Patent ID: 7590083
Filing Date: 2009-09-15
Classification: H04B,Y02D

Abstract:
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, and said selected remote unit leaving said sleep mode and transmitting to said control station in response to said interrupt from said local source.