公开(公告)号：EP0760561A3

公开(公告)日：1998-05-13

申请号：EP96113034

申请日：1996-08-13

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  MILLER NIGEL ,  TAILOR BHARAT ,  ALI KAMAL ,  BEAUCHAMP GARY ,  LAM SIMON ,  LAZARIS-BRUNNER KEN

IPC: H04B7/204

CPC classification number: H04B7/2041

Abstract: A repeater for a multibeam communications satellite combines the features of coaxial channel interbeam switching and subchannelization of some of the channels. In one embodiment described, the input radio-frequency signals from the input beams are fed through the input multiplexers to form channels. Some, but not all, channels are subsequently subchannelized for interbeam switching. In another embodiment of the invention, a portion of the incoming radio frequency signals bypasses the input demultiplexer and is filtered for noise-limiting reasons, converted down to an intermediate frequency and then subchannelized using SAW filters. The specification also teaches that digital techniques can be used to obtain the same results. Especially in the case of satellites with a large number of beams and a large number of channels, it is not necessary to have full interbeam switching of all the subchannels derived from one channel: instead, the specification proposes the use of parallel configurations of smaller, less complex switching networks.

公开(公告)号：EP0780998A3

公开(公告)日：1998-09-16

申请号：EP96119806

申请日：1996-12-10

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  BEAUCHAMP GARY ,  O'DONOVAN VAL

IPC: H04B7/185

CPC classification number: H04B7/18521

Abstract: This invention concerns improvements in the efficiency and flexibility of multi-beam communications satellites connected by intersatellite links. It will increase the number of customers serviced and hence the revenue generated when intersatellite links are employed by multibeam satellites which use the currently available technology in a bent-pipe microwave architecture.
Existing multibeam systems use the bent-pipe microwave architecture. Information from one geographic region uplinked to one satellite can be transferred to a second satellite via intersatellite link and then downlinked into a second geographic region. These multibeam systems waste available bandwidth capacity by tying up complete intersatellite link transponders even if the channels are not full because information switching is conducted at a full transponder level. Further, if information is broadcast, as in news-gathering applications, to several downlink beams, the system ties up, in the receiving satellite, one transponder per downlink beam.
In future systems using on-board digital-processing technology, it is theoretically possible that information can be switched at a much finer bandwidth level. Hence, one intersatellite channel could handle traffic originating from several uplink beams on the first satellite with destinations to several downlink beams on the second satellite which avoids the inefficiency of a partially full transponder. However, customer terminals have to be designed for the modulation and coding architecture specific to that system and cannot be used with any other system.
The present invention solves spectral flexibility and inefficiency problems of existing systems, and is transparent to all modulation and coding architectures while still allowing for communication with all terminals currently in use with communications satellites. The approach used is to combine switching at a subchannel level (solving flexibility and inefficiency problems) while using technologies compatible with bent-pipe architecture (solving terminal-compatibility problems) with an intersatellite link. Technologies used include Surface Acoustic Wave (SAW) filtering and solid-state switching.
This invention will provide spectral efficiency and flexibility approaching but not equalling the theoretical efficiency and flexibility of future systems employing digital signal processing. It will, however, be significantly more efficient than future digital satellite systems in terms of the two most expensive satellite resources, power and mass.

公开(公告)号：DE60034121T2

公开(公告)日：2007-11-08

申请号：DE60034121

申请日：2000-02-01

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  SVENSSON NICHOLAS ,  VO THAI

IPC: G01R27/32 ,  G01R27/28 ,  G01R35/00

Abstract: A system and method of calibrating an S parameter measurement instrument (such as a vector network analyzer) in which the number of calibrations required to fully characterize the error model of an n-port system is n/2 calibrations for an even number of ports and (n+1)/2 calibrations for an odd number of ports. Each test port in the system is involved in at least one full calibration, thus n/2 test paths are fully calibrated. For each measured test path, the error terms of the applicable error model are calculated. These error terms are then decoupled from the associated test path into error parameters that are localized to the individual test ports of the test path. Having localized the error parameters, the error model for each test port can then be treated independently from the other test ports. The error terms for the test paths that are not calibrated are then constructed using the localized error parameters for the individual test ports.

公开(公告)号：DE69626905D1

公开(公告)日：2003-04-30

申请号：DE69626905

申请日：1996-08-13

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  MILLER NIGEL ,  TAILOR BHARAT ,  ALI KAMAL ,  BEAUCHAMP GARY ,  LAM SIMON ,  LAZARIS-BRUNNER KEN

