LEO卫星通信系统中信道分配策略仿真

切换是LEO卫星移动通信系统中移动性管理的一个重要组成部分。LEO切换中的信道分配一般采用保护信道和各种排队方法相结合的策略。研究了多业务条件下LEO卫星通信系统越区切换中的信道分配策略，根据数据业务和话音业务的特点，提出了适用于LEO卫星通信系统的保护信道和强占优先相结合的信道分配策略。建立了一个简单而有效的LEO卫星通信系统切换模型，将新策略与传统的保护信道策略进行比较，仿真结果表明新策略以略微增加数据时延为代价换取了话音业务各项性能的极大改善。

Simulation of Channel Allocation Strategy in LEO Satellite Communication System

Handoff is an important part of mobile management in LEO satellite communication system. Generally speaking, integrated allocation strategies of reserving guard channel and all kinds of queuing are usually used in handoff of LEO system. Channel allocation strategy of handoff under conditions of multi - service in LEO satellite communication system is studied in this paper. Based on the characters of data - service and voice - service, an integrated reserving guard channel with preemptive priority channel allocation strategy suitable for LEO satellite communication system is proposed. A simple and effective model of handoff is set up. Through simulation, this new strategy is compared with that of pure reserving a number of channels, The simulation result shows that the new strategy can provide lower blocking probability for new voice calls and lower forced termination probability for ongoing voice calls, at the cost of little increase of average transmission delay for data calls.