A Comparative Study of Subspace-based Superresolution Path Delay Estimation Techniques

Accurate and high-resolution channel path delay estimation is essential for channel impulse response (CIR)-based localization algorithms. Since the conventional cross-correlation (CCR) or matched filter approach cannot provide reasonable performance, especially when fractional delays regarding the sampling interval exist, several superresolution path delay estimation (SPDE) algorithms are proposed to improve the accuracy and resolution. However, the performance of the established SPDE method is limited under low signal-to-noise ratio (SNR) conditions. In this paper, inspired by the direction of arrival (DoA) estimation algorithms, we present some methodologies to improve the estimation performance of SPDE and reveal the required modification to enable multi-band SPDE. In addition, a comparison among different methods is shown.