Active antenna array and method for relaying radio signals with synchronous digital data interface

• US 8,774,196 B2
• Filed: 06/03/2010
• Issued: 07/08/2014
• Est. Priority Date: 06/03/2010
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Kathrein-Werke KG. (Kathrein SE)
• Inventors: Schmidt, Georg, Schlee, Johannes
• Primary Examiner(s): Elliott, IV, Benjamin H
• Application Number:
  US12/792,925
• Publication Number:
  US 20110299430A1
• Time in Patent Office: 1,496 Days
• Field of Search: 370/277, 370/278, 370/310.2, 370/328, 370/334, 370/395.62, 370/339, 342/74, 342359-360, 342380-386, 343745-782, 343828-843, 375295-352
• US Class Current: 370/395.62
• CPC Class Codes: H04B 7/0671 using different delays between antennas
• CPC Class Codes: H04B 7/0682 using phase diversity (e.g. phase sweeping)

Abstract

The present disclosure relates to an active antenna array for a mobile communications network. The active antenna comprises a base band unit coupled to a base station, a plurality of transceiver units and at least one link. The plurality of transceiver units is terminated by at least one antenna element. The at least one link couples individual ones of the plurality of transceiver units to the base band unit 10. The at least one link is a digital link and is adapted to relay an individual transmit signal concurrently and in synchronisation with a transmit clock signal. The present disclosure further teaches a method for relaying radio signals in a mobile communications network. The present disclosure further relates to a computer program enabling a computer to manufacture the active antenna array of the present disclosure and to execute the method of relaying radio signal in a mobile communications system.

Claims

1. An active antenna array for a mobile communications network, the active antenna array comprising:

a base band unit coupled to a base station;

a plurality of transceiver units, wherein individual ones of the plurality of transceiver units are terminated by at least one antenna element;

a measurement unit, connected with one of the plurality of transceiver units via a feedback path, wherein the measurement unit is operable to measure at least one of a transmit phase deviation, a transmit amplitude deviation, and a transmit delay;

at least one adjustment unit in either the base band unit or one of the plurality of transceiver units for imposing at least one of a transmit phase compensation, a transmit amplitude compensation and a transmit delay compensation on the individual transmit signals; and

at least one link coupling the individual ones of the plurality of transceiver units to the base band unit;

wherein the at least one link is a digital link and is configured to relay an individual transmit signal concurrently and in synchronization with a transmit clock signal,

wherein the transmit clock signal defines a sampling time of an individual digital to analogue converter converting the individual transmit signal;

wherein the transmit delay compensation is imposed on the individual transmit signals based on said sampling time before relaying the individual transmit signals across the link.

2. The active antenna array according to claim 1, wherein the at least one link is further configured to relay an individual receive signal concurrently and in synchronisation with the receive clock signal.

3. The active antenna array according to claim 2, wherein the receive clock signal is in synchronisation to the transmit clock signal.

4. The active antenna array according to claim 1, wherein the at least one link is configured to relay control information and maintenance information between the base band unit and individual ones of the transceiver units.

5. The active antenna array according to claim 1, wherein the base band unit is configured to provide at least one of a individual transmit signal, the transmit clock signal and the receive clock signal to an individual one of the transceiver units.

6. The active antenna array according to claim 1, wherein at least one of the transmit clock signal and a receive clock signal are generateable in response to a base station signal received from the base station.

7. The active antenna array according to claim 1, wherein the transmit clock signal corresponds to a transmit sampling rate of the individual transmit signal.

8. The active antenna array according to claim 1, wherein a receive clock signal corresponds to a receive sampling rate of the individual receive signal.

9. The active antenna array according to claim 1, wherein a receive clock signal defines a sampling time of an individual analogue to digital converter converting the individual receive signal.

10. The active antenna array according to claim 1, comprising:

a plurality of transmit amplifiers for amplifying the individual transmit signal transmitted by individual ones of the transceiver units.

11. The active antenna array according to claim 1, comprising:

a plurality of receive amplifiers for amplifying an individual receive signal received by individual ones of the transceiver units.

12. The active antenna array according to claim 1, comprising:

at least one adjustment unit configured to apply at least one of a variable delay, a variable phase weighting and a variable amplitude weighting to a signal passing an individual one of the links.

13. The active antenna array according to claim 1, comprising:

at least one processing element for signal processing within an individual one of the transceiver units, the at least one processing element being selected from the group consisting of;

a digital filtering element, an analogue filtering element, a duplex filter, an equalizer and a mixer.

