Wireless repeater implementing low-level oscillation detection and protection for a duplex communication system

• US 7,706,744 B2
• Filed: 05/26/2005
• Issued: 04/27/2010
• Est. Priority Date: 05/26/2004
• Status: Active Grant

• Current Assignee: zBoost Incorporated (Wilson Electronics Holdings LLC)
• Original Assignee: Wireless Extenders (Wilson Electronics Holdings LLC)
• Inventors: Rodgers, Michael W., Kim, Stephen W.
• Primary Examiner(s): Nguyen; Duc
• Assistant Examiner(s): Nguyen; Hai V
• Application Number:
  US11/138,010
• Publication Number:
  US 20050272367A1
• Time in Patent Office: 1,797 Days
• Field of Search: 455/11.1
• US Class Current: 455/11.1
• CPC Class Codes: H04B 7/15564 Relay station antennae loop interference reduction
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels

Abstract

A modular wireless repeater typically deployed with a roof-mounted tower-signal antenna and a base unit with a base unit antenna located within the building, to which the tower-signal antenna and the base unit are connected by the user or a satellite TV installer using a 75Ω coaxial cable. The system allows a customer to purchase a unit for all wireless service providers in a given frequency band, such as Cellular, PCS, GSM900, or DCS, etc., and then add on modules for additional types of service that the customer may desire in the future. The system also detects and prevents low-level oscillations. The wireless repeater also performs intelligent power control allowing it to function properly with near and far base unit antennas as well as near and far mobile stations.

Claims

1. A wireless repeater comprising a base unit antenna, a tower-signal antenna, and a bi-directional amplifier configured to send duplex repeater signals between the base unit antenna and the tower-signal antenna, the bi-directional amplifier comprising:

oscillation detection circuitry configured to detect feedback oscillations occurring in the repeater signals by discriminating the feedback oscillations from valid CDMA communication signals occurring in the repeater signals by detecting a power amplitude envelope occurring in the repeater signals and a high frequency content occurring in the power amplitude envelope indicative of CDMA communication signals; and

oscillation protection circuitry configured to decrease or disconnect power to at least one component of the bi-directional amplifier in response to the detection of feedback oscillations.

2. The wireless repeater of claim 1, wherein the oscillation detection circuitry is further configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from characteristics associated with one or more of TDMA, GSM, or AMPS communication signals.

3. The wireless repeater of claim 1, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from characteristics associated with TDMA, GSM, AMPS and CDMA communication signals.

4. The wireless repeater of claim 1, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by determining whether the repeater signals comprise one or more of pulsed signal characteristics, full duplex signal characteristics, or amplitude modulated signal characteristics.

5. The wireless repeater of claim 1, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from pulsed signal characteristics, full duplex signal characteristics, and amplitude modulated signal characteristics.

6. The wireless repeater of claim 1, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by determining whether the repeater signals comprise pulsed signal characteristics.

7. The wireless repeater of claim 6, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by determining whether the repeater signals comprise pulsed signal characteristics associated with TDMA or GSM communication signals.

8. The wireless repeater of claim 6, wherein the oscillation detection circuitry comprises peak-to-average circuitry configured to determine whether the repeater signals comprise pulsed signal characteristics.

9. The wireless repeater of claim 1, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by determining whether the repeater signals comprise full duplex signal characteristics.

10. The wireless repeater of claim 9, wherein the oscillation detection circuitry comprises frequency detection circuitry configured to determine whether the repeater signals comprise full duplex signal characteristics.

11. The wireless repeater of claim 10, wherein the frequency detection circuitry comprises:

a mixer configured to combine uplink and downlink signals of the bidirectional amplifier to create a mixed duplex signal;

a filter configured to receive the mixed duplex signal and produce a filtered mixed duplex signal by band-pass filtering the mixed duplex signal; and

a power detection circuit configured to determine a power level associated with the filtered mixed duplex signal.

12. The wireless repeater claim 11, wherein the oscillation detection circuitry is configured to determine whether the filtered mixed duplex signal comprises characteristics associated with AMPS communication signals.

13. The wireless repeater of claim 10, wherein the frequency detection circuitry is configured to detect the valid CDMA signals by detecting signal components having significant amplitudes occurring in uplink and downlink communication channels associated with CDMA communication signals.

14. The wireless repeater of claim 10, wherein the frequency detection circuitry is configured to detect signal components having significant amplitudes occurring in uplink and downlink communication channels associated with TDMA or GSM communication signals.

15. The wireless repeater of claim 14, wherein the amplitude modulation detection circuitry comprises analog continuous wave detection circuitry.

16. The wireless repeater of claim 1, wherein the oscillation detection circuitry comprises amplitude modulation detection circuitry.

17. The wireless repeater of claim 1, further comprising isolation management circuitry configured to automatically increase a gain setting of the bi-directional amplifier periodically to a feedback-triggering level that triggers initiation of the feedback oscillations;

and

oscillation protection circuitry configured to automatically decrease power to at least one component of the bi-directional amplifier from the feedback-triggering level to initialize the gain at a desired level.

