低轨卫星网络能够为用户提供全球范围的宽带接入服务，是目前卫星通信网络的主要发展方向。然而低轨卫星平台资源受限、地面业务分布不均匀，给星地接入方案设计带来诸多挑战。提出宽波束结合动态点波束的跳波束接入方案，由宽波束获取信令信息，辅助点波束进行跳波束按需服务用户业务的通信方案。针对不同用户分布场景，使用迭代算法进行仿真，验证相对于传统固定多波束方案，宽波束结合动态点波束的跳波束方案在用户分布不均匀的情况下，能达到更高的系统吞吐性能，且业务量小时具有更好的时延性能等。
Low earth orbit (LEO) satellite networks have become the promising approach to provide broadband internet access service and have attracted the interests from both academy and industry. In this paper we review the related work of beam-hopping and find that most of the existing beam-hopping schemes are designed for GEO satellites and cannot be used for LEO satellites. Therefore, the beam-hopping system for the LEO mega-constellation is constructed in this worh. Due to the limited onboard resource and uneven traffic demand distribution, we propose a wide beam combined with dynamic beam-hopping scheme, which acquires signaling information from a wide beam to assist the spot beam to perform a communication scheme of the beam hopping on-demand service. The simulation results show that the beam-hopping scheme achieves better throughput performance than the fixed-beam scheme when the traffic demand distribution is uneven.
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