Katsuya Nakahira

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To obtain large capacity, high quality future mobile satellite communication systems, we must use a multi-beam that has extremely high levels of frequency reuse. This paper describes a novel resource allocation scheme for multi-beam satellite communication systems that can dynamically offer maximum communication capacity without compromising quality. The(More)
Delay-tolerant networks (DTNs) are a promising network architecture which can provide reliable multi-hop message transmission between participating mobile nodes in an unfavorable environment that is prone to link disruption and disconnection by replicating and relaying messages without any need of physical infrastructure. Additionally, DTNs can also operate(More)
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We propose an efficient channel control scheme for gathering data from many observation points scattered over an ultra-wide area using a satellite communication system. There are a huge number of observation points, and the data packets to be transmitted are relatively short. To implement the system economically, the proposed scheme is expected to manage(More)