Document Type : Original Research Paper

Authors

1 Department of Electrical Engineering Iran University of Science and Technology (IUST),Tehran,Iran

2 Electrical Department of Technical and Engineering Shahid Rajaee Teacher Training University ,Tehran,Iran

Abstract

In this paper, in order to modify and improve the handoff process, which contains initiation and execution phases, three new prioritization schemes have been investigated. These new schemes prioritize handoff requests considering both traffic and propagation conditions. According to suggested schemes, priority of different candidate base-stations is based on three measurements in a joint state. These measurements are received power at mobile unit, power variation rates, and the number of free traffic channels of adjacent base-stations. Simulation results show that considering similar conditions, i.e. equal number of handoffs, lower call dropping (outage) and smaller delay distance will be achieved by new prioritization schemes rather than previous works. It means access to lower forced termination probability and interference and hence better QoS (Quality of Service). Finally, due to the best trade offs between propagation and traffic criteria, simulation results introduce SPBPS3 as optimum scheme.

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Main Subjects

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