CAJ | 학술논문

针对互模糊函数进行时频差联合估计时运算量大、受采样率和数据量限制，两者估计精度难以同时提高的问题，结合雷达信号的周期性和低轨双星中信号信噪比高、时频差范围有限等特点，提出了一种通过时域周期延拓计算相关函数主值区间，再利用脉内信号计算混合积信号频谱，最后由Chirp-Z变换完成时频域的高效插值，获取时频差精确估计的分步算法。仿真结果表明该算法在降低运算量同时，保证了估计精度。
침대호모호함수진행시빈차연합고계시운산량대、수채양솔화수거량한제，량자고계정도난이동시제고적문제，결합뢰체신호적주기성화저궤쌍성중신호신조비고、시빈차범위유한등특점，제출료일충통과시역주기연탁계산상관함수주치구간，재이용맥내신호계산혼합적신호빈보，최후유Chirp-Z변환완성시빈역적고효삽치，획취시빈차정학고계적분보산법。방진결과표명해산법재강저운산량동시，보증료고계정도。
Cross ambiguity function (CAF) in the joint estimation of time difference of arrival (TDOA) and frequency difference of arrival (FDOA) is limited by large computation load, sampling rate and data size. To solve these problems, a fast algorithm of TDOA and FDOA estimation based on the characteristics of radar signal in the situation of LEO dual-satellite passive location is proposed, which first estimates the TDOA by prolonging the signals periodically and only computes the main zone of the correlation function, then estimates the FDOA by Fourier transform of the mixed signal only with the internal signal of pulses, and finally interpolates in time domain and frequency domain effectively. The simulation results show that the proposed algorithm not only decreases the computation load but also guarantees the high estimation accuracy.