EURASIP Journal on Wireless Communications and Networking
Volume 2007 (2007), Article ID 62379, 13 pages
doi:10.1155/2007/62379
Research Article
Power-Controlled CDMA Cell Sectorization with Multiuser Detection: A Comprehensive Analysis on Uplink and Downlink
Electrical Engineering Department, The Pennsylvania State University, 16802, PA, USA
Received 8 November 2006; Revised 14 July 2007; Accepted 12 October 2007
Academic Editor: Hyung-Myung Kim
Copyright © 2007 Changyoon Oh and Aylin 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.
Abstract
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 identify 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.