Coordination in a Multi-Cell Multi-Antenna Multi-User W-CDMA System: A Beamforming Approach

• Published in: IEEE transactions on wireless communications 2008-11, Vol.7 (11), p.4479-4485
• Main Authors: Botella, Carmen, Pinero, Gema, Gonzalez, Alberto, De Diego, Maria
• Format: Article
• Language: English
• Subjects: Algorithm design and analysis; Algorithms; Antennas; Applied sciences; Array signal processing; Base stations; Beamforming; Coordinated multi-cell system; Design engineering; Detection, estimation, filtering, equalization, prediction; Downlink; downlink multi-basebeamforming; Equalizers; Exact sciences and technology; Information, signal and communications theory; joint power control and optimal beamforming algorithms; Matched filters; multi-base scheduling techniques; Multiaccess communication; Operation, maintenance, reliability; Optimization; Power control; Quality of service; Radiocommunications; Receivers; Scheduling algorithm; Signal and communications theory; Signal, noise; Stations; Studies; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Wireless communication
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/T-WC.2008.070844

The problem of designing joint power control and optimal beamforming (JPCOB) algorithms for the downlink of a coordinated multi-cell WCDMA system is considered throughout this paper. In this case, the JPCOB design is formulated as the problem of minimizing the total transmitted power in the coordinated multi-cell system, subject to a certain quality of service requirement for each user. In this paper, the performance of two JPCOB algorithms based on different beamforming approaches is compared over the coordinated multi-cell system. The first one, obtains local beamformers by means of the well-known virtual uplink-downlink duality. In contrast, the second algorithm implements multi-base beamformers, taking into account match filter equalizers at the receivers. Moreover, realistic system parameters, such as per-base station power constraints or the asynchronous nature of the signals arriving at the receivers, are taken into account. Simulation results show that the algorithm based on multi-base beamforming presents attractive properties, such as an inherent multi-base scheduling technique or a decreasing total transmitted power as the degree of coordination between base stations is increased.