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公开(公告)号：EP0764349B1
公开(公告)日：2001-08-22
申请号：EP95924399.9
申请日：1995-06-06
Applicant: Inmarsat Ltd.
Inventor： FELDMAN, Howard, Ray
Abstract: A map is provided for indicating the direction of a fixed point (S), such as a sub-satellite point, from any point (P) within a specified area which is a substantial fraction of the earth's surface. The map projection is such that the actual direction to the fixed point (S) is the same as the direction shown on the map, when the map is aligned with a reference direction such as magnetic north. Optionally, the distance to the fixed point on the map represents the elevation of the satellite. Apparatus for using the map includes a holder (10) for the map and for a magnetic compass (18). A scale (22) which rotates about the fixed point on the map has a marker (32) which is positioned over the user's location on the map. The azimuthal direction of the satellite is indicated by an arrow (28) on the scale, while the elevation of the satellite is read off the scale by means of a pointer (34) located on the fixed point on the map.
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公开(公告)号：EP0843918B1
公开(公告)日：2000-09-27
申请号：EP96925885.4
申请日：1996-07-26
Applicant: Inmarsat Ltd.
Inventor： FEBVRE, Paul , PHILLIPS, Kevin
CPC classification number: H04B7/2041 , H04B7/1855
Abstract: A mobile terminal (6) communicates via a satellite (8), which projects a number of overlapping spot beams (10), with a fixed earth station (2). To determine which spot beam (10) is to be used for communication, the mobile terminal signals in a common signalling channel which is simultaneously received by all, or a subgroup of, the spot beams (10). The satellite (8) retransmits to the fixed earth station (2) in separate channels the signal as received by each of the spot beams (10) which are able to receive the common signalling channel. The relative strengths of the signal as received in the different spot beams (10) are compared at the fixed earth station and a communications channel is assigned to the mobile terminal in one of the spot beams (10), selected according to the comparison of signal strengths.
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公开(公告)号：EP0756762B1
公开(公告)日：2000-01-19
申请号：EP95913277.0
申请日：1995-03-30
Applicant: Inmarsat Ltd.
Inventor： MUNOZ-GARCIA, Samuel , NOMOTO, Shinichi , POSKETT, Peter , MULLINS, Dennis , HUTCHINSON, Ben , CHOMET, Patrick
CPC classification number: H01Q25/00 , H01Q1/288 , H01Q3/26 , H01Q3/40 , H01Q21/22 , H04B7/2041 , Y02D70/122 , Y02D70/446
Abstract: A communications station for generating or receiving an angularly dispersed array of radiation beams, comprising an array of radiating elements (100) defining an array antenna (1); and a beam former (120), the beam former comprising a passive network having a first side (X) carrying a plurality of beam ports for electrical signals corresponding to the beams and a second side (Y) carrying a plurality of antenna ports corresponding to the radiating elements, each beam port being connected to a plurality of antenna ports via a network (50) of power divider (52) and phase shifter (53) components, the phase shifts of which are in integer multiples of a predetermined constant, so as to generate the array of beams; in which the array antenna (1) has triangular or hexagonal symmetry and the array of beams has triangular or hexagonal symmetry.
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公开(公告)号：DE69738644T2
公开(公告)日：2009-05-28
申请号：DE69738644
申请日：1997-12-04
Applicant: INMARSAT LTD
Inventor： HARPER JOHN ANTHONY , MACRIDIS PHILIP
IPC: H04B7/26 , H04J3/00 , H04B7/185 , H04B7/212 , H04J3/16 , H04L12/70 , H04Q11/04 , H04W4/00 , H04W16/28 , H04W28/20 , H04W60/00 , H04W72/04 , H04W74/04 , H04W76/02 , H04W76/06 , H04W84/06 , H04W99/00
Abstract: A satellite communications system provides a communications service to a mobile terminal (2) on which different communications applications (4a to 4d) may be run. Calls are set up between any of the applications (4a to 4d) via a satellite (12) to a network management centre (18) which provides different service adaptors (20a to 20d) which adapt the calls to different types of service provided over terrestrial networks (22), such as telephony, facsimile, internet or ATM services. The bandwidth allocated to each call over the satellite link may be varied during the call according to demand either from the relevant application (4) or from the network management centre (18). Multiple calls may be connected concurrently to or from different applications running on the mobile terminal. A maximum bandwidth is allocated to each call. Efficient use is thereby made of the limited bandwidth available over the satellite (12), according to the instantaneous bandwidth requirements of different applications (4). For real-time calls requiring multiple slots per frame in a TDMA channel, the slots are mutually spaced apart to reduce delay.
