A Low‐Complexity Target Detection Technique Using the Prefix Sum Algorithm

ABSTRACT A conventional target detection technique for FMCW millimeter‐wave radar applies a two‐dimensional (2D) cell‐averaging constant false alarm rate (CA‐CFAR) detector to all range‐doppler cells in order to suppress noise and clutter. However, this 2D CA‐CFAR method has significant drawbacks, particularly its high computational cost due to the large number of additions required, resulting in a time complexity of O(n 4 ). To decrease the computational complexity while ensuring the detection accuracy, a novelty CA‐CFAR technique based on the prefix sum algorithm with a complexity O(n 2 ) is proposed in this article. Simulations verify the feasibility of the proposed method. Compared to both conventional and state‐of‐the‐art optimized CA‐CFAR techniques, the proposed method reduces the number of addition operations by 95%, lowers CFAR loss by approximately 0.5 dB, and improves the figure of merit (FOM) by about 20% at a fixed false alarm rate of 10 −6 . This advanced technique offers significant computational efficiency for radar applications.