Wireless packet data distributed communications system
First Claim
1. A method of communication between a control station and a plurality of remote units having respective remote unit addresses by way of a two-way satellite, said method comprising:
- said control station transmitting both a remote unit address and data packets of information over a single TDM carrier signal to a selected remote unit of said plurality of remote units during a preprogrammed awake subframe assigned to said selected remote unit via said two way satellite,said selected remote unit leaving a sleep mode during which it is inactive and entering an active mode during which it is capable of receiving said data packets of information,monitoring said single TDM carrier signal by said selected remote unit when said selected remote unit enters said active mode to search for its respective remote unit address,if said selected remote unit detects its respective remote unit address said selected remote unit receiving said data packets of information from said control station during said preprogrammed awake subframe by way of said single TDM carrier signal,wherein said control station transmits a subframe change message during said preprogrammed awake subframe and said selected remote unit changes a time of its awake subframe in response to said subframe change message to provide a changed awake subframe differing from said preprogrammed awake subframe,said selected remote unit waking up during a subsequent occurrence of said changed awake subframe and determining whether it is being addressed,said selected remote unit receiving further data packets of information from said control station during said subsequent occurrence of said changed awake subframe,transmitting data packets of information by said selected remote unit to said control station over a slotted CDMA return link in accordance with said detecting of its respective address,said selected remote unit receiving an interrupt from a local source while in said sleep mode, andsaid selected remote unit leaving said sleep mode and transmitting to said control station in response to said interrupt from said local source.
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Accused Products
Abstract
A two-way satellite communications system includes an Earth station communicating with a plurality of remote terminals using a network access protocol that facilitates low power consumption by the terminals. The earth station generates forward link TDM packet data transmissions on one or more satellite channels, and detects, despreads and decodes multiple concurrent return link slotted CDMA packet transmissions on one or more satellite channels. It communicates through a wired connection with a packet processing center which ultimately both delivers return link packet data to end-customers and receives forward link packet data from end-customers. The remote terminals receive, process and act upon forward link TDM transmissions on one or more satellite channels, and generate slotted spread spectrum CDMA transmissions on the return link on one or more satellite channels. The remote terminals communicate with a local digital data source and/or sink, digitize one or more local analog sensor signals, enter into a sleep mode to minimize the terminal'"'"'s power consumption, and access the satellite communications network in accordance with the system network access protocol.
117 Citations
72 Claims
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1. A method of communication between a control station and a plurality of remote units having respective remote unit addresses by way of a two-way satellite, said method comprising:
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said control station transmitting both a remote unit address and data packets of information over a single TDM carrier signal to a selected remote unit of said plurality of remote units during a preprogrammed awake subframe assigned to said selected remote unit via said two way satellite, said selected remote unit leaving a sleep mode during which it is inactive and entering an active mode during which it is capable of receiving said data packets of information, monitoring said single TDM carrier signal by said selected remote unit when said selected remote unit enters said active mode to search for its respective remote unit address, if said selected remote unit detects its respective remote unit address said selected remote unit receiving said data packets of information from said control station during said preprogrammed awake subframe by way of said single TDM carrier signal, wherein said control station transmits a subframe change message during said preprogrammed awake subframe and said selected remote unit changes a time of its awake subframe in response to said subframe change message to provide a changed awake subframe differing from said preprogrammed awake subframe, said selected remote unit waking up during a subsequent occurrence of said changed awake subframe and determining whether it is being addressed, said selected remote unit receiving further data packets of information from said control station during said subsequent occurrence of said changed awake subframe, transmitting data packets of information by said selected remote unit to said control station over a slotted CDMA return link in accordance with said detecting of its respective address, said selected remote unit receiving an interrupt from a local source while in said sleep mode, and said selected remote unit leaving said sleep mode and transmitting to said control station in response to said interrupt from said local source. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58)
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59. A system for communication between a control station and a plurality of remote units having respective remote unit addresses by way of a two-way satellite, said system comprising:
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a single TDM carrier transmitted by said control station to a selected remote unit via said two way satellite of said plurality of remote units during a preprogrammed awake subframe assigned said single TDM carrier carrying both a remote unit address and data packets of information, a sleep mode during which said selected remote unit is inactive an active mode entered by said selected remote unit during said preprogrammed awake subframe during which said selected remote unit monitors said single TDM carrier signal to search for its respective remote unit address, and during which said selected remote unit is capable of receiving said data packets of information by way of said single TDM carrier signal if said selected remote unit detects its respective remote unit address, a changed awake subframe of said selected remote unit differing from said preprogrammed awake subframe wherein said selected remote unit changes a time of its awake subframe in response to a subframe change message transmitted by said control station, said selected remote unit waking up during a subsequent occurrence of said changed awake subframe and determining whether it is being addressed, further data packets of information received by said selected remote unit from said control station during said subsequent occurrence of said changed awake subframe, transmitted data packets of information transmitted by said selected remote unit to said control station over a slotted CDMA return link in accordance with said detecting of its respective address, an interrupt received by said selected remote unit from a local source while in said sleep mode, and a transmission from said selected remote unit to said control station in response to said interrupt from said local source. - View Dependent Claims (60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72)
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Specification