الفهرس | Only 14 pages are availabe for public view |
Abstract In wireless mobile communication system ,there are some limitations that degrade the performance of these ,one of these limitations is fading of received signals due to multipath propagation over wireless channels .Multipath propagation is responsible of interference(ISI) which can be mitigated by a tapped line adaptive array (IDLAA) at the receiver .In addition ,TDLAA has the ability of suppressing co-channel interference (CCI) which is considered another limitation to the communication systems .TDLaa suffers rfom slow convergence rate to get the optimum performance ,it also requires a large computational complexity. To overcome these problems ,sub band adaptive array (SBAA)has been suggested tore place TDLAA operation is based on the idea of decomposing the frequency bund of the received signal into sub band which can be processed separately to get the optimum performance , this in turn decreases the computational complexity and improve the convergence characteristic In this thesis ,the fading channel characterizations are reviewed with a brief view on inter-symbol and co-channel interferences. To understand the operation of SBAA, the basic concepts of adaptive arrays are revied, followed by brief discussion on the basics of multi rate filters which decompose the frequency band of the of the received signal into sub bands to the improved performance of SBAA. |