Title :
Appropriate CCM-based algorithm for adaptive antenna array beamforming
Author :
Sadeghi, Hajar ; Moghaddam, Shahriar Shirvani ; Vakili, Vahid Tabataba
Author_Institution :
Tehran South Branch, Eng. Dept., Islamic Azad Univ., Tehran, Iran
Abstract :
Smart antenna is one of the most efficient and useful innovations in achieving maximum capacity, improved quality as well as coverage. In this investigation, we try to run a systematic comparison of the performance of different modified blind adaptive beamforming algorithms based on constrained constant modulus (CCM). Two of them use adaptive step size mechanisms, in the stochastic Gradient (SG) algorithm for adjusting the step size with low-complexity (CCM_SG_MASS, CCM_SG_TAASS). Other one is uses recursive least squares (RLS) type optimization algorithm (CCM_RLS) which is replaced by inverse of correlation matrix instead of step size. Simulations are implemented assuming uniform linear array (ULA) and 5 users that one of them is desired signal. Results revealed that modified algorithms, RLS_type, TAASS and MASS, offer higher performance respect to conventional CCM, respectively. Also RLS_type converges faster and it can cancel the interferences close to the desired signal better. Also the SINR level is higher and BER is less than other methods. However MASS and TAASS have less complexity.
Keywords :
adaptive antenna arrays; array signal processing; interference suppression; least squares approximations; optimisation; CCM_SG_MASS; CCM_SG_TAASS; adaptive antenna array beamforming; appropriate CCM-based algorithm; constrained constant modulus; interferences; linear array; modified blind adaptive beamforming algorithms; recursive least squares; smart antenna; stochastic gradient; Adaptive arrays; Adaptive beamforming techniques; constrained constant modulus (CCM); modified adaptive step size (MASS); recursive least squares (RLS); time averaging adaptive step size (TAASS);
Conference_Titel :
Telecommunications (IST), 2010 5th International Symposium on
Conference_Location :
Tehran
Print_ISBN :
978-1-4244-8183-5
DOI :
10.1109/ISTEL.2010.5734001