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Special issue on satellite communication systems and networking
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Guest Editorial: Satellite Systems, Applications and Networking.
yesGuest Editorial of Special Issue (featuring eight original papers, comprising 133 pages in total). Whilst satellite systems continue to be at the forefront of broadcast communication
service provision, they have an increasingly important role to play in the provision of
global Internet services. There has been a strong trend towards convergence of
communication services in recent times, with the Internet providing the ideal platform
on which to base such convergence. Even traditional circuit-switched applications
(such as voice and video streaming) have been shown to work effectively over the
Internet. Although the Internet is prevalent in the developed world, satellites are vital
to extending this into more remote and sparsely populated regions of the world. It is
therefore important that satellite technology is advanced to provide seamless
interoperability with the Internet and adequate Quality of Service (QoS) support. The
purpose of this special issue is to present research devoted to furthering satellite
technology and networking to support the provision of both current and future
applications
Proactive TCP mechanism to improve Handover performance in Mobile Satellite and Terrestrial Networks
Emerging standardization of Geo Mobile Radio (GMR-1) for satellite system is
having strong resemblance to terrestrial GSM (Global System for Mobile
communications) at the upper protocol layers and TCP (Transmission Control
Protocol) is one of them. This space segment technology as well as terrestrial
technology, is characterized by periodic variations in communication properties
and coverage causing the termination of ongoing call as connections of Mobile
Nodes (MN) alter stochastically. Although provisions are made to provide
efficient communication infrastructure this hybrid space and terrestrial
networks must ensure the end-to-end network performance so that MN can move
seamlessly among these networks. However from connectivity point of view
current TCP performance has not been engineered for mobility events in
multi-radio MN. Traditionally, TCP has applied a set of congestion control
algorithms (slow-start, congestion avoidance, fast retransmit, fast recovery)
to probe the currently available bandwidth on the connection path. These
algorithms need several round-trip times to find the correct transmission rate
(i.e. congestion window), and adapt to sudden changes connectivity due to
handover. While there are protocols to maintain the connection continuity on
mobility events, such as Mobile IP (MIP) and Host Identity Protocol (HIP), TCP
performance engineering has had less attention. TCP is implemented as a
separate component in an operating system, and is therefore often unaware of
the mobility events or the nature of multi-radios' communication. This paper
aims to improve TCP communication performance in Mobile satellite and
terrestrial networks.Comment: 5 pages, 2 figure
DVB-RCS return link radio resource management for broadband satellite systems using fade mitigation techniques at ka band
Current Broadband Satellite systems supporting DVB-RCS at Ku band have static physical layer in order not to complicate their implementation. However at Ka band frequencies and above an adaptive physical layer wherein the
physical layer parameters are dynamically modified on a per user basis is necessary to counteract atmospheric attenuation. Satellite Radio Resource Management (RRM) at the Medium Access Control (MAC) layer has become an important issue given the emphasis placed on Quality of Service (QoS) provided to the Users. The work presented here tackles the problem of Satellite RRM for Broadband Satellite systems using DVB-RCS where a fully adaptive physical layer is envisaged at Ka band frequencies.
The impact of adaptive physical layer and user traffic conditions on the MAC layer functions is analyzed and an algorithm is proposed for the RRM process. Various physical layer issues associated with the resource management problem are also analyzed
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