A time spreaded quasi-orthogonal space-frequency coded scheme for OFDM systems

Author

Senthuran, Sivasothy ; Anpalagan, Alagan ; Das, Olivia

Author_Institution

Dept. of Electr. & Comput. Eng., Ryerson Univ., Toronto, ON

fYear

2008

fDate

24-26 June 2008

Firstpage

182

Lastpage

186

Abstract

A space-frequency (SF) coded orthogonal frequency division multiplexing (OFDM) system performs well in fast fading channels. The Hadamard time spreading offers additional time diversity gain with low complexity to SF-OFDM systems. Since quasi-orthogonal codes give higher data rate as compared to the orthogonal codes, this paper proposes a time spreaded quasi-orthogonal SF-OFDM system (called T-QOSF-OFDM) to achieve higher data rates with robust performance in fast fading channels. The proposed system performance is analyzed for different maximum Doppler frequency (f_d) and time block spreading factor (M) via Monte-Carlo simulation. The T-QOSF-OFDM with 4 transmitter and 1 receiver antenna configuration offers 2 dB gain over orthogonal SF-OFDM system for f_d = 300 Hz and M = 64 at BER of 10^-4.

Keywords

OFDM modulation; diversity reception; error statistics; fading channels; orthogonal codes; BER; Doppler frequency; Hadamard time spreading; Monte-Carlo simulation; SF-OFDM systems; T-QOSF-OFDM; fast fading channels; frequency 300 Hz; gain 2 dB; space-frequency coded orthogonal frequency division multiplexing system; time block spreading factor; time diversity gain; time spreaded quasiorthogonal space-frequency coded scheme; Diversity methods; Fading; Gain; OFDM; Performance analysis; Receiving antennas; Robustness; System performance; Transmitters; Transmitting antennas;

fLanguage

English

Publisher

ieee

Conference_Titel

Communications, 2008 24th Biennial Symposium on

Conference_Location

Kingston, ON

Print_ISBN

978-1-4244-1945-6

Electronic_ISBN

978-1-4244-1946-3

Type

conf

DOI

10.1109/BSC.2008.4563234

Filename

4563234