Impulsive noise suppression for robust iterative timing recovery in non-Gaussian channels

Abstract

Conventional iterative timing recovery is developed based on the widely used assumption of Additive White Gaussian noise (AWGN) interference. The Gaussian-based approach is excellent for timing recovery over AWGN channel with matched filtering approach but does not perform well in the presence of non-Gaussian noise. Overall performance of the conventional iterative timing recovery with matched filtering is significantly degraded in non-Gaussian channel. The root cause of the degradation is due to the received symbols are purged by the impulsive outliers from the non-Gaussian channels. Hence, this paper proposed a mitigation technique to address the issue for iterative timing recovery. In order to overcome this problem, a Matched Myriad filtering framework is proposed to be incorporated into iterative timing recovery as front-end receive filter. With the k tuning parameter of the robust Matched Myriad filter which caters for varying channel conditions, the iterative timing recovery can perform robustly and its performance is close to the benchmark of having its performance over the Gaussian channel. It is shown from simulations that more reliable received samples can be acquired to produce the accurate timing estimates and outputs.