摘要:
A satellite modem for broadband communication. The satellite modem receives a satellite signal on a single carrier from a satellite. The satellite signal is divided by time division multiplexing into physical sub-channels encapsulating logical downstreams. The satellite modem includes a filter which removes a subset of the physical sub-channels intended for the subscriber terminal. The satellite modem includes a demodulator, a decoder, and a medium access channel. The MAC processes the logical downstreams.
摘要:
A satellite system for broadband communication with a plurality of remote locations is described. The system includes a satellite and a plurality of service spot beams from the satellite. A plurality of forward channels are transported on carriers in the service spot beams. A plurality of sub-channels pass on the plurality of forward channels. The system further includes a plurality of independently managed domains, wherein the plurality of sub-channels are divided among the plurality of domains. The system may further include a plurality of satellite modems addressed by a plurality of service identifiers. Each of the plurality of service identifiers may be exclusively addressable within one of the plurality of domains.
摘要:
Upstream information arriving through a user terminal in a satellite link is efficiently scheduled through a modified Demand Assigned Multiple Access (DAMA) algorithm such that data packets arriving at the user terminal are concatenated to form a larger frame for transmission and the concatenated packet is held in a first queue disposed ahead of a second queue, where the data in the second queue cannot be modified (typically a hardware queue), sufficient to allow the second queue to be emptied. In a specific embodiment, all packets arriving at the user terminal since a prior piggyback request are concatenated so that all currently known packets (up to a preselected limit) are accounted for by each succeeding piggyback request. Since it is desirable to concatenate all packets that arrive at the user terminal since the last piggyback request, the piggyback request according to the invention covers all currently known packets (up to the preselected limit) in the user terminal. The held-back packets are released or dumped to the second queue by a trigger operative according to a map, the map being a grant allocation schedule. This mechanism handles instances where the second queue is not able to handle all known packets.
摘要:
Use of multi-user detection (MUD) with a frequency-multiplexed satellite return link (scheduling algorithms, etc) is described. The satellite return link may utilize multi-frequency time division multiple access (MF-TDMA). The satellite return link may include a plurality of return sub-channels, wherein one or more of the return sub-channels may operate in a contention mode during some time periods and a non-contention mode at different time periods.
摘要:
Use of multi-user detection (MUD) with a frequency-multiplexed satellite return link (scheduling algorithms, etc) is described. The satellite return link may utilize multi-frequency time division multiple access (MF-TDMA). The satellite return link may include a plurality of return sub-channels, wherein one or more of the return sub-channels may operate in a contention mode during some time periods and a non-contention mode at different time periods.
摘要:
Upstream information arriving through a gateway from a user terminal in a satellite link subject to propagation delay is efficiently scheduled through a modified Demand Assigned Multiple Access (DAMA) algorithm such that arriving data packets arriving at the software queue at the user terminal are concatenated to form a large frame for transmission to improve efficiency. A piggyback request replacing a conventional DAMA contention request for the succeeding packet is issued to request bandwidth allocation for the succeeding concatenated packet. In a specific embodiment, all packets up to the physical request limit arriving at the user terminal since a prior piggyback request or contention request are concatenated so that all currently known packets (up to that limit) are accounted for by the next piggyback request.
摘要:
Upstream information arriving through a user terminal in a satellite link is efficiently scheduled through a modified Demand Assigned Multiple Access (DAMA) algorithm such that data packets arriving at the user terminal are concatenated to form a larger frame for transmission and the concatenated packet is held in a first queue disposed ahead of a second queue, where the data in the second queue cannot be modified (typically a hardware queue), sufficient to allow the second queue to be emptied. In a specific embodiment, all packets arriving at the user terminal since a prior piggyback request are concatenated so that all currently known packets (up to a preselected limit) are accounted for by each succeeding piggyback request. Since it is desirable to concatenate all packets that arrive at the user terminal since the last piggyback request, the piggyback request according to the invention covers all currently known packets (up to the preselected limit) in the user terminal. The held-back packets are released or dumped to the second queue by a trigger operative according to a map, the map being a grant allocation schedule. This mechanism handles instances where the second queue is not able to handle all known packets.
摘要:
A satellite system for broadband communication with a plurality of remote locations is described. The system includes a satellite and a plurality of service spot beams from the satellite. A plurality of forward channels are transported on carriers in the service spot beams. A plurality of sub-channels pass on the plurality of forward channels. The system further includes a plurality of independently managed domains, wherein the plurality of sub-channels are divided among the plurality of domains. The system may further include a plurality of satellite modems addressed by a plurality of service identifiers. Each of the plurality of service identifiers may be exclusively addressable within one of the plurality of domains.
摘要:
A satellite system for broadband communication utilizing load balancing of satellite modems between physical forward sub-channels. The bandwidth requirements of the various satellite modems allocated to a domain are analyzed. Satellite modems, which can be moved between various physical forward sub-channels, are moved among physical forward sub-channels of a plurality of domains to balance loading between domains and/or physical forward sub-channels within domains. Buffering and latency are monitored in the subscriber modem termination system (SMTS) to allow dividing physical forward channel delay either uniformly or according to tiers of quality of service.
摘要:
In a data over satellite system, preallocation of upstream channel resources is provided by a scheduler at the gateway satellite modem termination system (SMTS) in response from the user terminal, wherein the user terminal detects web browser and/or bulk transfers involving large amounts of data transfer from users via the upstream channel. A type length value (TLV) field is included with data packets transmitted to the gateway SMTS, at which excess transfer capability is allocated to the user terminal in anticipation of load requirements.