18. A wireless repeater comprising a base unit antenna, a tower-signal antenna, and a bi-directional amplifier configured to send duplex repeater signals between the base unit antenna and the tower-signal antenna, the bi-directional amplifier comprising:

oscillation detection circuitry configured to detect feedback oscillations occurring in the repeater signals;

isolation management circuitry configured to automatically increase a gain setting of the bi-directional amplifier periodically to a feedback-triggering level that triggers initiation of the feedback oscillations; and

oscillation protection circuitry configured to automatically decrease power to at least one component of the bi-directional amplifier from the feedback-triggering level to initialize the gain at a desired level.

19. The wireless repeater of claim 18, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from characteristics associated with one or more of TDMA, GSM, or AMPS communication signals.

20. The wireless repeater of claim 18, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from characteristics associated with TDMA, GSM, AMPS and CDMA communication signals.

21. The wireless repeater of claim 18, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by determining whether the repeater signals comprise one or more of pulsed signal characteristics, full duplex signal characteristics, or amplitude modulated signal characteristics.

22. The wireless repeater of claim 18, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from pulsed signal characteristics, full duplex signal characteristics, and amplitude modulated signal characteristics.

23. A wireless repeater system comprising:

a first wireless repeater, comprising a tower-signal antenna, a first base unit antenna, and a first bi-directional amplifier electrically connected between the tower signal antenna and the base unit antenna;

wherein the first bi-directional amplifier is configured to transmit and receive duplex communication signals in a first frequency band via the tower-signal antenna, amplify and deliver downlink communication signals in the first frequency band to the first base unit antenna, receive uplink communication signals in the first frequency band from the first base unit antenna, and amplify and deliver the uplink communication signals in the first frequency band to the tower-signal antenna; and

wherein the first bi-directional amplifier is further configured to transmit and receive duplex communication signals in a second frequency band via the tower-signal antenna, route downlink communication signals in the second frequency band to an output port, receive uplink communication signals in the second frequency band from the output port, and deliver the uplink communication signals in the second frequency band to the tower-signal antenna; and

wherein the first wireless repeater is configured for connection via the output port to a second wireless repeater without a tower signal antenna comprising a second bi-directional amplifier and a second base unit antenna operatively connected to the output port of the first wireless repeater configured to receive the downlink communication signals in the second frequency band from the output port, amplify and deliver the downlink communication signals in the second frequency band to the second base unit antenna, receive uplink communication signals in the second frequency band from the second base unit antenna, and amplify and deliver the uplink communication signals in the second frequency band to the output port.

24. The wireless repeater system of claim 23, further comprising the second bi-directional amplifier removably connected to the first wireless repeater via the output port, configured to receive the downlink communication signals in the second frequency band from the output port, amplify and deliver the downlink communication signals in the second frequency band to a second base unit antenna, receive uplink communication signals in the second frequency band from the second base unit antenna, and amplify and deliver the uplink communication signals in the second frequency band to the first wireless repeater via the output port.

25. The wireless repeater of claim 24, wherein the first and second bi-directional amplifiers further comprise:

oscillation detection circuitry configured to detect feedback oscillations occurring in the repeater signals;

isolation management circuitry configured to periodically increase a gain setting of the bi-directional amplifier to trigger initiation of the feedback oscillations; and

oscillation protection circuitry configured to decrease power to at least one component of the bi-directional amplifier in response to the detection of feedback oscillations.

26. The wireless repeater of claim 24, wherein the first and second bi-directional amplifiers further comprise:

oscillation detection circuitry configured to detect feedback oscillations occurring in the repeater signals by discriminating the feedback oscillations from CDMA communication signals occurring in the repeater signals; and

oscillation protection circuitry configured to decrease or disconnect power to at least one component of the bi-directional amplifier in response to the detection of feedback oscillations.

27. The wireless repeater of claim 26, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from characteristics associated with one or more of TDMA, GSM, or AMPS communication signals.

28. The wireless repeater of claim 26, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from characteristics associated with TDMA, GSM, AMPS and CDMA communication signals.

29. The wireless repeater of claim 26, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by determining whether the repeater signals comprise pulsed signal characteristics, full duplex signal characteristics, or amplitude modulated signal characteristics.

30. The wireless repeater of claim 26, wherein the oscillation detection circuitry is configured to discriminate feedback oscillations from valid communication signals by distinguishing the repeater signals from pulsed signal characteristics, full duplex signal characteristics, and amplitude modulated signal characteristics.

31. A wireless repeater system comprising:

a first wireless repeater comprising a tower signal antenna, a first bidirectional amplifier, a first base unit antenna, a diplexer, and an output port configured to amplify and deliver signals received from the tower signal antenna in a first frequency band to the first base unit antenna, and further configured to deliver signals received from the tower signal antenna in a second frequency band to the output port; and

a second wireless repeater without a tower signal antenna comprising a second bidirectional amplifier and a second base unit antenna operatively connected to the output port and configured to amplify and deliver signals received from the output port in the second frequency band to the second base unit antenna.

32. The wireless repeater system of claim 31, wherein the communication signals in the first frequency band are encoded using a first type of modulation, and the communication signals in the second frequency band are encoded using a second type of modulation.