Application of antenna arrays to mobile communications. II. Beam-forming and direction-of-arrival considerations

TLDR

Array processing manipulates signals across multiple antenna elements to steer nulls, form independent beams, and estimate source directions, thereby offering a powerful tool for meeting the growing demands of mobile communications. This paper seeks to provide a comprehensive treatment of array signal processing, covering beam‑forming schemes, adaptive weighting algorithms, direction‑of‑arrival estimation methods, error impacts, and mitigation strategies. The authors analyze various beam‑forming configurations, adaptive weighting techniques, and direction‑of‑arrival estimation methods, compare their performance, assess error effects on array performance, and propose schemes to alleviate these errors. Part I demonstrated that appropriately configured arrays can enhance mobile communication performance, with supporting studies confirming the feasibility of such array systems.

Abstract

Array processing involves manipulation of signals induced on various antenna elements. Its capabilities of steering nulls to reduce cochannel interferences and pointing independent beams toward various mobiles, as well as its ability to provide estimates of directions of radiating sources, make it attractive to a mobile communications system designer. Array processing is expected to play an important role in fulfilling the increased demands of various mobile communications services. Part I of this paper showed how an array could be utilized in different configurations to improve the performance of mobile communications systems, with references to various studies where feasibility of apt array system for mobile communications is considered. This paper provides a comprehensive and detailed treatment of different beam-forming schemes, adaptive algorithms to adjust the required weighting on antennas, direction-of-arrival estimation methods-including their performance comparison-and effects of errors on the performance of an array system, as well as schemes to alleviate them. This paper brings together almost all aspects of array signal processing.