Adaptive Equalization Super-Resolution Time Delay Estimation with High Accuracy and Low Complexity

An adaptive multipath equalization time delay estimation (METDE) algorithm is presented to estimate the time delays of received signals through a multipath channel with high accuracy and resolution. The proposed approach is developed utilizing a sequential minimization of a square error function that is updated according to the difference of received data and pre-known model at each moment. The METDE algorithm is uniquely established through a multi-tap equalizer structure and without using any complex optimization or matrix inversion operation. Thus, it will have lower complexity and better compatibility with practical hardware implementation in the real-time systems. The mathematical formulation and the accuracy analyses of the METDE algorithm are derived in the paper through numerical simulations and experimental tests. Providing 95% improved resolution compared to the Fourier limit, the proposed approach is a good candidate in low-frequency applications to mitigate the Fourier limit on the range resolution and achieve higher penetration in lossy environments.