Transmit power control in fixed cellular broadband wireless systems

by Salamah, Salem

Broadband wireless access systems such as Local F.5uItipoint Communications Services (LMCS) is aiming to provide multimedia communication services to subscribers in fixed locations via millimeter wave transmissions at 28 GHz. In LMCS the total allocated frequency band is reused in each cell/sector through the use of highly directional antennas and polarization reuse in adjacent sectors. Some of the key issues in LMCS systems are the coverage and the cochannel interference. These problems have to be resolved before a successful deployment of such services. In this thesis, we implement two techniques that are known to combat CO-channel interference; these techniques are power control and rnacrodiversity. The objective of this research is to analyze the system performance of LMCS system using these techniques and under different scenarios. We will provide system designers with the appropriate power control command rate and power control step size. Furthemore, the effect of rnacrodiversity on system availability is investigated. A cornputer simulation program was developed and used to determine the system performance of the LlMCS network model. The results of the simulation are obtained and presented for different propagation environment and system parameters. The investigated parameters include the propagation exponent, logormal deviation, Rician K factor, correlation factor of fading channel, power control rate and step size.