In IEEE 802.16e wireless metropolitan area networks, users could take their broadband connections with them as they move from one location to another with different speeds. Providing QoS is more challenging for mobile subscribers at vehicular speeds than for others. On the other hand, time variability and unpredictability of the wireless channel may cause QoS degradation for these users. Therefore, providing seamless handovers especially at vehicular speeds is necessary for maintaining QoS. This paper proposes a new downlink handover priority scheduling algorithm for different scheduling services which is providing lossless handovers and QoS. Taking the power degradation rates into consideration, this algorithm assigns higher priority to the users who have higher speeds. A priority based AMC (Adaptive Modulation and Coding) is also performed for better performance. The analysis results show the efficiency of proposed scheme.

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