This dissertation discusses cell planning, mobile location estimation and handover decision for cellular communication systems. First, this dissertation presents background noise measurements in urban Taipei city for the deployment of WCDMA (wideband code division multiple access) systems. The level of spectrum pollution is evaluated by using statistical parameters. Based on the measurements, a better solution using a genetic algorithm is proposed for the system deployment. Secondly, this dissertation presents the SADOA (Signal attenuation difference of arrival) location method. Each SADOA measurement yields a circle along which the MS (mobile station) may lie and multiple circles intersect at the estimated MS position. The SADOA method is combined with the TDOA (time difference of arrival) method to enhance the accuracy and penetration of location ability. The results of driving measurement show that the proposed location methods outperform the conventional methods in a GSM (global system for mobile communications) system. Finally, this dissertation discusses handover decision based on the MS mobility. The proposed algorithm makes necessary hard handovers by ascertaining the signal variation is dominated by path loss. This dissertation also presents a soft handover algorithm, which adds two hysteresis parameters including the MS distance and heading direction. Besides, this dissertation presents an efficient GSM/WCDMA intersystem handover algorithm, which considers the reliability of communication link, evaluated from the MS distance. Compared to conventional methods, the results show that the proposed algorithms reduce the number of unnecessary handovers and the mean size of active set while remain similar signal outage probability and increase data throughput in a real network.
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