The Research On Beamforming Algorithms Of Smart Antenna

Smart antennas technique is a primary development direction of future wirelesscommunication systems. How to cancel co-channel interference, multi-accessinterference,andcombat themulti-pathsfadingeffects,aremajorfactorsneededtobeconsidered, when people attempt to enhance the communication system. Smartantennas system, which introduces advanced adaptive array processing, producesspace beams whose main beam directs at the direction of desired user, null steeringbeams directing at the direction of interference, thus suppressing or canceling theinterfering signals, therefore, it can improve the signal-to-interference ratio andsystem capacity.Recently, the smart antennas technique is one of the hottest researchtopicsinmobilecommunicationareaasasolutiontothefrequencylack.The principle of smart antenna and its uaual structure are firstly introduced in thispaper and then we disscuss the signal models of antenna arrays.Secondly we describesome familia convergent rules of smart antenna and some beamforming algorithmsbase on these rules, such as LMS, RLS, CMAand MUSIC algorithms are illuminatedat length. And then we emluated them with computer, we find their advantages andshortcomings, and then we give their applications in the future.Thirdly we proposesome classic advanced beamforming algorithms, such as advanced SVSLMSalgorithms,optimized step-length RLS algorithm and adjustable CMA algorithm.wesimuate these algorithms with computer and find their advantages.Finally we discussthe feasibility of realizing smart antenna at mobile terminals (especially mobilephones), and then we present two possible structures of smart antenna after wediscussing the array numbers and array distance. At the same time we propose a newhalf-blind algorithm which references two of the advanced algorithms we giveabove.After we simulated it with computer, we find out since it has the merits of thetwo advanced algorithms,it is more feasible and more robust than any of thetraditionalalgorithmsforsmartantennaatmobileterminals.This paperhaveits own pertinency,it canbelookedat a good guidetothe researchofsmart antenna,at thesametimeit is ofgreat valueinengineeringapplicationinthefuture.