Low PAPR preamble-based channel estimation for OTFS systems on static multipath channels

Abstract

In this paper we propose two preamble-based channel estimation methods for orthogonal time frequency space (OTFS) modulation. These new methods allow a robust channel estimation in noisy scenarios and static multipath channels. Moreover, the proposed preambles exhibit a strong resilience to nonlinearities introduced by high power amplifiers (HPA). We demonstrate that our proposed methods outperform the existing techniques in the literature, allowing the HPA to work at a low input backoff (IBO). To the best of the authors' knowledge, this is the first paper that addresses a study of HPA linearity in OTFS systems. Finally, we show that the complexity of our channel estimators is low enough for an efficient hardware implementation.