EXIT Chart Aided Convergence Analysis of Recursive Soft <inline-formula> <tex-math notation="LaTeX">$m$</tex-math> </inline-formula>-Sequence Initial Acquisition in Nakagami-m Fading Channels

Abstract

A delay of less than one millisecond is required by low-latency 5G wireless communication systems for supporting the “tactile” Internet. Hence, conventional initial synchronisation cannot be readily employed because of its potentially excessive delay. In this paper, an extrinsic information transfer (EXIT) chart assisted approach is used for the convergence analysis of $m$ -sequences using recursive soft sequence estimation (RSSE) in the context of Nakagami-m fading channels. Explicitly, the novelty of our work is based on employing a new type of EXIT charts operating without using interleavers. This is a challenge, because the original EXIT charts rely on the employment of long, high-delay interleavers for ensuring that the inputs to the decoders become uncorrelated. We then evaluate the performance of various classes of $m$ -sequences with the aid of the proposed EXIT charts and demonstrate that the $m$ -sequences generated by the lower order polynomials maximize the mutual information more promptly with the aid of our RSSE scheme than those that belong to a higher order polynomial.