Studying of Useful Signal Impact on Convergence Parameters of the Gradient Signal Processing Algorithm for Adaptive Antenna Arrays that Obviates Reference Signal Presence

Abstract

Signal processing algorithms in adaptive antenna arrays are analyzed with respect to their application in mobile telecommunication systems. It is established that both in literature and in practice insufficient attention is paid to search for and design of such simple adaptation algorithms that do not require presence of the reference signal. A simple algorithm of antenna array adaptation was earlier deduced that operates in the absence of the reference signal. Its successful testing was carried out under assumptions that the useful signal in the adaptive antenna array does not have an impact on the adaptation process. This assumption is valid for radar applications with short duration useful signals but not necessarily applicable for telecommunication systems with continuous ones. To address these limitations, influences of the useful signal on the algorithm convergence parameters are studied. Computer simulation of adaptive antenna arrays with the designed algorithm with account of useful signal impact in different situations is performed. It is shown that with some adjustments of the constant that determines the adaptation step, the impact of continuous useful signals on the designed gradient algorithm convergence performance can be greatly mitigated.