Title :
A novel adaptive LMS-based algorithm considering relative velocity of source
Author :
Moghaddam, Shahriar Shirvani ; Moghaddam, Mahyar Shirvani ; Rad, Roohollah Kalami
Author_Institution :
Dept. of Electr. & Comput. Eng., Shahid Rajaee Teacher Training Univ., Tehran, Iran
Abstract :
In this paper a new least mean square (LMS) based adaptive weighting algorithm is proposed. It is appropriate for antenna array systems with moving targets and mobile applications. The essential goal of this algorithm is to reduce the complexity of weighting process and to decrease the time needed for adjusting the antenna radiation pattern. The main lobe of antenna will be adjusted in the direction of desired signal (main signal) and nulls pointed in the direction of undesired signals (interference signals). By predicting the relative velocity of source, the next location of the source will be estimated and the array weights will be determined using LMS algorithm before arriving to the new point. For the next time associated to the new sampling point, evaluated weights will be used. Furthermore, by updating these weights between two consecutive times the effects of error propagation will be eliminated. Therefore, in addition to reduction in computational complexity at the time of weight allocation, relatively accurate weight allocation can be obtained. Simulation results show that the angular error related to proposed LMS-based algorithm is similar to the conventional LMS algorithm at different signal to noise ratios (SNRs). On the other hand, online computational complexity of new algorithm is slightly less than previous one.
Keywords :
adaptive antenna arrays; antenna radiation patterns; communication complexity; least mean squares methods; adaptive LMS-based algorithm; antenna array system; antenna lobe; antenna radiation pattern; computational complexity; error propagation; least mean square based adaptive weighting algorithm; moving target; sampling method; source relative velocity; Algorithm design and analysis; Antenna radiation patterns; Array signal processing; Arrays; Least squares approximation; Prediction algorithms; Signal processing algorithms;
Conference_Titel :
Communication Systems Networks and Digital Signal Processing (CSNDSP), 2010 7th International Symposium on
Conference_Location :
Newcastle upon Tyne
Print_ISBN :
978-1-4244-8858-2
Electronic_ISBN :
978-1-86135-369-6