Performance analysis of joint time delay and Doppler-stretch estimation with random stepped-frequency signals

Abstract

Abstract-This paper investigates the performance of joint time delay and Doppler-stretch estimation with the random steppedfrequency (RSF) signal. Applying the ambiguity function (AF) to implement the estimation, we derive the compact expressions of the theoretical mean square errors (MSEs) under high signal-tonoise ratios (SNRs). The obtained MSEs are shown consistent with the corresponding Cramer-Rao lower bounds (CRLBs), implying that the AF-based estimation is approximately efficient. Waveform parameters including higher carrier frequencies, wider bandwidth covered by the carrier frequencies, and frequency shifting codewords with larger variance are expected for a better estimation performance. As a synthetic wideband signal, the RSF signal achieves the same estimation performance as the OFDM signal within an identical bandwidth. Due to its instantaneous narrowband character, requirement for the bandwidth of the receiver is much reduced.

Performance Bound for Joint Multiple Parameter Target Estimation in Sparse Stepped-Frequency Radar: A Comparison Analysis

“…In [8], the CRLB expression is derived to guide TDOA estimation using a frequency-hopping signal. Similarly, in [9,10], the performance of joint TD estimation is studied with random stepped frequency signals. In addition, some researchers have explored the performances of other parameters; e.g., in [11,12], the CRLB of a target’s position, intensity, and geometry type are derived by considering the signal as a geometric theory of diffraction (GTD)-based scattering center model.…”