Title :
Space fitting the uncorrelated interference patterns in constrained adaptive antenna arrays using neural networks
Author :
Elkamchouchi, Hassan M. ; Zamzam, Wessam F.
Author_Institution :
SRD Dept., Alcatel Egypt, Egypt
Abstract :
An adaptive array antenna adjusts its element weightings so as to null out interference signals while maintaining a beam in the desired signal direction. This process of nulling out interferers has a constraint represented by the limited degrees of freedom. This puts limits on the number of requirements an array can achieve at a particular time. For instance, an N-element antenna array has N-1 degrees of freedom in its pattern. So if there are more interferers we need an array with a large number of elements. But here, we stop thinking about interferers as individual spot sources and we take into consideration their space distribution, their positions as long as their relative strengths, this is accomplished by constructing a general interference pattern and then studying this pattern to determine the optimal null positions. Next, the neural networks technique is used to adjust the array weights with their optimal values, which will give a general array pattern to meet the specified requirements. The previous process is fully described and illustrative examples are introduced
Keywords :
adaptive antenna arrays; adaptive signal processing; antenna radiation patterns; electrical engineering computing; interference suppression; neural nets; antenna array pattern; array weights adjustment; constrained adaptive antenna arrays; element weightings; general interference pattern; interference signals nulling; interferer space distribution; neural networks; optimal null positions; signal direction; space fitting; uncorrelated interference patterns; Adaptive arrays; Antenna arrays; Bellows; Directive antennas; Gaussian distribution; Intelligent networks; Interference constraints; Jamming; Neural networks; Polynomials;
Conference_Titel :
Radio Science Conference, 2001. NRSC 2001. Proceedings of the Eighteenth National
Conference_Location :
Mansoura
Print_ISBN :
977-5031-68-0
DOI :
10.1109/NRSC.2001.929175