Wide area radio communication system and method for communicating in a wide area through a wide area radio communication system

• US 5,666,653 A
• Filed: 07/01/1996
• Issued: 09/09/1997
• Est. Priority Date: 08/07/1990
• Status: Expired due to Fees

• Current Assignee: Inventahl AB
• Original Assignee: Inventahl AB
• Inventors: Ahl, Karl-Axel
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): SOBUTKA, PHILIP
• Application Number:
  US08/674,195
• Time in Patent Office: 435 Days
• Field of Search: 455/33.1, 455/33.2, 455/33.3, 455/33.4, 455/53.1, 455/54.1, 455/54.2, 455/56.1, 455/12.1, 455/8, 379/58, 379/59, 375/200, 375/205, 370/95.3
• US Class Current: 370/330
• CPC Class Codes: H04W 16/28 using beam steering

Abstract

Wide area radio system comprising at least two central stations capable of maintaining communication to several peripheral stations within overlapping or adjacent service areas (110). Each central station is divided into a high frequency unit (992) and a low frequency function (991) operatively connected to said high frequency unit. Traffic interaction and coordination between said central stations in said radio system is provided through said low frequency functions (991) of said stations.

Claims

1. A method for communicating in a wide area through a wide area radio communication system, said system comprising at least two central stations receiving and transmitting user information and control information as digital signals, each of said central stations being associated with at least one peripheral station and covering a service area which at least in part is common to said two central stations, said central stations and said peripheral stations comprising transmission timing means, the method comprising the steps of:

connecting operatively at least one peripheral station to at least two central stations;

receiving and transmitting digital signals in a low frequency unit of one of the central stations;

arranging at least said two central stations at a common physical site to cover common parts of a service area,

operating said central and peripheral stations to transmit and receive digital signals by utilizing radio signals at at least one common frequency;

transferring said digital signals between said low frequency unit and a high frequency unit of said central station, said high frequency unit transmitting and receiving said radio signals to and from associated central and peripheral stations; and

redirecting, in response to control means of said low frequency unit, digital signals received by said low frequency unit of a first central station of at least two central stations to the low frequency unit of a second central station of at least two central station to by-pass the high frequency unit of said first central station upon the occurrence of a predetermined condition in order to accomplish transmission redundancy in said common parts of said service area.

2. A method of claim 1 further comprising a step of operating said stations in TDMA frame structures.

3. A method of claim 1 further comprising a step of operating said stations in a CDMA system.

4. A method of claim 1 further comprising a step of operating said stations in a FDMA system.

5. A method of claim 1 further comprising a the step of operating said stations in a combined TDMA and FDMA system.

6. A method of claim 5 further comprising a step of operating said stations in a combined TDMA and CDMA system.

7. A method of claim 5 further comprising a step of selecting alternative antenna polarizations to optimize transmission quality.

8. A method of claim 7 further comprising the steps of:

generating synchronization timing data in one of said central stations; and

transmitting said synchronization timing data from said central station to the peripheral stations associated thereto.

9. A method of claim 8 further comprising a step of signal processing incoming data in said central and peripheral stations to decrease interference and signal deterioration.

10. A wide area radio communication system, comprising:

at least two central stations receiving and transmitting user information and control information as digital signals, each of said central stations being associated with at least one peripheral station and covering a service area which at least in part is common to said two central stations, said central stations and said peripheral stations comprising transmission timing means;

said central and peripheral stations including radio transmission means for transmitting and receiving radio signals;

at least one specific peripheral station being operatively connected to said at least two central stations operating in a common service area and being located in a common physical site;

said two central stations comprising a high frequency unit and a low frequency unit that are operatively connected to each other for transmission of digital signals, said high frequency unit of each of said two central stations comprising said radio transmission means operating at at least one common frequency and means for directing in space said radio transmission to said specific peripheral station; and

the low frequency unit of a first central station of at least two central stations comprising control means for providing redirection of incoming digital signals to the low frequency unit of a second central station to by-pass the high frequency unit of said first central station upon the occurrence of a predetermined condition in order to accomplish transmition redundancy in said common part of said service area.

11. A system of claim 10, wherein at least one peripheral station is a mobile station.

12. A system of claim 10, wherein at least one peripheral station is provided with a directed antenna.

13. A system of claim 10, wherein:

at least two central stations are arranged in one service area to cover a common set of peripheral stations, so as to provide redundancy in said service area; and

said central stations are operatively connected, so as to separate in time the transmission from different central stations to each of said peripheral stations.

14. A system of claim 10, wherein:

at least two central stations are arranged in one service area to cover a common set of peripheral stations, so as to increase capacity in said service area; and

said central stations are operatively connected, so as to separate in time the transmission from different central stations to each of said peripheral stations.

15. A system of claim 10, wherein said high frequency unit of a central station is arranged in a fixed location.

16. A system of claim 10, wherein at least said high frequency unit of a central station is arranged in a satellite.

17. A system of claim 10, wherein at least one peripheral station is provided with an omnidirectional antenna.

18. A system of claim 17, wherein CDMA is used in combination with spread spectrum modulation.

19. A system of claim 17, wherein the system is operating in TDMA.

20. A system of claim 17, wherein the system is operating in a combination of TDMA and CDMA.

21. A system of claim 17, wherein the system is operating in on a time division duplex basis.

22. A system of claim 17, wherein the system is operating in on a frequency division duplex basis.

23. A system of claim 17, wherein low frequency units of at least two central stations are integrated in an external switching system.

24. A system of claim 17, wherein the system is integrated in a GSM system.

25. A system of claim 17, wherein that the system is integrated in a PCN system.

26. A system of claim 17, wherein the system is integrated in a DECT system.

27. A system of claim 17, wherein spread spectrum modulation is implemented therein.

28. A system of claim 27, wherein frequency hopping is used in combination with spread spectrum modulation.