Performance of CDMA forward channels with random puncturing

In IS-95 and cdma2000 systems, some coded data symbols are randomly punctured after interleaving to provide a feedback path for power control of reverse link. The positions of the power control bits (PCB) are randomly selected within one power control group (PCG), and the number of punctured symbols is fixed within a frame. This can cause non-negligible performance degradation of the code used for the data channel. In this paper, we present a performance upper bound for the CDMA forward channels with convolutional codes and random puncturing from the average weight enumerator of the code. For long frames with many puncturing patterns, we also present a simple approximation to the performance.