Deterministic pilot sequences for sparse channel estimation in OFDM systems

Abstract

This paper examines the problem of multipath channel estimation in single-antenna orthogonal frequency division multiplexing (OFDM) systems. In particular, we study the problem of pilot assisted channel estimation in wideband OFDM systems, where the time-domain (discrete) channel is approximately sparse. Existing works on this topic established that techniques from the compressed sensing literature can yield accurate channel estimates using a relatively small number of pilot tones, provided the pilots are selected randomly. Here, we describe a general purpose procedure for deterministic selection of pilot tones to be used for channel estimation, and establish guarantees for channel estimation accuracy using these sequences along with recovery techniques from the compressed sensing literature. Simulation results are presented to demonstrate the effectiveness of the proposed procedure in practice.