Abstract: The capacity of code division multiple access ( CDMA) systems is limited by inter-symbol interference, multiple-access interference and nearfar effect as well. Joint detection ( JD) technology is introduced into CDM A systems to combat them. However, the interference and the nearfar effect cannot be eliminated completely with low complexity suboptimum joint detection technologies; therefore, we investigate the combination of JD and closed loop power control ( CLPC) algorithms. A blind adaptive CLPC algorithm is provided furthermore, to reduce block error rate of CDM A systems and the standard deviation of power control error.

Key words: code division multiple access, joint detection, power control