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Research Article Power-Controlled CDMA Cell Sectorization with Multiuser Detection: A Comprehensive Analysis on Uplink and Downlink | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2007 Article ID 62379 13 pages doi 2007 62379 Research Article Power-Controlled CDMA Cell Sectorization with Multiuser Detection A Comprehensive Analysis on Uplink and Downlink Changyoon Oh and Aylin Yener Electrical Engineering Department The Pennsylvania State University PA 16802 USA Received 8 November 2006 Revised 14 July 2007 Accepted 12 October 2007 Recommended by Hyung-Myung Kim We consider the joint optimization problem of cell sectorization transmit power control and multiuser detection for a CDMA cell. Given the number of sectors and user locations the cell is appropriately sectorized such that the total transmit power as well as the receiver filters is optimized. We formulate the corresponding joint optimization problems for both the uplink and the downlink and observe that in general the resulting optimum transmit and receive beamwidth values for the directional antennas at the base station are different. We present the optimum solution under a general setting with arbitrary signature sets multipath channels realistic directional antenna responses and identity its complexity. We propose a low-complexity sectorization algorithm that performs near optimum and compare its performance with that of optimum solution. The results suggest that by intelligently combining adaptive cell sectorization power control and linear multiuser detection we are able to increase the user capacity of the cell. Numerical results also indicate robustness of optimum sectorization against Gaussian channel estimation error. Copyright 2007 C. Oh and A. Yener. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION Future wireless systems are expected to provide high-capacity flexible services. Code division .