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公开(公告)号：DE69938399T2
公开(公告)日：2009-03-05
申请号：DE69938399
申请日：1999-11-12
Applicant: INMARSAT LTD
Inventor： FEBVRE PAUL , MUDGE DAVID DENIS , JONES EDWARD ARTHUR , FINES PANAGIOTIS
Abstract: To demodulate the received bursts correctly, the timing of reception of the bursts is predicted by a receive timing controller (29) which receives the frame timing control information from the frame timing function (14) and parameters of the satellite (4) from the hardware adaptation layer HAL (10). These parameters define the position of the satellite and of its beams and allow the timing of arrival of data bursts from the mobile access node to satellite access node to be predicted. An independent claim is also included for a wireless link signal comprising a data burst including in temporal sequence, a method of receiving signal over a wireless link.
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Patent Agency Ranking
公开(公告)号：DE69738644D1
公开(公告)日：2008-05-29
申请号：DE69738644
申请日：1997-12-04
Applicant: INMARSAT LTD
Inventor： HARPER JOHN ANTHONY , MACRIDIS PHILIP
IPC: H04B7/26 , H04J3/00 , H04B7/185 , H04B7/212 , H04J3/16 , H04L12/70 , H04Q11/04 , H04W4/00 , H04W16/28 , H04W28/20 , H04W60/00 , H04W72/04 , H04W74/04 , H04W76/02 , H04W76/06 , H04W84/06 , H04W99/00
Abstract: A satellite communications system provides a communications service to a mobile terminal (2) on which different communications applications (4a to 4d) may be run. Calls are set up between any of the applications (4a to 4d) via a satellite (12) to a network management centre (18) which provides different service adaptors (20a to 20d) which adapt the calls to different types of service provided over terrestrial networks (22), such as telephony, facsimile, internet or ATM services. The bandwidth allocated to each call over the satellite link may be varied during the call according to demand either from the relevant application (4) or from the network management centre (18). Multiple calls may be connected concurrently to or from different applications running on the mobile terminal. A maximum bandwidth is allocated to each call. Efficient use is thereby made of the limited bandwidth available over the satellite (12), according to the instantaneous bandwidth requirements of different applications (4). For real-time calls requiring multiple slots per frame in a TDMA channel, the slots are mutually spaced apart to reduce delay.
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公开(公告)号：NO20060211L
公开(公告)日：2006-03-09
申请号：NO20060211
申请日：2006-01-13
Applicant: INMARSAT LTD
Inventor： GRANT ALEXANDER
Abstract: In a multi-user detection receiver, a multi-user detector DET receives a signal from a multiple access channel MA and the current soft estimates of each user's contribution to the received signal, and outputs updated soft estimates for each user by subtracting the current soft estimates of all the interfering users. The updated soft estimate or soft demodulated by soft demodulators DEM 1 . . . DEM K , the coded by soft decoders DEC 1 . . . DEC K which refine the probabilities of the coded bits derived from the soft demodulators DEM 1 . . . DEM K , by taking into account the knowledge of the code, and output to soft modulators M 1 . . . M K . For each iteration of the MUD receiver algorithm, an acquisition function ACQ acquires the timing of the estimates of each user's contribution to the channel for use by the detector DET in the next iteration, giving improved acquisition performance over conventional single-user techniques.
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公开(公告)号：DE60104144T2
公开(公告)日：2005-07-28
申请号：DE60104144
申请日：2001-12-14
Applicant: INMARSAT LTD
Inventor： TRACHTMAN EYAL
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公开(公告)号：CA2553271A1
公开(公告)日：2005-07-28
申请号：CA2553271
申请日：2004-01-16
Applicant: INMARSAT LTD
Inventor： DRAKOS EVRIPIDES
Abstract: A multibeam is configured to transmit a duplicate of a channel from one spot beam in another spot beam, which contains a remote monitoring station. The satellite is reconfigurable to select the channel which is duplicated, allowing the beams of the satellite to be monitored, without the need for a remote monitoring station in each beam.
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公开(公告)号：AU2004313310A1
公开(公告)日：2005-07-28
申请号：AU2004313310
申请日：2004-01-16
Applicant: INMARSAT LTD
Inventor： DRAKOS EVRIPIDES
Abstract: A multibeam is configured to transmit a duplicate of a channel from one spot beam in another spot beam, which contains a remote monitoring station. The satellite is reconfigurable to select the channel which is duplicated, allowing the beams of the satellite to be monitored, without the need for a remote monitoring station in each beam.
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