An Adaptive Beam-Shaping Strategy for WCDMA Multicellular Networks with Non-Uniform Traffic Requirements

Abstract

This paper investigates the performance of an adaptive beam-shaping (ABS) strategy for wideband code division multiple access (WCDMA) multicellular networks with antenna arrays (AAs) at the base station (BS). The purpose of this ABS strategy is to form beams in directions of increased traffic distribution while at the same time minimize the total downlink transmission power. Performance is evaluated statistically with Monte Carlo (MC) simulations through a grid-enabled WCDMA system level simulator in terms of achievable throughput per beam for a network with up to four tiers of cells and increased loading (up to 90%). Results are presented for multirate services which show that the proposed ABS strategy can increase the throughput per beam relatively to a fixed grid of beams sectorization strategy up to 75/120/165% with 1/2/3 hotspots per cell respectively, while this gain is up to 35% for uniform traffic distribution. Moreover, it is shown that this gain can be achieved while at the same time the blocking probability in the central cell is reduced and the overall throughput of the network increased.