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US6141335A Expired / Lapsed US ⏱️ 0.0 years remaining

Radio communication system

Assignee: Hitachi Ltd
•
Filing: 1997-12-04
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Granted: 2000-10-31
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Expires: 2017-12-04
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Abstract

Abstract In a cellular radio communication system including a plurality of base stations and a plurality of terminals in which one cell is divided into a plurality of sectors, each of the base stations transmits and receives control information by an omnidirectional beam and transmits and receives traffic information by a directional beam. Alternatively, each of the base stations transmits and receives control information by a directional beam with a time difference of the same control information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam.

Inventors

  • 👤 Mikio Kuwahara
  • 👤 Seishi Hanaoka
  • 👤 Nobukazu Doi
  • 👤 Takaki Uta

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 16:22
CPC Classifications
H; H04; H04W; H04W16/00; H04W16/24; H04W16/28; H01; H01Q; H01Q1/00; H01Q1/12; H01Q1/22; H01Q1/24; H01Q1/241; H01Q1/246; H01Q25/00; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/06; H04B7/0686; H04B7/0695; H04B7/06952; H04B7/08; H04B7/0868; H04B7/088; H04W36/00; H04W36/24; H04W36/30; Y; Y02; Y02D; Y02D30/00; Y02D30/70

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 226 words
A cellular radio communication system comprising a plurality of base stations and a plurality of terminals and in which one cell is divided into a plurality of sectors, wherein each of said plurality of base stations transmits and receives control information by a directional beam with a time difference of the same information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam, wherein said directional beam for said control information is transmitted in such a manner that it is rotated when said base station is seen from above, and wherein channels are multiplexed by a CDMA system, wherein said CDMA system shall be in accordance with the TIA/EIA/IS-95-A and said control information are a pilot signal, call connection information, broadcast information and paging information, and wherein a plurality of base stations which are located close to each other transmit pilot signals with a synchronization of transmission angles of said pilot signals, wherein said plurality of base stations which are located close to each other are ranked according to signal phase order, each said base station receives the adjacent pilot signal of higher order signal phase and transmits a pilot signal in the direction opposite to the direction from which said pilot signal is received, thereby synchronizing transmission angles of pilot signals of a plurality of base stations.
Claim 2
Dependent Claim 226 words
A cellular radio communication system comprising a plurality of base stations and a plurality of terminals and in which one cell is divided into a plurality of sectors, wherein each of said plurality of base stations transmits and receives control information by a directional beam with a time difference of the same information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam, wherein said directional beam for said control information is transmitted in such a manner that it is rotated when said base station is seen from above, and wherein channels are multiplexed by a CDMA system, wherein said CDMA system shall be in accordance with the TIA/EIA/IS-95-A and said control information are a pilot signal, call connection information, broadcast information and paging information, and wherein a plurality of base stations which are located close to each other transmit pilot signals with a synchronization of transmission angles of said pilot signals, wherein said plurality of base stations which are located close to each other are ranked according to signal phase order, each said base station receives the adjacent pilot signal of higher order signal phase and transmits a pilot signal in the direction opposite to the direction from which said pilot signal is received, thereby synchronizing transmission angles of pilot signals of a plurality of base stations.
Claim 3
Dependent Claim 232 words
A cellular radio communication system comprising a plurality of base stations and a plurality of terminals and in which one cell is divided into a plurality of sectors, wherein each of said plurality of base stations transmits and receives control information by a directional beam with a time difference of the same information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam, wherein said directional beam for said control information is transmitted in such a manner that it is rotated when said base station is seen from above, and wherein channels are multiplexed by a CDMA system, wherein said CDMA system shall be in accordance with the TIA/EIA/IS-95-A and said control information are a pilot signal, call connection information, broadcast information and paging information, and wherein a plurality of base stations which are located close to each other transmit pilot signals with a synchronization of transmission angles of said pilot signals, wherein each terminal includes more than two receivers, searches cells of other base station than a present communicated base station, memorizes and reports an arrival time and a cycle of a pilot signal from other base station than said presently communicated base station to said presently communicated base station and said presently communicated base station controls a transmit power in accordance with said arrival time and said cycle of said pilot signal.
Claim 4
Dependent Claim 232 words
A cellular radio communication system comprising a plurality of base stations and a plurality of terminals and in which one cell is divided into a plurality of sectors, wherein each of said plurality of base stations transmits and receives control information by a directional beam with a time difference of the same information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam, wherein said directional beam for said control information is transmitted in such a manner that it is rotated when said base station is seen from above, and wherein channels are multiplexed by a CDMA system, wherein said CDMA system shall be in accordance with the TIA/EIA/IS-95-A and said control information are a pilot signal, call connection information, broadcast information and paging information, and wherein a plurality of base stations which are located close to each other transmit pilot signals with a synchronization of transmission angles of said pilot signals, wherein each terminal includes more than two receivers, searches cells of other base station than a present communicated base station, memorizes and reports an arrival time and a cycle of a pilot signal from other base station than said presently communicated base station to said presently communicated base station and said presently communicated base station controls a transmit power in accordance with said arrival time and said cycle of said pilot signal.
Claim 5
Dependent Claim 236 words
A cellular radio communication system comprising a plurality of base stations and a plurality of terminals and in which one cell is divided into a plurality of sectors, wherein each of said plurality of base stations transmits and receives control information by a directional beam with a time difference of the same information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam, wherein said directional beam for said control information is transmitted in such a manner that it is rotated when said base station is seen from above, and wherein channels are multiplexed by a CDMA system, wherein said CDMA system shall be in accordance with the TIA/EIA/IS-95-A and said control information are a pilot signal, call connection information, broadcast information and paging information, and wherein a plurality of base stations which are located close to each other transmit pilot signals with a synchronization of transmission angles of said pilot signals, wherein each terminal includes more than two receivers, searches cells of other base station than a presently communicated base station, memorizes and reports a phase difference between a pilot signal of said presently communicated base station and a pilot signal of said base station other than said presently communicated base station to said presently communicated base station, and said presently communicated base station does not transmit traffic information during a time corresponding to said phase difference.
Claim 6
Dependent Claim 236 words
A cellular radio communication system comprising a plurality of base stations and a plurality of terminals and in which one cell is divided into a plurality of sectors, wherein each of said plurality of base stations transmits and receives control information by a directional beam with a time difference of the same information in a plurality of sectors within one cell and transmits and receives traffic information by a directional beam, wherein said directional beam for said control information is transmitted in such a manner that it is rotated when said base station is seen from above, and wherein channels are multiplexed by a CDMA system, wherein said CDMA system shall be in accordance with the TIA/EIA/IS-95-A and said control information are a pilot signal, call connection information, broadcast information and paging information, and wherein a plurality of base stations which are located close to each other transmit pilot signals with a synchronization of transmission angles of said pilot signals, wherein each terminal includes more than two receivers, searches cells of other base station than a presently communicated base station, memorizes and reports a phase difference between a pilot signal of said presently communicated base station and a pilot signal of said base station other than said presently communicated base station to said presently communicated base station, and said presently communicated base station does not transmit traffic information during a time corresponding to said phase difference.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-10-31 2004-05-01 2004-10-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-10-31 2008-05-01 2008-10-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-10-31 2012-05-01 2012-10-31 $7700.00 Window Closed / Lapsed

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