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公开(公告)号:DE69429759T2
公开(公告)日:2002-09-12
申请号:DE69429759
申请日:1994-09-23
Applicant: IBM
Inventor: BAUCHOT FREDERICK J , HUANG CHIA-CHI , KESSLER ILAN , NATARAJAN KADATHUR S
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公开(公告)号:ES2177552T3
公开(公告)日:2002-12-16
申请号:ES94105877
申请日:1994-04-15
Applicant: IBM
Inventor: BANTZ DAVID F , BAUCHOT FREDERIC J , HUANG CHIA-CHI , MOULTON NICHOLAS J A
Abstract: In a mobile cellular communication system, a base station is wired to a Local Area Network (LAN), and has wireless communication with a plurality of mobile stations. Multipath fading is substantially reduced in the system by utilizing antenna diversity techniques at the base station and each of the plurality of mobile stations. The combination of the independent operation of antenna selection diversity at both a base station and a mobile station results in the selection of the best propagation path between the two stations.
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公开(公告)号:DE69230513T2
公开(公告)日:2000-07-06
申请号:DE69230513
申请日:1992-06-03
Applicant: IBM
Inventor: BANTZ DAVID FREDERICK , CATO ROBERT THOMAS , HUANG CHIA-CHI
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公开(公告)号:DE69228156T2
公开(公告)日:1999-08-05
申请号:DE69228156
申请日:1992-07-11
Applicant: IBM
Inventor: NATARAJAN KADATHUR SUBRAMANYA , HUANG CHIA-CHI
Abstract: A method and apparatus for conserving battery power in a wireless link adapter of a battery operated computer such as a portable laptop computer, as controlled by a scheduled multiaccess protocol. The portable computer is operable as a mobile unit in a multi-cell wireless network. The scheduled access multiaccess protocol is implemented to effectively conserve battery power by suitable control of the state of the controller, the transmitter and receiver units at the wireless link adapter by scheduling when the adapter is in a normal running mode, or a standby mode in which power is conserved.
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公开(公告)号:CA2132765C
公开(公告)日:1999-01-05
申请号:CA2132765
申请日:1994-09-23
Applicant: IBM
Inventor: BAUCHOT FREDERIC J , HUANG CHIA-CHI , KESSLER ILAN , NATARAJAN KADATHUR S
Abstract: A method for use in multicellular communication network system of the type having base stations and a plurality of remote stations. The method achieves reliable and fault tolerant synchronization between the stations in a call when a frequency hopping technique is used. The method includes steps for acquiring the frequency hop sequence by remote station and tracking the frequency hop sequence after acquisition in order to stay in synchronism. The method also provides for recovering from loss of synchronism and for staying in synchronism.
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16.
公开(公告)号:CA2114570C
公开(公告)日:1998-09-15
申请号:CA2114570
申请日:1994-01-31
Applicant: IBM
Inventor: BANTZ DAVID F , BAUCHOT FREDERICK J , HUANG CHIA-CHI , LANNE FABIEN P , NATARAJAN KADATHUR S , WETTERWALD MICHELLE M
Abstract: A control system for automated management of frequency-hopping in a radio network. The system includes a Wireless Network Manager (WNM) or Controller and a Wireless Control Agent (WCA), which control the distribution and maintenance of hopping patterns in the radio network. In a single cell network, the WNM and the WCA are included in a single base station. In a multiple cell network, the WNM is in a specific station on a LAN, and a WCA is located in each base station on the LAN. In each instance, the WNM is a centralized managing station and the WCA acts as a cell controller.
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公开(公告)号:DE69431219T2
公开(公告)日:2003-04-30
申请号:DE69431219
申请日:1994-04-15
Applicant: IBM
Inventor: BANTZ DAVID F , BAUCHOT FREDERIC J , HUANG CHIA-CHI , MOULTON NICHOLAS J A
Abstract: In a mobile cellular communication system, a base station is wired to a Local Area Network (LAN), and has wireless communication with a plurality of mobile stations. Multipath fading is substantially reduced in the system by utilizing antenna diversity techniques at the base station and each of the plurality of mobile stations. The combination of the independent operation of antenna selection diversity at both a base station and a mobile station results in the selection of the best propagation path between the two stations.
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公开(公告)号:AT223123T
公开(公告)日:2002-09-15
申请号:AT94105877
申请日:1994-04-15
Applicant: IBM
Inventor: BANTZ DAVID F , BAUCHOT FREDERIC J , HUANG CHIA-CHI , MOULTON NICHOLAS J A
Abstract: In a mobile cellular communication system, a base station is wired to a Local Area Network (LAN), and has wireless communication with a plurality of mobile stations. Multipath fading is substantially reduced in the system by utilizing antenna diversity techniques at the base station and each of the plurality of mobile stations. The combination of the independent operation of antenna selection diversity at both a base station and a mobile station results in the selection of the best propagation path between the two stations.
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公开(公告)号:CA2145165C
公开(公告)日:1999-03-02
申请号:CA2145165
申请日:1995-03-20
Applicant: IBM
Inventor: HUANG CHIA-CHI , BANTZ DAVID F , NARASIMHAN ANAND , WETTERWALD MICHELE M , BAUCHOT FREDERIC J , NATARAJAN KADATHUR S
Abstract: Methods for handoff in a wireless communication network comprised of a local are a network connected to a plurality of base stations, each of which has a geographic area, defined as a cell, within which mobile stations can communicate with a base station, with each such base station being capable of performing bidirectional wireless communication with one or mor e of said mobile stations under control of a controller, with communication between base s tations and mobile stations being performed by frequency hopping, with there being n availab le frequency hopping channels in a fixed frequency band, with each channel being of a same fi xed duration and having a fixed frequency different than another channel. The handoff method employs structure and techniques for determining by a mobile station that the quality of transmission between it and a current base station has degraded below a predetermined perform ance level, structure and technique for said mobile station to listen to each of successive frequency channels for a duration substantially less than said fixed duration of a channel until it senses a transmission from another base station, and structure and techniques for transfe rring control of said mobile station to said another base station in response to the sensed trans mission.
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公开(公告)号:CA2132765A1
公开(公告)日:1995-04-23
申请号:CA2132765
申请日:1994-09-23
Applicant: IBM
Inventor: BAUCHOT FREDERIC J , HUANG CHIA-CHI , KESSLER ILAN , NATARAJAN KADATHUR S
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