Research Article
A Combined MMSE-ML Detection for a Spectrally Efficient non Orthogonal FDM Signal
@INPROCEEDINGS{10.1109/BROADNETS.2008.4769119, author={Ioannis Kanaras and Arsenia Chorti and M.R.D. Rodrigues and Izzat Darwazeh}, title={A Combined MMSE-ML Detection for a Spectrally Efficient non Orthogonal FDM Signal}, proceedings={5th International ICST Conference on Broadband Communications, Networks, and Systems}, publisher={IEEE}, proceedings_a={BROADNETS}, year={2010}, month={5}, keywords={FDM MMSE ML Gram Schmidt}, doi={10.1109/BROADNETS.2008.4769119} }- Ioannis Kanaras
Arsenia Chorti
M.R.D. Rodrigues
Izzat Darwazeh
Year: 2010
A Combined MMSE-ML Detection for a Spectrally Efficient non Orthogonal FDM Signal
BROADNETS
IEEE
DOI: 10.1109/BROADNETS.2008.4769119
Abstract
In this paper, we investigate the possibility of reliable and computationally efficient detection for spectrally efficient non-orthogonal Multiplexing (FDM) system, exhibiting varying levels of intercarrier interference. Optimum detection is based on the Maximum Likelihood (ML) principle. However, ML is impractical due to its computational complexity. On the other hand, linear detection techniques such as Zero Forcing (ZF) and Minimum Mean Square Error (MMSE) exhibit poor performance. Consequently, we explore the combination of MMSE estimation with ML estimation around a neighborhood of the MMSE estimate. We evaluate the performance of the different schemes in Additive White Gaussian Noise (AWGN), with reference to the number of FDM carriers and their frequency separation. The combined MMSE-ML scheme achieves a near optimum error performance with polynomial complexity for a small number of BPSK FDM carriers. For QPSK modulation the performance of the proposed system improves for a large number of ML comparisons. In all cases, the detectability of the FDM signal is bounded by the signal dimension and the carriers frequency distance.