Timing Recovery and Sequence Detection for Integrate-and-Fire Time Encoding Receivers

TL;DR

This paper introduces a joint timing recovery and sequence detection method for neuromorphic time encoding receivers, improving synchronization and error rates in event-driven communication systems.

Contribution

It develops a maximum likelihood framework and a practical two-stage receiver for joint timing and data detection in integrate-and-fire time encoding receivers.

Findings

Accurate estimation of symbol timing offset achieved.

Enhanced symbol error rate performance demonstrated.

Effective joint detection method outperforms existing approaches.

Abstract

Recent advances in neuromorphic signal processing have introduced time encoding machines as a promising alternative to conventional uniform sampling for low-power communication receivers. In this paradigm, analog signals are converted into event timings by an integrate-and-fire circuit, allowing information to be represented through spike times rather than amplitude samples. While event-driven sampling eliminates the need for a fixed-rate clock, receivers equipped with integrate-and-fire time encoding machines, called time encoding receivers, often assume perfect symbol synchronization, leaving the problem of symbol timing recovery unresolved. This paper presents a joint timing recovery and data detection framework for integrate-and-fire time encoding receivers. The log-likelihood function is derived to capture the dependence between firing times, symbol timing offset, and transmitted sequence, leading to a maximum likelihood formulation for joint timing estimation and sequence detection. A practical two-stage receiver is developed, consisting of a timing recovery algorithm followed by a zero-forcing detector. Simulation results demonstrate accurate symbol timing offset estimation and improved symbol error rate performance compared to existing time encoding receivers.