Title :
Adaptive Microwave Beamforming Using High Weighting Rate and ULMS Algorithm
Author :
Farzaneh, S. ; Sebak, A.R.
Author_Institution :
Concordia Univ., Montreal, QC
Abstract :
In this work adaptive beamforming (ABF) is carried out for the general microwave beamformer using a new perturbation technique. For an L-element antenna array, the weight vector is perturbed L+1 times sequentially to obtain a noisy approximation of the antenna array signals for the gradient vector estimation. The process of weight perturbation is performed faster than the Nyquist rate to increase the temporal correlation between the signal samples in different perturbation cycles to decrease the gradient estimation error. The unconstrained least mean square (ULMS) algorithm is studied with the proposed perturbation technique. The proposed algorithm converges as fast as the corresponding digital beamforming algorithm in very low signal to noise ratio (SNR) and signal to interference ratio (SIR) conditions.
Keywords :
approximation theory; array signal processing; correlation methods; gradient methods; least mean squares methods; microwave antenna arrays; perturbation techniques; signal sampling; L-element antenna array; Nyquist rate; ULMS algorithm; adaptive microwave beamforming; digital beamforming algorithm; gradient vector estimation; noisy approximation; perturbation technique; signal sample; signal to interference ratio; signal to noise ratio; temporal correlation; unconstrained least mean square algorithm; Antenna arrays; Array signal processing; Cellular networks; Costs; Microwave theory and techniques; Perturbation methods; Phase shifters; Phased arrays; Signal processing; Signal to noise ratio;
Conference_Titel :
Vehicular Technology Conference, 2006. VTC-2006 Fall. 2006 IEEE 64th
Conference_Location :
Montreal, Que.
Print_ISBN :
1-4244-0062-7
Electronic_ISBN :
1-4244-0063-5
DOI :
10.1109/VTCF.2006.67
