OFDM-CDM with V-BLAST detection and its extension to MIMO systems

In this paper, we propose the use of vertical Bell Labs layered space-time (V-BLAST) decision for orthogonal frequency division multiplexing code division multiplexing (OFDM-CDM) systems. Considering the properties of the V-BLAST detection as well as the frequency diversity from CDM, we propose a new CDM transform matrix to improve the performance of V-BLAST detection of OFDM-CDM signals. The V-BLAST detection of OFDM-CDM signals is also applied in multiple antenna systems. Simulation results show that we can achieve significant performance improvement using the V-BLAST detection scheme and the proposed CDM transform matrix for OFDM-CDM systems.