Radar Sensing with OTFS: Embracing ISI and ICI to Surpass the Ambiguity Barrier

TL;DR

This paper introduces a novel OTFS radar signal model that leverages ISI and ICI effects to surpass traditional ambiguity limits, enhancing detection and estimation in high-mobility scenarios.

Contribution

It develops a new OTFS radar model incorporating ISI and ICI, and proposes a detector that exploits these effects to improve radar performance beyond existing limits.

Findings

ISI and ICI can be exploited to extend unambiguous detection range and velocity.

The proposed detector outperforms conventional methods in simulations.

Embracing interference effects leads to superior radar sensing capabilities.

Abstract

Orthogonal time frequency space (OTFS) is a promising alternative to orthogonal frequency division multiplexing (OFDM) in high-mobility beyond 5G communications. In this paper, we consider the problem of radar sensing with OTFS joint radar-communications waveform and derive a novel OTFS radar signal model by explicitly taking into account the intersymbol interference (ISI) and inter-carrier interference (ICI) effects. On the basis of the new model, we show how ISI and ICI phenomena can be turned into an advantage to surpass the maximum unambiguous detection limits in range and velocity, arising in existing OFDM and OTFS radar systems. Moreover, we design a generalized likelihood ratio test based detector/estimator that can embrace ISI and ICI effects. Simulation results illustrate the potential of embracing ISI/ICI and demonstrate its superior detection and estimation performance over conventional baselines.