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公开(公告)号：DE69433872T2
公开(公告)日：2005-07-14
申请号：DE69433872
申请日：1994-10-26
Applicant: IBM
Abstract: A Medium Access (MAC) Protocol is utilized for wireless access, preferrably over a radio frequency channel, 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 frame structure in which time is slotted. Time slots are grouped into variable length periods. The variable frame structure consists of a frame header followed by interleaved periods of different types (type A, B or C). Type A periods are allocated to the outbound channel which is used for data transfer from the base station to the remote stations. Type B periods, are allocated to the inbound channel that is used for contention-free data transfer from the remote stations to the base station. Allocation of the data slots in the A and B periods is performed by the base station. Type C periods are reserved to the control channel used for 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 and sequence of periods may be varied by using a technique for interleaving periods of different types. 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 C slots, thus yielding high transmission efficiency.
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12.发明专利
公开(公告)号：HU221581B
公开(公告)日：2002-11-28
申请号：HU9802235
申请日：1996-01-16
Applicant: IBM
Inventor： AHMADI HAMID , BAUCHOT FREDERIC JACQUES , BONNET ROSELYNE , KESSLER ILAN , KRISHNA ARVIND , LANNE FABIEN P , NAGHSHINEH MAHMOUD , SOLER CATHERINE , WETTERWALD MICHELLE MARIE
IPC: H04B7/26 , G06F13/00 , H04L12/56 , H04L29/06 , H04L29/12 , H04W8/26 , H04W40/24 , H04W40/26 , H04W40/36 , H04W80/04 , H04W92/02 , 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.
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公开(公告)号：ES2154652T3
公开(公告)日：2001-04-16
申请号：ES94105696
申请日：1994-04-13
Applicant: IBM
Inventor： AHMADI HAMID , BANTZ DAVID FREDERICK , BAUCHOT FREDERIC JACQUES , KRISHNA ARVIND , LA MAIRE RICHARD ORVILLE , NATARAJAN KADATHUR S
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.
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Patent Agency Ranking
公开(公告)号：BR9401624A
公开(公告)日：1994-11-22
申请号：BR9401624
申请日：1994-04-27
Applicant: IBM
Inventor： BANTZ DAVID FREDERICK , BAUCHOT FREDERIC JACQUES , HUANG CHIA-CHI , WAY NICHOLAS JOHN ANDREW
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：DE69433872D1
公开(公告)日：2004-08-05
申请号：DE69433872
申请日：1994-10-26
Applicant: IBM
Abstract: A Medium Access (MAC) Protocol is utilized for wireless access, preferrably over a radio frequency channel, 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 frame structure in which time is slotted. Time slots are grouped into variable length periods. The variable frame structure consists of a frame header followed by interleaved periods of different types (type A, B or C). Type A periods are allocated to the outbound channel which is used for data transfer from the base station to the remote stations. Type B periods, are allocated to the inbound channel that is used for contention-free data transfer from the remote stations to the base station. Allocation of the data slots in the A and B periods is performed by the base station. Type C periods are reserved to the control channel used for 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 and sequence of periods may be varied by using a technique for interleaving periods of different types. 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 C slots, thus yielding high transmission efficiency.
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公开(公告)号：PL321754A1
公开(公告)日：1997-12-22
申请号：PL32175496
申请日：1996-01-16
Applicant: IBM
Inventor： AHMADI HAMID , BAUCHOT FREDERIC JACQUES , BONNET ROSELYNE , KESSLER ILAN , KRISHNA ARVIND , LANNE FABIEN P , NAGHSHINEH MAHMOUD , SOLER CATHERINE , WETTERWALD MICHELLE MARIE
IPC: H04B7/26 , G06F13/00 , H04L12/56 , H04L29/06 , H04L29/12 , H04W8/26 , H04W40/24 , H04W40/26 , H04W40/36 , H04W80/04 , H04W92/02 , 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.
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17.发明专利
公开(公告)号：CA2170786A1
公开(公告)日：1996-09-07
申请号：CA2170786
申请日：1996-03-01
Applicant: IBM
Inventor： AHMADI HAMID , BAUCHOT FREDERIC JACQUES , BONNET ROSELYNE , KESSLER ILAN , KRISHNA ARVIND , LANNE FABIEN P , NAGHSHINEH MAHMOUD , SOLER CATHERINE , WETTERWALD MICHELLE MARIE
IPC: G06F13/00 , H04B7/26 , H04L12/56 , H04L29/06 , H04L29/12 , H04W8/26 , H04W40/24 , H04W40/26 , H04W40/36 , H04W80/04 , H04W92/02 , H04L12/46
Abstract: A communications network having a number of routers, a number of base statio ns 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 e ach mobile unit. By including the mobile units unique address in topology update s of the network, the location of the mobile unit at any time is made known to all ro uters 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 u pdate 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 m obile 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 con tains its new access point.
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公开(公告)号：BR9401518A
公开(公告)日：1994-12-27
申请号：BR9401518
申请日：1994-04-18
Applicant: IBM
Inventor： AHMADI HAMID , BANTZ DAVID FREDERICK , BAUCHOT FREDERIC JACQUES , KRISHNA ARVIND , ORVILLE LA MAIRE RICHARD , NATARAJAN KADATHUR SUBRAMANYA
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.
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