High-resolution independent component analysis based time-of-arrival estimation for line-of-sight multipath environments

A novel super resolution time-of-arrival (TOA) estimation technique applicable to multipath wireless channels is proposed. Here, it is assumed that the line-of-sight signal is available. This technique applies the concept of independent component analysis (ICA) to the received signal in the frequency domain. The proposed ICA algorithm solves an optimisation problem for TOA estimation. The selection of a proper cost function for this optimisation is investigated. The objective is to improve the estimation performance in multipath environments. The proposed technique extracts the TOA estimation iteratively. An optimum initialisation constraint is incorporated to detect the desired (shortest) TOA as the first estimated time delay. This reduces the complexity of the proposed approach. Compared with the traditional super-resolution techniques such as MUSIC, this algorithm represents a lower sensitivity to signal-to-noise ratio (SNR) for positive SNRs, and bandwidth. The proposed method is a good candidate for high-resolution TOA estimation in rich scattering wireless environments. It possesses a low complexity implementation over many high-speed fixed-point platforms such as digital signal processor (DSP) and field programmable gate array (FPGA). The proposed technique has applications in radar, sonar, wireless local positioning systems, and, localisation in mobile ad hoc networks.