An Efficient Conflict-Free 2-D FFT for FMCW Radar Imaging on DSP

This article proposes an efficient 2D-FFT method based on the digital signal processing (DSP) platform, suitable for frequency-modulated continuous-wave (FMCW) radar systems. Given the real-time detection and imaging requirements of FMCW radar, enhancing system efficiency is of paramount importance. As a crucial step in fast algorithms for FMCW radar imaging, improving the calculation speed of 2D-FFT can significantly optimize system performance. As 2D-FFT is a data-intensive application with strided memory access patterns, traditional schemes cannot fully exploit the computing and storage performance of the DSP processor. Moreover, instruction and data parallelization often lead to memory access conflicts. This article introduces a multistage merged and conflict-free modulo addressing scheme called the CF2D-FFT algorithm, which reduces memory access operations and effectively resolves parallel memory conflicts. The proposed scheme is implemented and optimized on the HXDSP104x DSP platform, and the enhanced algorithm achieves a $1.24\times $ improvement over the theoretical runtime. The performance improvement of the proposed algorithm was validated through comparative experiments and imaging experiments.