Parameter estimation of narrowband radio frequency interference based on local refinement search in frequency domain

Intensive narrowband radio frequency interference is a problem that very high frequency (VHF)/ultra-high frequency (UHF) radar must solve in the work. This paper proposes a sine wave parameter estimation method of local refinement search in frequency domain. It can estimate the frequency of narrowband radio frequency interference(RFI) by using fast Fourier transform(FFT) and chirp transform algorithm (CTA). Simulation shows that this method can estimate the phase of narrowband radio frequency interference accurately under the condition of low signal-to-noise ratio (SNR), and the estimating efficiency is much higher than classical algorithms.