Radio communication system using portable mobile terminal

• US 5,894,598 A
• Filed: 09/06/1996
• Issued: 04/13/1999
• Est. Priority Date: 09/06/1995
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Shoki, Hiroki
• Primary Examiner(s): LE, THANH C
• Application Number:
  US08/711,474
• Time in Patent Office: 949 Days
• Field of Search: 455/506, 455/517, 455/524, 455/62, 455/63, 455/65, 455/67.1, 455/67.3, 455/561, 455/562, 455/277.1, 455/277.2, 455/278.1
• US Class Current: 455/562.1
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 3/24 varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A radio communication system comprises a transmitting antenna for transmitting radio signals. Each radio signal is transmitted via one of a plurality of beams of different maximum radiated directions. The system also comprises a transmitting section for adding to a radio signal, transmitted via an i-th beam among the plurality of beams, beam identification information that identifies on which i-th beam of said plurality of beams said radio signal is being transmitted. The system further comprises a receiving antenna for receiving the radio signals transmitted by the plurality of beams and a receiver for selectively receiving a signal transmitted by a specific beam according to a predetermined estimation standard. Alternatively, the system may comprise a first radio station and a second radio station. The first radio station may include a transmitting antenna for transmitting signals with beam identification numbers and a receiving antenna for receiving signals from other radio stations. The second radio station may include a receiving antenna capable of receiving signals transmitted by the first transmitting antenna and a receiver for selectively receiving a signal transmitted by a specific beam according to a predetermined estimation standard. The second radio station may also include a transmitting antenna that forms a wide-angle beam to transmit the specific beam.

Claims

1. A radio communication system comprising:

a first radio station including

a single transmitting antenna for forming a plurality of beams of different maximum radiated directions, said first radio station adding to a signal, transmitted by a beam of number i among the plurality of beams, beam identification information that is capable of discriminating that said signal is transmitted by said beam of number i, and

a receiving antenna for receiving radio signals, which are transmitted from other radio stations by a wide-angle or omni-directional beam; and

a second radio station including

a receiving antenna which is capable of receiving said signals transmitted by said beams from said receiving antenna of said first radio station,

a receiver for selectively receiving, on the basis of an estimation standard, a signal of a beam of number j among specific beams formed by said transmitting antenna of said first radio station, and

a transmitting antenna for forming a wide-angle or omni-directional beam to transmit said beam of number j selectively received among the beams transmitted from said transmitting antenna of said first radio station.

2. A radio communication system according to claim 1, wherein

said first radio station receives a signal, to which information on said number j of said beam selectively received by said second radio station is added, and wherein said signal to be transmitted to said second radio station is transmitted by using said beam of number j among said plurality of beams of different maximum radiated directions.

3. The radio communication system according to claim 1:

wherein

a frequency band of radio waves transmitted by said first radio station is higher than a frequency band of received radio waves.

4. A radio communication method comprising:

receiving a radio signal from among a plurality of radio signals, the radio signal being transmitted by one or more beams to which beam identification information is added;

selecting optimum beam identification information which corresponds to the best beam from transmitting the radio signal, according to a predetermined estimation standard;

requiring a transmission of communication information included in the radio signal transmitted on the beam having the selected beam identification information; and

receiving the communication information included in the radio signal, wherein the method includes

forming a plurality of beams each having different maximum radiated directions by means of a transmitting antenna of a first radio station, and adding, to a radio signal transmitted by a beam of number i among the plurality of beams, beam identification information that is capable of discriminating that said radio signal is transmitted by said beam of number i,

receiving said radio signal transmitted by said beam from the transmitting antenna from said first radio station, by means of a receiving antenna of a second radio station,

selecting a signal of a beam of number j from specified beams of the transmitting antenna of said first radio station according to said predetermined estimation standard, by means of a receiver of said second radio station,

transmitting said beam of number j which is selectively received from the plurality of beams transmitted from said transmitting antenna of said first radio station, by a formed wide-angle or omni-directional beam, by means of a transmitting antenna of said second radio station,

receiving radio signals transmitted from other radio stations by a wide-angle or omni-directional beam, by means of a receiving antenna of said first radio station, and

acquiring communication information by receiving the communication information with the beam identification information which is transmitted through the transmitting antenna of said first radio station, by means of the receiving antenna of said second radio station.

5. The radio communication system according to claim 4, wherein

said predetermined estimation standard is intensity of a radio signal, and wherein a signal of a beam of the maximum received-signal intensity transmitted from said transmitting antenna is selected.

6. The radio communication system according to claim 4, wherein

said predetermined estimation standard is a signal-to-noise ratio (S-N ratio) of a received signal, and wherein a signal of a beam of the maximum S-N ratio transmitted from said transmitting antenna is selected.

7. The radio communication system according to claim 4, wherein

said predetermined estimation standard is said beam identification information, and wherein a signal of a beam specified by said beam identification information is selected.

8. A radio communication system comprising:

a first radio station including

a transmitting antenna for forming a plurality of beams of different maximum radiated directions, said first radio station adding to a signal transmitted by a beam of number i among the plurality of beams, beam identification information that is capable of discriminating that said signal is transmitted by said beam of number i, and

a receiving antenna for receiving radio signals, which are transmitted from other radio stations by a wide-angle or omni-directional beam; and

a second radio station including

a receiving antenna which is capable of receiving said signals transmitted by said beams from said transmitting antenna of said first radio station,

a receiver for selectively receiving, on the basis of an estimation standard, a signal of a beam of number j among specific beams formed by said transmitting antenna of said first radio station, and

a transmitting antenna for forming a wide-angle omni-directional beam to transmit said beam of number j selectively received among said beams transmitted from said transmitting antenna of said first radio station;

wherein said second radio station uses at least one of a narrow-angle or unidirectional beam in transmitting and receiving communication information, together with said wide-angle or omni-directional beam.