Set Partition Modulation

TL;DR

This paper introduces set partition modulation (SPM), a new modulation scheme for OFDM that improves error performance and achievable rate by using set partitioning and graph theory-based codebook selection.

Contribution

The paper proposes SPM as a novel modulation scheme, develops a practical OFDM implementation, and introduces an efficient codebook selection algorithm with theoretical analysis.

Findings

SPM generalizes existing OFDM with index modulation schemes.

OFDM-SPM outperforms conventional OFDM and related IM schemes in error and rate.

The proposed codebook selection algorithm is fast and effective.

Abstract

In this paper, a novel modulation scheme called set partition modulation (SPM) is proposed. In this scheme, set partitioning and ordered subsets in the set partitions are used to form codewords. We define different SPM variants and depict a practical model for using SPM with orthogonal frequency division multiplexing (OFDM). For the OFDM-SPM schemes, different constellations are used to distinguish between different subsets in a set partition. To achieve good distance properties as well as better error performance for the OFDM-SPM codewords, we define a codebook selection problem and formulate such a problem as a clique problem in graph theory. In this regard, we propose a fast and efficient codebook selection algorithm. We analyze error and achievable rate performance of the proposed schemes and provide asymptotic results for the performance. It is shown that the proposed SPM variants are general schemes, which encompass multi-mode OFDM with index modulation (MM-OFDM-IM) and dual-mode OFDM with index modulation (DM-OFDM-IM) as special cases. It is also shown that OFDM-SPM schemes are capable of exhibiting better error performance and improved achievable rate than conventional OFDM, OFDM-IM, DM-OFDM-IM, and MM-OFDM-IM.