Weight Vector Fluctuations in Adaptive Antenna Arrays Tuned Using the Least-Mean-Square Error Algorithm with Quadratic Constraint

• Published in: Radiophysics and quantum electronics Vol. 58; no. 1; pp. 71 - 77
• Main Author: Zimina, S. V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2015; Springer; Springer Nature B.V
• Subjects: Adaptive antenna arrays; Algorithms; Amplification; Analysis; Antennas; Antennas (Electronics); Astronomy; Astrophysics and Astroparticles; Covariance matrix; Fluctuation; Hadrons; Heavy Ions; Lasers; Mathematical analysis; Mathematical and Computational Physics; Nuclear Physics; Observations and Techniques; Optical Devices; Optics; Permissible error; Photonics; Physics; Physics and Astronomy; Quantum Optics; Theoretical; Weight Vector; Quadratic Constraint; Antenna Array; Output Signal; Correlation Function
• ISSN: 0033-8443; 1573-9120
• DOI: 10.1007/s11141-015-9582-5

We present the results of statistical analysis of an adaptive antenna array tuned using the least-mean-square error algorithm with quadratic constraint on the useful-signal amplification with allowance for the weight-coefficient fluctuations. Using the perturbation theory, the expressions for the correlation function and power of the output signal of the adaptive antenna array, as well as the formula for the weight-vector covariance matrix are obtained in the first approximation. The fluctuations are shown to lead to the signal distortions at the antenna-array output. The weight-coefficient fluctuations result in the appearance of additional terms in the statistical characteristics of the antenna array. It is also shown that the weight-vector fluctuations are isotropic, i.e., identical in all directions of the weight-coefficient space.