Performance of Reverse-Link Packet Transmission in Mobile Cellular CDMA Networks

In this paper, a new pseudo noise (PN) code acquisition scheme for direct sequence spread spectrum (DS/SS) signals is proposed based on a joint decision rule of two correct cells ( cells) at which the code phase offset between the locally generated and received PN codes is within a desired small value. To derive the joint decision rule, the acquisition problem is modeled as a hypothesis testing problem and then the locally optimum (LO) test statistic is used for the problem. Finally, a novel acquisition technique is proposed based on the joint decision rule. The detection and mean acquisition time performances of the proposed acquisition scheme are analyzed and compared with those of a conventional acquisition scheme in which cells are individually used for detection. The numerical results show that the proposed scheme not only has better performance but also is more robust to the residual code phase offset variation than the conventional scheme.