Power Control for Mc-Cdma System with Predicted Csi Using Water Filling Algorithm

Multi-carrier CDMA technology is a very attractive multiple access technique for next generation wireless communication systems. It combines the advantages of both Orthogonal Frequency Division Multiplexing (OFDM) and Code Division Multiple Access (CDMA) for high data rate transmission. However, interference noise is considered as a major challenge for MC-CDMA systems and significantly affects its performance. The transmission strategy to avoid the interference noise is by its power allocation to each user. The Game theory is an efficient way for examining power control problem in the MC-CDMA technology. The water filling algorithm in game theory perspective is used to allocate proper power for every sub-channel based on channel state information (CSI) with global power constraint in order to improve the capacity of the MCCDMA system. The water filling provides optimal solution if the channel state information is perfect. In realistic high mobility environment, where the Doppler frequency is high, channel state information received at the transmitter is outdated due to CSI feedback delay which results in imperfectness in the channel state information. The capacity achieved using water filling game theory is analysed with Perfect CSI, Imperfect CSI and Predicted CSI. The water filling game theory with Predicted CSI shows improvement in the capacity compared to water filling game theory with Imperfect CSI.