Active array antenna and system for beamforming

• US 20040204109A1
• Filed: 09/30/2002
• Published: 10/14/2004
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: Andrew Corporation (CommScope Holding Company, Inc.)
• Inventors: Hoppenstein, Russell
• Granted Patent: US 7,280,848 B2
• Time in Patent Office: Days
• US Class Current: 455/562.1
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 21/0025 Modular arrays
• CPC Class Codes: H01Q 23/00 Antennas with active circuits or circuit elements integrated within them or attached to them

Abstract

An active antenna array for use in a beamforming antenna system. The antenna array includes multicarrier power amplifiers coupled to each antenna element wherein the outputs of the multicarrier power amplifiers are linearized. The antenna array communicates with a base station control unit located at the base of the cellular tower in digital baseband. Fiber optic transmission lines couple the antenna arrays with the base station control unit. Multicarrier linear power amplifiers may be coupled to the antenna elements to linearize the outputs of the antenna elements. Alternatively, a predistortion circuit is coupled to the antenna elements to linearize the outputs of the antenna elements when multicarrier power amplifiers are used.

Claims

1. An active beamforming antenna, comprising:

an array of antenna elements;

a multicarrier power amplifier operatively coupled to each of the antenna elements of the array;

the outputs of the multicarrier power amplifiers being linearized.

2. The beamforming antenna of claim 1, wherein the multicarrier power amplifiers comprise multicarrier linear power amplifiers.

3. The beamforming antenna of claim 2, wherein the antenna elements are arranged in one or more sub-arrays to define the array, and further wherein each multicarrier linear power amplifier is operatively coupled to an input of the sub-array to operatively couple with the antenna elements.

4. The beamforming antenna of claim 1, further comprising a low noise amplifier operatively coupled to each of the antenna elements of the array.

5. The beamforming antenna of claim 4, wherein the antenna elements are arranged in one or more sub-arrays to define the array, and further wherein each low noise amplifier is operatively coupled to an output of the sub-array to operatively couple with the antenna elements.

6. The beamforming antenna of claim 2, wherein each multicarrier linear power amplifier is operatively coupled proximate each antenna element of the array.

7. The beamforming antenna of claim 4, wherein each low noise amplifier is operatively coupled proximate each antenna element of the array.

8. The beamforming antenna of claim 1 further comprising a duplexer operatively coupled to the antenna elements to facilitate simultaneous transmit and receive functionality.

9. The beamforming antenna of claim 1 further comprising a circulator operatively coupled to the antenna elements to facilitate simultaneous transmit and receive functionality.

10. The beamforming antenna of claim 1 further comprising a predistortion circuit coupled to the multicarrier power amplifiers of a plurality of antenna elements of the array.

11. The beamforming antenna of claim 1 wherein said predistortion circuit has a transfer function similar to a transfer function of a multicarrier power amplifier coupled thereto.

12. An active beamforming antenna, comprising:

an array of antenna elements arranged in one or more sub-arrays to define the array;

a multicarrier power amplifier operatively coupled proximate each of the antenna elements of the array; and

a predistortion circuit operatively coupled to an input of the sub-array to operatively couple with the antenna elements, the predistortion circuit being capable to suppress generation of intermodulation distortion.

13. The beamforming antenna of claim 12, further comprising a low noise amplifier operatively coupled proximate each antenna element of the array.

14. The beamforming antenna of claim 12 further comprising a circulator operatively coupled to the antenna elements to facilitate simultaneous transmit and receive functionality.

15. The beamforming antenna of claim 12 wherein said predistortion circuit has a transfer function similar to a transfer function of a multicarrier power amplifier coupled thereto.

16. A base station, comprising:

a tower;

an antenna supported on the tower and having an array of antenna elements arranged in one or more sub-arrays to define the array;

a control unit associated with the tower and operable to transmit signals to and receive signals from the antenna in digital baseband;

a transceiver operatively coupled to each sub-array and being operable to convert between digital baseband signals and RF signals between the antenna array and control unit; and

a predistortion circuit coupled between the transceiver and each sub-array to reduce intermodulation distortion at the antenna.

17. The base station of claim 16, further comprising at least one fiber optic transmission line coupled to the control unit and the antenna for transmission of the digital baseband signals therebetween.

18. The base station of claim 16, further comprising a multicarrier power amplifier operatively coupled to each of the antenna elements of the array, the outputs of the multicarrier power amplifiers being linearized.

19. The base station of claim 18, wherein the multicarrier power amplifiers comprise multicarrier linear power amplifiers.

20. The base station of claim 19, wherein each multicarrier linear power amplifier is operatively coupled to an input of the sub-array to operatively couple with the antenna elements.

21. The base station of claim 16, further comprising a low noise amplifier operatively coupled to each of the antenna elements of the array.

22. The base station of claim 21, wherein each low noise amplifier is operatively coupled to an output of the sub-array to operatively couple with the antenna elements.

23. The base station of claim 19, wherein each multicarrier linear power amplifier is operatively coupled proximate each antenna element of the array.

24. The base station of claim 21, wherein each low noise amplifier is operatively coupled proximate each antenna element of the array.

25. The base station of claim 16, further comprising a duplexer operatively coupled to the antenna elements to facilitate simultaneous transmit and receive functionality.

26. The base station of claim 16, further comprising a circulator operatively coupled to the antenna elements to facilitate simultaneous transmit and receive functionality.

27. A method of forming a beam at an antenna having an array of antenna elements, comprising:

operatively coupling a multicarrier power amplifier to each of the antenna elements of the array;

linearizing the outputs of the multicarrier power amplifiers; and

applying the linearized outputs of the multicarrier power amplifiers to the antenna elements of the array to form a beam.

28. The method of claim 27, wherein the multicarrier power amplifiers comprise multicarrier linear power amplifiers.

29. The method of claim 27, further comprising the step of:

operatively coupling a low noise amplifier to the antenna elements of the array.

30. The method of claim 27, further comprising the step of:

operatively coupling a predistortion circuit to the multicarrier power amplifiers.

31. A method of forming a beam at an antenna having an array of antenna elements, comprising:

operatively coupling a multicarrier power amplifier to each of the antenna elements of the array;

operatively coupling a predistortion circuit to the multicarrier power amplifiers to linearize the outputs of the multicarrier power amplifiers; and

applying the linearized outputs of the multicarrier power amplifiers to the antenna elements of the array to form a beam.

32. The method of claim 31, wherein the multicarrier power amplifiers comprise multicarrier linear power amplifiers.

33. The method of claim 31, further comprising the step of:

operatively coupling a low noise amplifier to the antenna elements of the array.