On the Selection of Partial Cancellation Factors for a Hard-Decision Partial PIC Scheme in DS-CDMA Systems

In this letter, we present a simple method of selecting the partial cancellation factor (PCF) for the first stage of a hard-decision partial parallel interference cancellation detector for direct-sequence code-division multiple access (DS-CDMA) systems. Using Price's theorem, we derive a range of the optimal PCF, where the lower and upper boundary values can be explicitly calculated from the processing gain and the number of users of the DS-CDMA system. Computer simulation results show that, using the average of these two boundary values as the PCF for the first stage, the bit error rate performance closely approximates that of the real optimal PCF.