Enhancement of small doppler frequencies detection for LFMCW radar.

Detection of targets with small Doppler frequencies of linear-frequency modulated continuous wave radars is the main task of this article. The moving target indicator (MTI) is used to reject the fixed targets and high-speed targets through the radar research area. In this work, targets with small Doppler frequencies can be detected perfectly based on the frequency response of a single delay line canceller followed by single delay line integrator. An enhancement of the proposed algorithm is achieved using a filter in the range direction of the range-Doppler processor scheme. The proposed filter is chosen with certain coefficients after the first fast Fourier transform processor in range to enhance the radar performance. The evaluation of the proposed algorithm is achieved at different slow Doppler scenarios of the target and compared with the traditional algorithm which uses only MTI processor. Another aspect that is important for evaluation of the proposed algorithm is the detection performance of the algorithms through the receiver operating characteristic curves. Implementation of the proposed algorithm using FPGA is performed in real time applications and it is found that it meets the simulation results.