IPC: H04B7/204

公开(公告)号：CA2165875C

公开(公告)日：2001-03-13

申请号：CA2165875

申请日：1995-12-21

Applicant: COM DEV LTD

Inventor： O'DONOVAN VAL ,  PEACH ROBERT ,  BEAUCHAMP GARY

IPC: H04B7/185

Abstract: A multibeam communications satellite has direct links with at least one othe r satellite. The satellite's repeater operates in the bent-pipe mode and can provide serv ice to users independent of signal content, format and protocol. Each incoming electromag netic (radio) beam received by the satellite contains at least one channel of info rmation, and each channel is divisible into subchannels. Naturally, each subchannel is of a bandwidth which is less than the bandwidth of the channel from which the subchannel wa s derived. The other satellite has outgoing beams that complement the first satellites incoming beams. Generally, both satellites have processors on board designed to inter beam-switch at the subchannel level. (However, a description is given also of an instanc e where one or the other satellites may not have subchannelizing capability and limited use may be made of the invention). The satellites are linked by an intersatellite link carrying information on a channel consisting of subchannels constituted from several incoming channels. Therefore, an outgoing beam from the second satellite can contain a channel having information combined from several incoming channels to the first sate llite and the channel information on any incoming electromagnetic (radio) beam can be deli vered at the subchannel level to several output beams from the second satellite. The system can operate in a broadcast mode whereby information at the subchannel level can be distributed simultaneously (i.e. in parallel) to several outgoing electromag netic (radio) beams. The intersatellite link is treated as any other beam (incoming or out going, as the case may be), although its operating wavelength may be different from the op erating wavelengths of the beams having terrestrial origin or destination. For examp le, the intersatellite link could be at microwave, optical or some other suitable fr equency. The basic concept may be extended to a system supporting multiple intersatellite links, e.g. links in both directions between the two satellites or, in some circumstance s, among a constellation of more than two satellites.

公开(公告)号：NO963548L

公开(公告)日：1997-03-03

申请号：NO963548

申请日：1996-08-26

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  MILLER NIGEL ,  TAILOR BHARAT ,  ALI KAMAL ,  BEAUCHAMP GARY ,  LAM SIMON ,  LAZARIS-BRUNNER KEN

IPC: H04B7/204 ,  H04B7/185

公开(公告)号：DE60034121D1

公开(公告)日：2007-05-10

申请号：DE60034121

申请日：2000-02-01

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  SVENSSON NICHOLAS ,  VO THAI

IPC: G01R27/32 ,  G01R27/28 ,  G01R35/00

Abstract: A system and method of calibrating an S parameter measurement instrument (such as a vector network analyzer) in which the number of calibrations required to fully characterize the error model of an n-port system is n/2 calibrations for an even number of ports and (n+1)/2 calibrations for an odd number of ports. Each test port in the system is involved in at least one full calibration, thus n/2 test paths are fully calibrated. For each measured test path, the error terms of the applicable error model are calculated. These error terms are then decoupled from the associated test path into error parameters that are localized to the individual test ports of the test path. Having localized the error parameters, the error model for each test port can then be treated independently from the other test ports. The error terms for the test paths that are not calibrated are then constructed using the localized error parameters for the individual test ports.

公开(公告)号：CA2361666C

公开(公告)日：2005-11-01

申请号：CA2361666

申请日：2000-02-01

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  VO THAI ,  SVENSSON NICHOLAS

IPC: G01R27/28 ,  G01R35/00 ,  G01R23/00

Abstract: A system and method of calibrating an S parameter measurement instrument (such as a vector network analyzer) in which the number of calibrations required to fully characterize the error model of an n-port system is n/2 calibrations for an even number of ports and (n+1)/2 calibrations for an odd number of ports. Each test port in the system is involved in at least one full calibration, thus n/2 test paths are fully calibrated. For each measured test path, the error terms of the applicable error model are calculated. These error teens are then decoupled from the associated test path into error parameters that are localized to the individual test ports of the test path. Having localized the error parameters, the error model for each test port can then be treated independently from the other test ports. The error terms for the test paths that are not calibrated are then constructed using the localized error parameters for the individual test ports.

公开(公告)号：DE69627284D1

公开(公告)日：2003-05-15

申请号：DE69627284

申请日：1996-12-10

Applicant: COM DEV LTD

Inventor： PEACH ROBERT ,  BEAUCHAMP GARY ,  O'DONOVAN VAL

IPC: H04B7/185

公开(公告)号：CA2361666A1

公开(公告)日：2000-08-10

申请号：CA2361666

申请日：2000-02-01

Applicant: COM DEV LTD

Inventor： VO THAI ,  SVENSSON NICHOLAS ,  PEACH ROBERT

IPC: G01R27/28 ,  G01R35/00 ,  G01R23/00

Abstract: A system and method of calibrating an S parameter measurement instrument (su ch as a vector network analyzer) in which the number of calibrations required t o fully characterize the error model of an n-port system is n/2 calibrations f or an even number of ports and (n+1)/2 calibrations for an odd number of ports. Each test port in the system is involved in at least one full calibration, thus n/2 test paths are fully calibrated. For each measured test path, the error terms of the applicable error model are calculated. These error terms are then decoupled from the associated test path into error parameters that are localized to the individual test ports of the test path. Having localize d the error parameters, the error model for each test port can then be treated independently from the other test ports. The error terms for the test paths that are not calibrated are then constructed using the localized error parameters for the individual test ports.