An efficient space-frequency coded wideband OFDM system for wireless communications

A space-frequency coded OFDM system for high-speed transmission over wireless links is proposed. The analytical expression for the error event probability of such space-frequency coded OFDM system is derived in slow, spatial and frequency selective fading channels. The design criteria of TCM codes for the proposed system are then developed and discussed. It is shown that the proposed space-frequency coded OFDM with low trellis complexity can efficiently exploit the available diversity resources of the fading channel, while in conventional space-frequency coded OFDM systems, space-time trellis codes with very high trellis complexity are required to make full use of the diversity resources. Simulation results show that at a FER of 10/sup -2/, the proposed scheme outperforms the traditional space-frequency coded OFDM by 2-4 dB at an equal trellis complexity and spectral efficiency.

[1]  Leonard J. Cimini,et al.  Analysis and Simulation of a Digital Mobile Channel Using Orthogonal Frequency Division Multiplexing , 1985, IEEE Trans. Commun..

[2]  Xiaodong Wang,et al.  Space-time code design in OFDM systems , 2000, Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137).

[3]  G.B. Giannakis,et al.  Decoding and equalization of unknown multipath channels based on block precoding and transmit-antenna diversity , 1999, Conference Record of the Thirty-Third Asilomar Conference on Signals, Systems, and Computers (Cat. No.CH37020).

[4]  Tho Le-Ngoc,et al.  Coded-Modulation Techniques for Fading Channels , 1994 .

[5]  A. Robert Calderbank,et al.  Space-time block coding for wireless communications: performance results , 1999, IEEE J. Sel. Areas Commun..

[6]  Helmut Bölcskei,et al.  Space-frequency coded broadband OFDM systems , 2000, 2000 IEEE Wireless Communications and Networking Conference. Conference Record (Cat. No.00TH8540).

[7]  A. Robert Calderbank,et al.  Space-Time Codes for High Data Rate Wireless Communications : Performance criterion and Code Construction , 1998, IEEE Trans. Inf. Theory.

[8]  Vahid Tarokh,et al.  Space-time coded OFDM for high data-rate wireless communication over wideband channels , 1998, VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151).

[9]  Douglas B. Williams,et al.  A space-time coded transmitter diversity technique for frequency selective fading channels , 2000, Proceedings of the 2000 IEEE Sensor Array and Multichannel Signal Processing Workshop. SAM 2000 (Cat. No.00EX410).

[10]  Siavash M. Alamouti,et al.  A simple transmit diversity technique for wireless communications , 1998, IEEE J. Sel. Areas Commun..

[11]  Khaled Ben Letaief,et al.  Concatenated space-time block coding with trellis coded modulation in fading channels , 2002, IEEE Trans. Wirel. Commun..

[12]  Khaled Ben Letaief,et al.  Performance evaluation and analysis of space-time coding in unequalized multipath fading links , 2000, IEEE Trans. Commun..

[13]  Zhigang Cao,et al.  Analysis of low-complexity windowed DFT-based MMSE channel estimator for OFDM systems , 2001, IEEE Trans. Commun..

[14]  Khaled Ben Letaief,et al.  Space-frequency-time coded OFDM for broadband wireless communications , 2001, GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270).