Generalized BER of MCIK-OFDM with Imperfect CSI: Selection combining GD versus ML receivers

TL;DR

This paper develops a unified analytical framework for evaluating the BER of MCIK-OFDM systems with selection combining, comparing greedy and ML detectors under imperfect CSI, and offers insights into when simpler detectors suffice.

Contribution

It introduces a generalized BER analysis framework for MCIK-OFDM with selection combining, including closed-form expressions and asymptotic analysis under CSI imperfections.

Findings

Closed-form BER expressions for GD and ML detectors derived.

Asymptotic analysis reveals conditions favoring GD over ML.

Simulation results validate theoretical models and insights.

Abstract

This paper analyzes the bit error rate (BER) of multicarrier index keying - orthogonal frequency division multiplexing (MCIK-OFDM) with selection combining (SC) diversity reception. Particularly, we propose a generalized framework to derive the BER for both the low-complexity greedy detector (GD) and maximum likelihood (ML) detector. Based on this, closedform expressions for the BERs of MCIK-OFDM with the SC using either the ML or the GD are derived in presence of the channel state information (CSI) imperfection. The asymptotic analysis is presented to gain helpful insights into effects of different CSI conditions on the BERs of these two detectors. More importantly, we theoretically provide opportunities for using the GD instead of the ML under each specific CSI uncertainty, which depend on the number of receiver antennas and the M-ary modulation size. Finally, extensive simulation results are provided in order to validate our theoretical expressions and analysis.