A Robust STBC-Based Transmit Diversity Scheme for OFDM Systems Over Spatially Transmit Correlated Fading Channels

• Published in: IEEE transactions on vehicular technology Vol. 56; no. 2; pp. 984 - 991
• Main Authors: KO, Eunseok, HONG, Daesik
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.03.2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Blocking; Channels; Coding, codes; Correlation analysis; Decoders; Decoding; Degradation; Diversity methods; Exact sciences and technology; Fading; Fourth-order diversity gain; Frequency diversity; Frequency division multiplexing; Humans; Information, signal and communications theory; Multiplexing; OFDM; Orthogonal Frequency Division Multiplexing; Robustness; Signal and communications theory; space-time block coded orthogonal frequency-division multiplexing (STBC-OFDM); spatial transmit correlation; Subcarriers; Systems, networks and services of telecommunications; Technology planning; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Fading channels; Performance evaluation; Block code; Space-time codes; space-time block coded orthogonal frequency-division multiplexing (STBC-OFDM); Spatial correlation; Correlation matrix; Space diversity; Mapping; Decoding; Subcarrier; spatial transmit correlation; Diversity combining; Algorithm complexity; Orthogonal frequency division multiplexing; Frequency diversity; Robustness; Fourth-order diversity gain
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2007.891414

In this paper, we propose a robust space-time block coded (STBC)-based transmit diversity scheme with low decoding complexity against spatially transmit-correlated fading channels compared with the conventional STBC orthogonal frequency-division multiplexing (STBC-OFDM) schemes. The proposed scheme is comprised of Alamouti code for spatial diversity and a simple mapping process with subcarrier selection for frequency diversity. Proceeding from a detailed analysis of the rank and determinant of the channel correlation matrix, we present a proper subcarrier selection scheme satisfying the conditions for robustness against spatial transmit correlation. Furthermore, when the receiver employs a low-complexity decoder such as a zero-forcing decoder, the proposed scheme shows improved performance compared with the existing space-frequency coded OFDM schemes