Convergence analysis of the least squares constant modulus algorithm in interference cancellation applications

Author

Biedka, Thomas E. ; Tranter, William H. ; Reed, Jeffrey H.

Author_Institution

Bradley Dept. of Electr. Eng., Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA

Volume

48

Issue

3

fYear

2000

fDate

3/1/2000 12:00:00 AM

Firstpage

491

Lastpage

501

Abstract

The convergence behavior of the least squares constant modulus (CM) algorithm in an adaptive beamforming application is examined. It is assumed that the desired signal and the interference are uncorrelated. The improvement in output signal-to-interference ratio (SIR) with each iteration of the algorithm is predicted for several different signal environments. Deterministic results are presented for an environment containing two complete sinusoids. Probabilistic results are presented for a CM desired signal with a CM interferer and with a Gaussian interferer. The asymptotic improvement in output SIR as the output SIR becomes high is also derived. The results of Monte Carlo simulations using sinusoidal, frequency modulation, and quadrature phase-shift keying signals are included to support the derivations

Keywords

Gaussian noise; Monte Carlo methods; adaptive antenna arrays; antenna theory; array signal processing; cochannel interference; convergence of numerical methods; frequency modulation; interference suppression; iterative methods; least squares approximations; quadrature phase shift keying; Gaussian interferer; Monte Carlo simulations; SIR; adaptive beamforming; convergence analysis; interference cancellation applications; iteration; least squares constant modulus algorithm; output signal-to-interference ratio; probabilistic results; quadrature phase-shift keying signal; sinusoidal frequency modulation; sinusoids; Adaptive algorithm; Adaptive arrays; Algorithm design and analysis; Array signal processing; Convergence; Frequency modulation; Frequency shift keying; Interference cancellation; Least squares methods; Phase shift keying;

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/26.837051

Filename

837051