Enhanced zero crossing frequency estimation for FMCW radar systems

This paper presents a spectral peak estimation technique for tight resources systems. Based on a basic zero-crossing (ZC) frequency estimator, an enhanced ZC frequency estimation technique is proposed. The technique conducts a tunable band-pass filter (BPF) that relies on a primary estimation from another ZC block. In principle, the filter reduces the noise content of the signal, hence increasing the quality of the ZC algorithm. The technique is computationally very efficient and can be easily implemented on low cost systems. It was evaluated in a practical frequency modulated continuous wave (FMCW) ranging system. A ranging precision of around 2.24 cm was practically achieved.