Studying behavior of the Gradient Signal Processing Algorithm for Adaptive Antenna Arrays in Telecommunication Environment

Peculiarities of telecommunication environment are considered and their implications for adaptive antenna array applications in mobile systems are analyzed. Most of the up-to-day research of adaptation methods in antenna arrays has been done on assumption that interfering signals are best described as stationary noise processes with Gaussian probability distribution. While that might be true for radar applications, interfering signals in mobile telecommunications are of the different nature. They are less random and this limited randomness varies depending on the modulation and multiplexing method. Previously, the novel gradient adaptation method developed by the authors was tested and shown to exhibit very promising behavior in only Gaussian noise environment. To assess its suitability for telecommunications, the algorithm was tested in the setting whereby interfering signals are presented as those with the typical mobile modulations, namely BPSK, QPSK and 8PSK. Contrary to the assumption that more regular structure of these signals can lead to some inter-signal correlation with accompanying performance degradation, it is shown that the designed algorithm behaves well and secures required performance expectations. Computer simulation of adaptive antenna arrays based on the algorithm using signals with BPSK, QPSK and 8PSK was carried out. It confirms high performance of the gradient algorithm in those situations and presents it as a good choice for mobile applications.