Low-Complexity ML Detector and Performance Analysis for OFDM With In-Phase/Quadrature Index Modulation

A novel variant of orthogonal frequency division multiplexing (OFDM) techniques, which carries additional information bits through the index domain including in-phase and quadrature dimensions, is recently proposed. For its nature, we refer to this technique as OFDM with in-phase/quadrature index modulation (OFDM-I/Q-IM). In this letter, we propose a novel low-complexity detector based on the maximum-likelihood (ML) criterion for OFDM-I/Q-IM, which does not need to know the variance of the noise and the possible realizations of the active subcarrier indices. With the proposed ML detector, the asymptotic average bit error probability (ABEP) and the exact coding gain achieved by OFDM-I/Q-IM are also derived.