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Indexed by:期刊论文

Date of Publication:2008-12-01

Journal:IEEE TRANSACTIONS ON SIGNAL PROCESSING

Included Journals:SCIE、EI、Scopus

Volume:56

Issue:12

Page Number:6102-6106

ISSN No.:1053-587X

Key Words:Constant modulus; diagonal loading; robust beamforming

Abstract:The diagonal loading method is a simple and efficient method that improves the robustness of beamformers. However, determining an ideal diagonal loading factor (DLF) is not a trivial problem, one that still has not been adequately addressed. Although beamformers are widely used in radar, sonar, and many other applications, in this correspondence, we consider a beamformer used only for digital communication applications. In digital communications, user information is coded into a sequence with the constant modulus (CM) in the bawband. Obviously, if the beamformer can cancel interference sufficiently well, the outputs of the beamformer should satisfy the CM condition more precisely. Therefore, minimizing CM errors can act as a natural criterion for determining DLFs. In this correspondence, we present a cost function based on the criterion. We also propose a direct search algorithm for DLF determination by minimizing the cost function. Numerical experiments show the effectiveness of the proposed method.