14. The active antenna array according to claim 1, comprising:

at least one feedback path from an individual one of the antenna elements to a measurement unit;

the feedback path relaying a feedback signal, the feedback signal comprising at least one of one or more coupled transmit signals being coupled from signals transmit by the individual one of the antenna elements or one or more coupled receive signals being coupled from signals received by the individual one of the antenna elements.

15. The active antenna array according to claim 14, the measurement unit being configured to:

measure a transmit deviation accumulated when transmitting using an individual one of the transceiver units;

wherein the transmit deviation comprises at least one of an transmit amplitude deviation, a transmit phase deviation and a transmit delay compensation.

16. The active antenna array according to claim 14, the measurement unit being configured to:

measure a receive deviation accumulated when receiving using an individual one of the transceiver units;

wherein the receive deviation comprises at least one of a receive amplitude deviation, a receive phase deviation and a receive delay deviation.

17. A method for relaying radio signals in a mobile communications network, the method comprising:

generating a transmit clock signal;

compensating deviations;

relaying an individual transmit signal concurrently and in synchronisation with the transmit clock signal along at least one link,

wherein the transmit clock signal defines a sampling time of an individual digital to analogue converter converting the individual transmit signal;

measuring at least one of a transmit phase deviation, a transmit amplitude deviation, and a transmit delay; and

imposing at least one of a transmit phase compensation, a transmit amplitude compensation and a transmit delay compensation on the individual transmit signals,

wherein the transmit delay compensation is imposed on the individual transmit signals based on said sampling time before relaying the individual transmit signals across the link.

18. The method according to claim 17, further comprising:

generating a receive clock signal;

relaying an individual receive signal concurrently and in synchronisation with the receive clock signal along the at least one link.

19. The method according to claim 17, further comprising:

compensating deviations between individual ones of the transceiver units.

20. The method according to claim 19, the compensating comprising:

determining and correcting transmit deviations between the individual transmit signal relayed by individual ones of the transceiver units; and

determining and correcting receive deviations between the individual receive signal received by individual transceiver units.

21. The method according to claim 20, the determining and correcting of transmit deviations comprising:

extracting at least one coupled transmit signal;

measuring transmit deviations between individual ones of the coupled transmit signals;

calculating transmit compensations; and

imposing transmit compensations.

22. The method according to claim 20, the determining and correcting of receive deviations comprising:

extracting at least one coupled receive signal;

measuring receive deviations between individual ones of the coupled receive signals;

calculating receive compensations; and

imposing receive compensations.

23. A computer program product stored on a non-transitory medium and comprising a non-volatile computer usable medium having control logic stored therein for causing a computer to manufacture an active antenna array for a mobile communications network, the active antenna array comprising:

a base band unit coupled to a base station;

a plurality of transceiver units terminated by at least one antenna element;

a measurement unit for measuring at least one of a transmit phase deviation, a transmit amplitude deviation, and a transmit delay; and

at least one adjustment unit for imposing at least one of a transmit phase compensation, a transmit amplitude compensation and a transmit delay compensation on the individual transmit signals;

at least one link coupling the individual ones of the plurality of transceiver units to the base band unit;

wherein the at least one link is a digital link and is configured to relay an individual transmit signal concurrently and in synchronisation with a transmit clock signal,

wherein the transmit clock signal defines a sampling time of an individual digital to analogue converter converting the individual transmit signal; and

wherein the transmit delay compensation is imposed on the individual transmit signals based on said sampling time before relaying the individual transmit signals across the link.

a plurality of receive amplifiers for amplifying an individual receive signal received by individual ones of the transceiver units.

24. A computer program product stored on a non-transitory medium and comprising a non-volatile computer usable medium having control logic stored therein for causing a computer to relay radio signals in a mobile communications network, the control logic comprising:

first computer readable program code for causing the computer to generate a transmit clock signal;

second computer readable program code for causing the computer to compensate deviations;

third computer readable program code for causing the computer to relay an individual transmit signal concurrently and in synchronisation with the transmit clock signal along at least one link;

fourth computer readable program code for causing the computer to measure at least one of a transmit phase deviation, a transmit amplitude deviation, and a transmit delay; and

fifth computer readable program code for causing the computer to impose at least one of a transmit phase compensation, a transmit amplitude compensation and a transmit delay compensation on the individual transmit signals;

wherein a transmit clock signal defines a sampling time of an individual digital to analogue converter converting an individual transmit signal; and

wherein the transmit delay compensation is imposed on the individual transmit signals based on said sampling time before relaying the individual transmit signals across the link.