Layered maximum likelihood detection for V-BLAST in frequency selective fading channels

This paper considers V-BLAST (vertically layered Bell Laboratories layered space-time) over a frequency selective fading channel environment. By considering the delayed elements in each transmit-receive antenna pair as imaginary antennas transmitting delayed versions of the substreams, we proposed a layered maximum likelihood detection (L-MLD) scheme in So and Cheng (2002). This scheme performs ordered ing, detection and cancellation to each substream and its delayed elements. However, it increases the required number of receiving antennas, thus increasing hardware cost and size. We propose the use of oversampling technique to increase the dimension of the received signal, hence reducing the minimum requirement on the number of receiving antennas. Simulation results show that the L-MLD scheme achieves frequency diversity and outperforms the V-BLAST system with OFDM. It also shows that further increasing the oversampling rate of L-MLD does not improve the performance.