Diversity Analysis of Bit-Interleaved Coded Multiple Beamforming with Orthogonal Frequency Division Multiplexing

TL;DR

This paper analyzes the diversity performance of BICMB-OFDM in broadband MIMO systems, deriving maximum diversity, conditions for full diversity, and proposing subcarrier grouping to mitigate correlation effects.

Contribution

It provides a theoretical diversity analysis of BICMB-OFDM, including maximum diversity derivation and correlation mitigation techniques.

Findings

Maximum achievable diversity derived

Full diversity condition RcSL <= 1 proved

Subcarrier grouping improves performance

Abstract

For broadband wireless communication systems, Orthogonal Frequency Division Multiplexing (OFDM) has been combined with Multi-Input Multi-Output (MIMO) techniques. Bit-Interleaved Coded Multiple Beamforming (BICMB) can achieve both spatial diversity and spatial multiplexing for flat fading MIMO channels. For frequency selective fading MIMO channels, BICMB with OFDM (BICMB-OFDM) can be applied to achieve both spatial diversity and multipath diversity, making it an important technique. However, analyzing the diversity of BICMB-OFDM is a challenging problem. In this paper, the diversity analysis of BICMB-OFDM is carried out. First, the maximum achievable diversity is derived and a full diversity condition RcSL <= 1 is proved, where Rc, S, and L are the code rate, the number of parallel steams transmitted at each subcarrier, and the number of channel taps, respectively. Then, the performance degradation due to the correlation among subcarriers is investigated. Finally, the subcarrier grouping technique is employed to combat the performance degradation and provide multi-user compatibility.