CAJ | 학술논문

根据线性调频连续波（LFMCW）信号的周期特点，提出累积 Wigner-Hough 变换（CWHT）进行 LFMCW 信号的参数估计。首先分析了自相关函数的特点，通过搜索自相关函数的峰值，实现了信号调制周期的估计。然后根据调制周期将信号分段，进行 CWHT。通过 CWHT 峰值和起始时间的搜索，最终估计出信号的调频斜率与起始频率。理论推导了 CWHT 的信噪比（SNR）公式，并分析了相关计算。该算法不仅减小了时频交叉项的影响，而且降低了计算的复杂度。同时由于进行了多个周期的非相干累积，提高了该算法的抗噪性能。仿真结果验证了本文算法在低 SNR 下具有较好的参数估计性能。
근거선성조빈련속파（LFMCW）신호적주기특점，제출루적 Wigner-Hough 변환（CWHT）진행 LFMCW 신호적삼수고계。수선분석료자상관함수적특점，통과수색자상관함수적봉치，실현료신호조제주기적고계。연후근거조제주기장신호분단，진행 CWHT。통과 CWHT 봉치화기시시간적수색，최종고계출신호적조빈사솔여기시빈솔。이론추도료 CWHT 적신조비（SNR）공식，병분석료상관계산。해산법불부감소료시빈교차항적영향，이차강저료계산적복잡도。동시유우진행료다개주기적비상간루적，제고료해산법적항조성능。방진결과험증료본문산법재저 SNR 하구유교호적삼수고계성능。
Cumulative Wigner-Hough Transform (CWHT)is proposed for parameter estimation of Linear Frequency Modulation Continuous Wave (LFMCW)signal according to the periodic characteristic of LFMCW signal.Firstly,the characteristic of autocorrelation function is analyzed and the modulated period of LFMCW signal is estimated by searching the peaks of autocorrelation function.Then,the LFMCW signal is segmented in several parts based on the modulated period in order to have CWHT.By searching the peak of CWHT and beginning time,the chirp rate and initial frequency of LFM-CW signal are estimated eventually.The Signal-to-Noise Ratio (SNR)formula of CWHT is derived theoretically and related calculations about CWHT are analyzed.Not only does the proposed algorithm reduce the impact of time-frequency cross term,but also has low computational complexity.At the same time,the algorithm can get noncoherent integration in several periods,that improves the ability of immunity to noise.The results of simulation verify that the proposed algorithm has a good performance of parameter estimation at a low SNR.