公开(公告)号：JP2004135299A

公开(公告)日：2004-04-30

申请号：JP2003296498

申请日：2003-08-20

Applicant: Internatl Business Mach Corp ,  インターナショナル・ビジネス・マシーンズ・コーポレーションInternational Business Maschines Corporation

Inventor： AHMADI HAMID ,  BAUCHOT FREDERIC J ,  BONNET ROSELYNE ,  KESSLER ILAN ,  KRISHNA ARVIND ,  LANNE FABIEN P ,  NAGHSHINEH MAHMOUD ,  SOLAR CATHERINE ,  WETTERWALD MICHELLE M

IPC: G06F13/00 ,  H04B7/26 ,  H04L12/56 ,  H04L29/06 ,  H04L29/12 ,  H04W8/26 ,  H04W40/24 ,  H04W40/26 ,  H04W40/36 ,  H04W80/04 ,  H04W92/02

CPC classification number: H04W92/02 ,  H04L29/12009 ,  H04L45/02 ,  H04L61/00 ,  H04W8/26 ,  H04W40/248 ,  H04W40/26 ,  H04W40/36 ,  H04W80/04

Abstract: PROBLEM TO BE SOLVED: To provide a system for maintaining routing information based on a unique address to efficiently communicate when a moving object moves between domains.
SOLUTION: A communication network having a number of routers, a number of base stations and a number of moving objects allocates the unique address which is known by a routing entity of the network to each moving object to maintain a communication with the moving object. The unique address of the moving object is contained in topology updating of the network, such that all routers can know the location of the moving object anytime. Namely, the moving object moves into a domain of a new access point, establishes a new link with the new access point and then notifies all the routers of its new location using a topology updating mechanism of the network. Each of the routers of the network updates its routing table to be routed within a path including the new access point.
COPYRIGHT: (C)2004,JPO

公开(公告)号：DE69431219D1

公开(公告)日：2002-10-02

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

IPC: H04B7/08 ,  H04L1/02

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.

公开(公告)号：CA2115211C

公开(公告)日：1997-09-23

申请号：CA2115211

申请日：1994-02-08

Applicant: IBM

Inventor： BANTZ DAVID F ,  LAMAIRE RICHARD O ,  KRISHNA ARVIND ,  NATARAJAN KADATHUR S ,  BAUCHOT FREDERIC J ,  AHMADI HAMID

IPC: H04J3/00 ,  H04B7/24 ,  H04J3/16 ,  H04L12/28 ,  H04L12/56

Abstract: A Medium Access (MAC) Protocol is utilized for wireless radio access for a plurality of remote stations to a base station on a LAN. The MAC protocol is based on a reservation scheme for user data traffic and a random access technique for control and signalling traffic. There is a time division fixed frame structure in which time is slotted, and time slots are grouped into fixed frames consisting of data and control subframes or periods. The fixed frame structure consists of three periods (A, B, and C) along with their respective headers. The first period, the A period, is the outbound channel which is used exclusively for data transfer from the base station to the remote stations. The following period, the B period, is the inbound channel that is used for contention-free data transfer from the remote stations to the base station. The allocation of the data slots in the A and B periods is performed by the base station. The last period of the frame, designated as the C period, is the control channel used for the transmission of reservation requests and data from the remote stations to the base station in a random-access contention mode using a slotted Aloha protocol. The duration of the three periods may be varied using a movable boundary technique. The base station estimates the number of actively transmitting remote stations utilizing feedback information from the remote stations. This estimate is broadcast to the remote stations as control indicia to control their transmission attempts in the C period, thus yielding high transmission efficiency.

公开(公告)号：CA2113734A1

公开(公告)日：1994-10-31

申请号：CA2113734

申请日：1994-01-19

Applicant: IBM

Inventor： BANTZ DAVID F ,  BAUCHOT FREDERIC J ,  HUANG CHIA-CHI ,  MOULTON NICHOLAS

IPC: H04B7/08 ,  H04L1/02 ,  H04B7/26 ,  H04B7/04

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.

