Exploitation of channel division multiple access diversity in UWB MB-OFDM system

In this paper, we investigate a new waveform for UWB systems obtained by the combination of MBOFDM and an innovative scheme that exploits the user´s channels to guarantee multiple accesses called Channel Division Multiple Access (ChDMA). The proposed system, allows to use the CIR of each user as a signature .The new waveform is location-dependent property provides decentralized flexible multiple access as the codes are naturally generated by the radio channel. The analysis is focused on the improvement of the MB-OFDM system in terms of the spectral efficiency (bps/s/hz). The proposed structure is focused on the optimal receiver when synchronous ChDMA is employed to adapt the transceiver architecture with the purpose to maximize the system capacity and to ameliorate the spectral efficiency to be able to achieve high data rates. Our analyses is generalized to Nakagami fading channels in terms of probability distribution function(PDF) using tools from Random Matrix Theory where the performance of communication is determined by the eigenvalues of the covariance matrix.