A New Base Station Receiver for Increasing Diversity Order in a CDMA Cellular System

Abstract

Abstract-A new base station receiver is proposed and analyzed for a code-division multiple-access (CDMA) cellular system. The proposed receiver can achieve remarkable diversity gain by increasing diversity order with reasonable cost and complexity. From the numerical results, it is confirmed that the proposed receiver structure can be a practical solution for enhancing reverse-link capacity and improving performance in CDMA cellular system operations. The result in the letter can find its applications to legacy IS-95/cdma2000 1x base stations with simple modifications.Index Terms-Code-division multiple access (CDMA), diversity, multipath fading, receiver complexity.

Generalized performance analysis of a delay diversity receiver in asynchronous CDMA channels

“…In this section, we briefly describe the delay diversity receiver proposed in [7] in order to motivate the following performance analysis. In cellular CDMA systems, though the transmitted signal from a mobile station (MS) is spread by a 1536-1276/$20.00 © 2005 IEEE user-specific PN code, the received signals from the MS have different PN offsets due to the multipath components.…”

“…With this motivation, a delay diversity receiver was recently proposed and analyzed for synchronous CDMA channels [7]. This receiver attains the performance enhancements of the polarization and spatial diversity receiver [6], but with about half the complexity for the same diversity order.…”

“…In [7], the feasibility of the delay diversity receiver was verified through a performance analysis in synchronous CDMA channels. The paper made several simplifying assumptions such as 1) a synchronous link; 2) a frequency non-selective channel; and 3) constant and equal cross correlations.…”

“…Clearly, those assumptions are not valid in the uplink of a practical CDMA system. In this letter, we provide the complete and general performance analysis of the delay diversity receiver proposed in [7] with the recently developed framework of [8], [9]. In [8], [9] a Maximal Ratio Combining (MRC) receiver in asynchronous CDMA channels is accurately analyzed without many of the previously used compromising assumptions.…”

Performance of Energy Detection Spectrum Sensing with Delay Diversity for Cognitive Radio System

“…In order to overcome those shortcomings of the system with multiple antennas, the delay diversity receiver has been proposed and analyzed for synchronous CDMA channels in [25] and [26]. This receiver can achieve the performance enhancements of the polarization and spatial diversity receiver, but with about half the complexity for the same diversity order.…”