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Satellites can broadcast datagram over a wide area, even to the areas that cannot be well served by the existing terrestrial infrastructures. Therefore, it is a hot research topic about how to multicast datagram over satellites. Low Earth Orbit (LEO) satellites have short round-trip delay and low power consumption, it will be an essential part of future multimedia communication application. In this paper, we proposed a multicast routing for LEO satellite constellation networks with high performance. The algorithm uses the group members' geographic information to route multicast packets, with less memory, computer power and signaling overhead. Through simulation we evaluate the delay and performance of our algorithm. [ABSTRACT FROM PUBLISHER]

Satellite networks can provide worldwide-coverage wireless data gram services, but cause great challenges for how to efficiently route data gram. The Low Earth Orbit (LEO) satellite is becoming an essential part of the Next-Generation internet with short round-trip delay and low power consumption. In this paper, we propose a routing algorithm for LEO satellite constellation networks with high performance. It needs less memory and computer power, but is capable of highly efficient data gram route. Through simulation we demonstrate the performance of the proposed algorithm. Moreover, we integrate the IP protocol into the algorithm to prove its deploy ability. [ABSTRACT FROM PUBLISHER]

Satellite systems play an important role in current global communications. New generations of satellite systems can utilize so called multilayered configurations where satellites among various layers (orbits) are interconnected to increase a capacity of overall system. Such satellite systems need to find optimal protocols (e.g. routing protocols) and optimal number of interlayer links. In this paper, we present and analyze latter aspect for two-layer satellite networks/systems based on end-to-end packet delays. We evaluate by simulations how interlayer interconnectivity influences final packet delays and we also show that full interconnectivity is not necessary to achieve acceptable results. [ABSTRACT FROM PUBLISHER]

Recently, Non-Geostationary Earth Orbit (NGEO) satellite networks have gained research attention. Since they offer many features, e.g., extensive coverage, disaster-resistance, and efficient power consumption, they are considered as a good candidate for providing global communication services. Moreover, Multi-Layered Satellite Networks (MLSNs), which consist of layered NGEO satellite networks, have attracted much attention since they achieve excellent load distribution through bypassing traffic from the lower layer to upper layer. However, there is a possibility that traffic congestion may exist at a satellite on the upper layer because each satellite on the upper layer usually covers more than one satellite on lower layers in MLSNs. In this paper, we focus on traffic control in two-layered networks, especially on distributing the packet flow between the two layers in order to minimize the transfer delay of the network. Simulation results demonstrate the correctness of our analyses about delay in the network. [ABSTRACT FROM PUBLISHER]

Observation of active fires enables the estimation of trace gas and aerosol emissions, and can support fire management, air pollution monitoring and forecasting, and reporting efforts under international conventions. Here we present a mission concept for a dedicated Fire Monitoring Constellation (FMC) of small satellites based on experience from the BIRD mission (2001 – 2004), as well as the upcoming FireBIRD mini-constellation to start operating in 2014. An operational FMC should provide near daily observations during afternoon hours, improve characterisation and monitoring of fires in the low latitudes, and provide high spatial resolution to characterize fire fronts and predominant combustion regime. [ABSTRACT FROM PUBLISHER]

We present a family of adaptive constellations that, in a nonlinear optical fiber channel model, has a mutual information (modulation-constrained capacity) that does not decrease with signal power [ABSTRACT FROM PUBLISHER]