High-throughput high-performance VBLAST-OFDM via carrier interferometry

摘要

Carrier interferometry (CI) may be used to spread OFDM symbols over all N subcarriers to exploit frequency diversity without loss in throughput. In this paper, we implement the OFDM (uncoded and coded) system incorporated with the carrier interferometry and VBLAST (Vertical Bell Laboratories layered Space-Time) to undertake performance comparison in frequency selective fading channel. It is shown that the novel systems, offer considerable high throughput provided by VBLAST architecture. The novel systems simultaneously achieve dramatic performance gains by taking advantage of large frequency diversity inherent in the CI/OFDM technique. The proposed VBLAST-CI/OFDM system outperforms the VBLAST-OFDM system by 5 dB at a BER of 10/sup -2/ and 8 dB at BER of 10/sup -3/. The VBLAST-CI/COFDM system demonstrates a 4 dB performance gain at a BER of 10/sup -3/ over the VBLAST-COFDM system. VBLAST-CI/COFDM system offers a performance 2dB better than COFDM at a BER of 10/sup -3/ and simultaneously provides a throughput P(the number of transmit antennas) times that of COFDM at the expense of receiver complexity.