The Design Of FIR Digital Filter Based On DSP

This article tells us the characteristics and design methods of digital filter, It compared FIR with IIR digital filter and detailedly narrated the application area application foreground and development of digital filter. It particularly introduces the design method of FIR digital filter based on the software MATLAB and how to design digital filters with fdatool which is the filter designing tool of MATLAB.Choose the TMS320LF2407A as the processing chip to design the hardware circuit, on the basis of the designing point, design the peripheral circuit, such as clock signal circuit, power supply circuit, A/D conversion, D/A conversion, data amplifying circuit, SPI communication connection circuit and SPI registers configuration. Combining the peripheral circuit finish the system hardware circuit.In the software designing, using MATLAB/Simulink set up the model of data signal processing and going along the imitating. The figure file can be made into the C language program which is downed into the DSP aiming board. This program needed appending A/D and D/A meeting program, debugging and editing. It can design and realize many functions using these models and other digital signal processing models under the condition of Simulink. The program can be modified and edited in the development environment CCS. MATLAB accelerate developing period and be more convenient than CCS.This article give the hardware interface circuit designing and a C language program of digital bandstop filter, choosing the TMS320LF2407A and imitating the module of digital filtering processing in the MATLAB/Simulink. The program has already been applied in the hardware circuit. Many tests has proved that the program works stably and meets the designing needs. At the same time, the linear phase of FIR digital filter is proved, that is, the input and output wave has no distortion but time delay.