Research The Algorithm Of Digital Filters And The Application In The DSP' System

Nowadays we are in the digital time, the technology of digital signal process is gotten extensive attention by people. Accompany with the development of technology of computer and microelectronics, the theory and arithmetic of digital signal process development quickly.Digital filter are used extensively in audio and video process, digital communications, frequency analysis , auto control and so on. Digital filter is one of the most important part of digital signal process , appeared in all digital signal process system almost.Digital filter is a discrete LIT system, can accomplish the signal filter using infinite precision arithmetic, with a group if one digital signal input( which sampled and measure with analog signal )and another group of changed digital signal output.In this paper, there are a lot of methods of designing digital filter. the current research situation, development trend and algorithm of digital filters had been researched and analyzed comprehensively in the industry at present , and so on . according to the project situation ,an algorithm of IIR digital filter based on the function of the ellipse is established. a digital filter hardware system in the core of the TMS320LF2407 of TI company is designed. The application of system program is produced automatically by MATLAB software designing and emulation. Main tasks as following:First, the basic theory of Algorithm, the methods of realization of IIR digital filters and the availability of the limited word length are introduced in detail. ellipse function closed with mechanism and design theory of IIR digital filter are analyzed in detail emphatic, which is based on the theory of designing digital filter.Then, the components which is a digital filter hardware based on DSP are introduced. according to the precision of digital signal processor and the work condition of system, the relevance to the types of the devices type such as DSP (TMS320LF2407) chip, ADC ,DAC and Memory etc are choosed and designed.At last, a lowpass digital filter with a function closed with ellipse is designed by making the use of the MATLAB software, the characteristic of the digital filter is analyzed. a mathematical model of the signal with the designed ellipse digital filter is established, filtered and emulated .In the DSP software designing course, the model of data signal processing is setted up in MATLAB/Simulink environment with the imitating. The designed imitating file .mdl can be made into the C language program directly, which is downed into the DSP aiming board and the DSP program is achieved automatic. because there is absence in some configurations in the running model process, there are a lot of questions during running the program.