A study on blind adaptive receiver for DS-CDMA systems

The multiple access causes an interference problem in the direct-sequence c ode-division multiple process systems. An efficient adaptive algorithm shou ld be used to suppress this interference for the improvement of system perf ormance. In this: paper, the new blind adaptive method is suggested using t he constant modulus algorithm for the purpose of interference suppression. Simulation results show that the converged value of signal to interference ratio for the proposed method is approximately 6 [dB] larger than that of a conventional Blind-MOE receiver in the additive white Gaussian noise chann el and channel with inter-symbol interference while the signal. to interfer ence ratio improvement is almost 4 [dB] better in the Rayleigh Fading chann el. The suggested method is also robust to the new user interference result ing the nearly 3 [dB] improvement of the SIR value comparing with the conve ntional receiver. Based on these results, it is shown that the BER of the p roposed receiver is lower than that of any other conventional receiver. The refore. using the newly suggested method, the considerable performance impr ovement can be obtained for the DS-CDMA systems.