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Multi-Camer Code Division Multiple Access (MC-CDMA)is an attractive choice for high speed wireless communication as it mitigates the problem of Intersymbol Interference ( I S ) inherent in Code Division Multiple Access (CDMA) and also exploits frequency diversity unlike Orthogonal Frequency Division MultipIexing (OFDM). The data stream in MC-CDMA is spread using a user specific spreading sequence in the frequency domain and thus, every chip travels on a different sub-camer. At the receiver, the different subcarriers have to be combined properly to form the decision variable. Minimum Mean Square Error (MMSE) detector is a popular choice for this, but as it tries to minimize the Mean Square Error (MSE) and not the Bit Error Rate (BER), the BER it attains is not optimum. In this paper, we propose a Minimum Probability of Error (MPOE) based linear multiuser detector for uplink MC-CDMA, which tries to minimize the probability of error, by exploiting the probability density function (pdf) of the filter's output. Theoretical and simulation results are presented for the MPOE detector and it can be seen that the MPOE detector outperforms the MMSE detector in terms of BER and Near Far Resistance.

Minimum Variance Distortionless Response (MVDR) beam former is a spectral estimation technique where the power of signal in desired direction is maintained and the variance (power) in unwanted direction is minimized. MVDR beam former is generally used in adaptive arrays for adaptive nulling of jammerhterference. Genemlly in adaptive arrays QR decomposition is used for least square minimization of error, as it has less computational complexity and very fast convergence rate [I]. In this paper we propose, the application of genetic algorithm concepts for (GA) €or least square minimization in adaptive arrays. We show that the proposed algorithm is very efficient computationally compared to other algorithms available. The proposcd algorithm based only on binary operations.