公开(公告)号：CA2142794C

公开(公告)日：2001-03-13

申请号：CA2142794

申请日：1995-02-17

Applicant: IBM

Inventor： ANTUNES ERNESTO ,  BANTZ DAVID F ,  BAUCHOT FREDERIC J ,  DAL BELLO ELIANE ,  FERRAZ MARCELO ,  LEMAUT FRANCOIS ,  TAVARES BERNARDO DA SILVA A

IPC: G06F15/16 ,  G06F1/14 ,  G06F9/52 ,  G06F15/177 ,  H04B1/7156 ,  H04B7/26 ,  H04L12/28 ,  H04L7/04 ,  H04B1/713

Abstract: A wireless Local Area Network (LAN), in which each wireless adapter includes a controller and a transceiver which arc located a finite distance from each other. Each controller and transceiver has their own hop clock and hop table. A data interface which includes a command set is defined between the controller and the transceiver. The comma nd set includes commands and procedures for synchronizing the hop clocks and hop tables between the controller and the transceiver.

公开(公告)号：CA2145165A1

公开(公告)日：1995-10-13

申请号：CA2145165

申请日：1995-03-20

Applicant: IBM

Inventor： HUANG CHIA-CHI ,  BANTZ DAVID F ,  BAUCHOT FREDERIC J ,  NATARAJAN KADATHUR S ,  NARASIMHAN ANAND ,  WETTERWALD MICHELE M

IPC: G06F13/00 ,  H04L12/28 ,  H04W24/00 ,  H04W36/08 ,  H04W36/30 ,  H04W84/12 ,  H04Q7/38

Abstract: Methods for handoff in a wireless communication network comprised of a local area 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 more of said mobile stations under control of a controller, with communication between base stations and mobile stations being performed by frequency hopping, with there being n available frequency hopping channels in a fixed frequency band, with each channel being of a same fixed 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 performance 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 transferring control of said mobile station to said another base station in response to the sensed transmission.

公开(公告)号：CA2142794A1

公开(公告)日：1995-09-19

申请号：CA2142794

申请日：1995-02-17

Applicant: IBM

Inventor： ANTUNES ERNESTO ,  BANTZ DAVID F ,  BAUCHOT FREDERIC J ,  DELBELLO ELIANE D ,  FERRAZ MARCELO ,  LEMAUT FRANCOIS ,  TAVARES BERNARDO DA SILVA A

IPC: G06F15/16 ,  G06F1/14 ,  G06F9/52 ,  G06F15/177 ,  H04B1/7156 ,  H04B7/26 ,  H04L12/28 ,  H04L7/04 ,  H04B1/713

Abstract: A wireless Local Area Network (LAN), in which each wireless adapter includes a controller and a transceiver which arc located a finite distance from each other. Each controller and transceiver has their own hop clock and hop table. A data interface which includes a command set is defined between the controller and the transceiver. The comma nd set includes commands and procedures for synchronizing the hop clocks and hop tables between the controller and the transceiver.

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

IPC: H04B7/08 ,  H04L1/02

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.

公开(公告)号：PL179066B1

公开(公告)日：2000-07-31

申请号：PL32175496

申请日：1996-01-16

Applicant: IBM

Inventor： AHMADI HAMID ,  BAUCHOT FREDERIC J ,  BONNET ROSELYNE ,  KESSLER ILAN ,  KRISHNA ARVIND ,  LANNE FABIEN P ,  NAGHSHINEH MAHMOUD ,  SOLER CATHERINE ,  WETTERWALD MICHELLE MARIE

IPC: H04B7/26 ,  H04L12/56 ,  H04L29/06 ,  H04L29/12 ,  H04W8/26 ,  G06F13/00 ,  H04W40/24 ,  H04W40/26 ,  H04W40/36 ,  H04W80/04 ,  H04W92/02 ,  H04Q7/20 ,  H04Q7/24

Abstract: A communications network having a number of routers, a number of base stations and a number of mobile units maintains communications with the mobile units by assigning a unique address known to the routing entities of the network to each mobile unit. By including the mobile units unique address in topology updates of the network, the location of the mobile unit at any time is made known to all routers of the network. That is, once a mobile unit moves into a domain of a new access point and establishes a new link with the new access point, it uses the topology update mechanism of the network to make its new location known to all routers. Once a router of the network receives topology update information specific to the mobile unit's new location, it updates its routing table such that packets destined to the mobile unit are routed in a path which terminates at the mobile unit and contains its new access point.

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

IPC: H04B1/7156 ,  H04J13/00 ,  H04L7/04 ,  H04Q7/38 ,  H04B7/12 ,  H04B1/713 ,  H04Q7/22

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.