has the form of 2n and 2n ± 1 simultaneously;

A kind of method for designing of the FIR filter based on four mould residue number systems comprises Front-end Design, hardware description language modeling, comprehensive, moulding.Concrete steps are as follows:

Step 1, Front-end Design.

First, according to the parameter of filter, utilize the FDATool tool box of business software Matlab to design FIR filter.FDATool obtains the exponent number N of filter according to the filter parameter of input, the coefficient of filter, and then FDATool quantizes coefficient according to the quantified precision of designer's appointment.Designer determines the dynamic range M of residue number system according to the bit wide of the precision quantizing and input data, utilize formula

the value that determines mould set n, then solves quantization parameter about the remainder of each mould.

Step 2, hardware description language modeling.

Utilize Verilog or VHDL hardware description language to carry out remainder FIR modeling filter based on respective mode set, wherein, binary number is to the design of remainder transducer, the design of the mould adder of each passage, and mode multiplier is selected respectively the optimized design of previous stage.The parameter instantiation model of trying to achieve according to step 1, whether Bing Yong simulation software is as correct in ModelSim verifying logic.

Step 3, comprehensive.

The logically true instantiation remainder FIR filter that step 2 is obtained utilizes integrated software comprehensive, as Synopsys Design Compiler, obtain the minimum timing of critical path, then, the net table generating is done to rear imitating, the logical correctness of checking net table, errors excepted, should revise after logic, more imitative after comprehensive, this process circulation carries out until net table is correct.

Step 4, moulding.

Utilize net table, generate domain, the flow of contact chip Foundrymen.Also can be packaged into soft core or stone, with the form issue of IP kernel.

effect gathers

FIR filter based on four mould residue number systems of the present invention has following beneficial effect:

(1) FIR filter is the intensive Digital Signal Processing of multiply-add operation, and residue system has unrivaled pure concurrency on multiply-add operation, it is divided into a calculating, and several are independent of one another, be independent of each other, the son of concurrent operation calculates, eliminate the carry chain between each height calculates, accelerated the speed of calculating.

(2) based on residue system FIR filter, in mould set, choose, make to have mould all to there is the form of 2n and 2n ± 1 more.Can utilize these special forms to simplify the design of transducer hardware circuit, it be realized with the simplest combinational logic circuit completely, and needn't take memory space.

Accompanying drawing explanation

Fig. 1 is the overall architecture schematic diagram of the four-way FIR filter circuit based on residue system that provides of the embodiment of the present invention;

Fig. 2 is the design flow diagram of the four-way FIR filter circuit based on residue system that provides of the embodiment of the present invention;

Embodiment

In order to make object of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain the present invention, is not intended to limit the present invention.

As shown in Figure 1, a kind of FIR filter based on four mould residue number systems is by 1 binary number to remainder modular converter, and 4 FIR filter submodules and 1 remainder to binary number modular converter form;

As shown in Figure 2, a kind of method for designing of the FIR filter based on four mould residue number systems comprises

S101: Front-end Design;

S102: hardware description language modeling:;

S103: comprehensive;

S104: moulding.

Concrete steps are as follows:

Step 1, Front-end Design.

Step 2, hardware description language modeling.

Step 3, comprehensive.

Step 4, moulding.

Although above-mentioned, by reference to the accompanying drawings the specific embodiment of the present invention is described; but be not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various modifications that performing creative labour can make or distortion still within protection scope of the present invention.

Claims

1. a kind of FIR filter based on four modulus remainder system, it is characterized in that, described FIR filter based on four modulus remainder system is by 1 binary number to residual number conversion module, 4 FIR filter submodules and 1 It is composed of residual number to binary number conversion modules.

2. the FIR filter based on four modulus remainder system as claimed in claim 1, is characterized in that, the circuit of described FIR filter based on four modulus remainder system, combines {2n-1, 2n+1 with 4 mode , 22n, 22n+1-1}, can process 4 modules at the same time, the dynamic range of the processing number reaches 6n+1 bits, the whole circuit is completely composed of combinational circuits, and each module in the set has 2n and 2n±1 form.

3. A design method based on the FIR filter of the four-modulus remainder system, characterized in that, the described design method of the FIR filter based on the four-modulus remainder system comprises front-end design, hardware description language modeling, synthesis, molding.

4. the design method based on the FIR filter of four modulus remainder system as claimed in claim 3, is characterized in that, concrete steps are as follows:

Step 1. Front-end design;

First, according to the parameters of the filter, the FIR filter is designed using the FDATool toolbox of the commercial software Matlab. FDATool calculates the order N of the filter and the coefficients of the filter according to the input filter parameters, and then FDATool quantizes the coefficients according to the quantization precision specified by the designer; the designer determines the remainder system according to the quantization precision and the bit width of the input data The dynamic range M, using the formula

Determine the value of the modulus set n, and then solve the remainder of the quantization coefficient with respect to each modulus;

Step 2, hardware description language modeling;

Use Verilog or VHDL hardware description language to model the remainder FIR filter based on the corresponding modulus set. Among them, the design of the binary number to remainder converter, the design of the modulus adder of each channel, and the modulus multiplier are respectively selected from the last stage. Optimized design; instantiate the model according to the parameters obtained in step 1, and use simulation software such as ModelSim to verify whether the logic is correct;

Step three, synthesis;

The logically correct instantiated remainder FIR filter obtained in step 2 is synthesized by comprehensive software, such as Synopsys Design Compiler, to obtain the minimum timing of the critical path; then, post-simulate the generated netlist to verify the logical correctness of the netlist, If there is an error, the logic should be modified, then synthesized and imitated, and this process is executed cyclically until the netlist is correct;

Step four, forming;

Use the netlist to generate the layout and contact the chip foundry for tape-out; it can also be packaged into a soft core or hard core and released in the form of an IP core.