With the continuous development of digital signal processing technology and the continuous expansion of its application fields, the requirements for filter performance and efficiency in scientific research and industrial practice are also rising. This paper argues that FIR filter can meet the design indexes and requirements of different fields in various application scenarios after improving the design method and algorithm. The key tap parameters of the filter are given by the powerful computing power of the mathematical calculation platform Matlab. In this paper, the simulation and verification of the filter design details and the final simulation results are demonstrated by the professional simulation platform ModelSim. In addition, the simulation results include the original signal and the filtered signal for easy comparison and thus can highlight the advantages of the filter designed in this paper. It can be clearly seen from the results presented in this paper that the clutter in the original signal is filtered within a reasonable processing time range, and the filtered output signal is almost the same as the theoretically filtered image, which indicates that the optimized FIR filter in this paper has excellent effect. Finally, because in the field of communication systems, image processing, and other fields where the current development momentum is steadily improving, it is often necessary to deal with the clutter introduced in this paper, the improved fir filter in this paper has considerable practical value in these fields and is worthy of in-depth study.