Title :
Phase-only LMS and perturbation adaptive algorithms
Author :
Davis, Richard M.
Author_Institution :
Mitre Corp., Bedford, MA, USA
fDate :
1/1/1998 12:00:00 AM
Abstract :
The author defines a phase-only gradient-based adaptive algorithm analogous to the least mean square (LMS) algorithm. Two phase-only perturbation algorithms are then defined. It is shown that the gradient for the perturbation algorithms can be obtained by cross-correlating binary perturbation sequences, that are applied to the adaptive phases, with the resulting instantaneous output power or voltage. It is also shown that a single set of phase-only adaptive weights can be used to simultaneously null interference in multiple output beams. Simulation results are presented for all of the new algorithms. The phase-only perturbation techniques eliminate the need for element level receivers and support low cost retrofitting of adaptive nulling on phased arrays by using conventional beamsteering circuits to apply the adaptive weights
Keywords :
adaptive antenna arrays; adaptive signal processing; antenna radiation patterns; antenna theory; least mean squares methods; numerical analysis; perturbation techniques; adaptive nulling; adaptive weights; beamsteering circuits; binary perturbation sequences; cross-correlation; instantaneous output power; instantaneous output voltage; interference; least mean square algorithm; low cost retrofitting; multiple output beams; perturbation adaptive algorithms; phase-only adaptive weights; phase-only gradient-based adaptive algorithm; phase-only perturbation algorithms; simulation; Adaptive algorithm; Adaptive arrays; Circuit simulation; Costs; Interference; Least squares approximation; Perturbation methods; Phased arrays; Power generation; Voltage;
Journal_Title :
Aerospace and Electronic Systems, IEEE Transactions on