Distributed power amplifier architecture for TCAS transmitter

• US 20020014986A1
• Filed: 04/13/2001
• Published: 02/07/2002
• Est. Priority Date: 04/14/2000
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Ringwald, Rand, Pham, Dang, Nguyen, Lien, Jones, James B., Brandao, Ruy C., Brandao, Ruy L.
• Granted Patent: US 6,587,069 B2
• Time in Patent Office: Days
• US Class Current: 342/30
• CPC Class Codes: G01S 13/767 Responders; Transponders teaching or practice apparatus for gun-aiming or gun-laying using reflecting targets or active targets F41G3/26
• CPC Class Codes: G01S 13/933 of aircraft or spacecraft
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: G01S 7/406 using internally generated reference signals, e.g. via delay line, via RF or IF signal injection or via integrated reference reflector or transponder

Abstract

A transmitter and method for transmitting transponder or TCAS signals uses linear amplification to save on circuit component weight, cost and size while enabling precise amplification and control of the transmitted signal.

Claims

1. A method for amplifying one of a transponder or TCAS signals for subsequent transmission from an aircraft, the method comprising the steps of:

receiving one of a transponder or TCAS signal to be transmitted;

passing said signal through a plurality of amplifiers arranged in series; and

using a control signal to control a power level of said plurality of amplifiers whereby a total amplification of said signal is determined.

2. The method of claim 1 wherein said step of passing said signal through a plurality of amplifiers comprises the step of passing said signal through a plurality of Class A/B amplifiers.

3. An amplifier stage for a TCAS transmitter comprising:

. an input for receiving a TCAS signal to be transmitted;

a plurality of amplifiers arranged in series for amplifying said TCAS signal; and

a controller coupled to at least one of said plurality of amplifiers for controlling a power level of said amplifier.

4. The amplifier stage of claim 3 wherein said plurality of amplifiers comprise linear Class A/B amplifiers.

5. The amplifier stage of claim 3 wherein said controller comprises a programmable logic device.

6. The amplifier stage of claim 3 further comprising a whisper/shout attenuator disposed between said input and said plurality of amplifiers.

7. The amplifier of stage of claim 6 wherein said whisper/shout attenuator comprises a programmable integrated circuit.

8. An amplifier stage for a transponder transmitter comprising:

. an input for receiving a signal to be transmitted;

a plurality of amplifiers arranged in series for amplifying said signal; and

a controller coupled to at least one of said plurality of amplifiers for controlling a power level of said amplifier.

9. The amplifier stage of claim 8 wherein said plurality of amplifiers . comprise linear Class A/B amplifiers.

10. The amplifier stage of claim 8 wherein said controller comprises a. programmable logic device.

11. A TCAS transmitter for transmitting a TCAS signal from an airborne antenna comprising:

an input for receiving a TCAS signal to be transmitted;

a power splitter for splitting said TCAS signal onto a plurality of signal lines;

a plurality of linear amplifiers arranged in series on each of said signal lines;

a controller coupled to at least one of said plurality of amplifiers for controlling a power level of said amplifier; and

an output wherein said signal lines are coupled to the antenna.

12. The TCAS transmitter of claim 11 further comprising at least one phase shifter, located on at least one of said signal lines and coupled to an output of said power splitter.

13. The TCAS transmitter of claim 11 wherein said controller comprises a programmable logic device.

14. The TCAS transmitter of claim 11 wherein said power splitter comprises an integrated circuit.

15. The TCAS transmitter of claim 11 further comprising at least one whisper/shout attenuator located on at least one of said signal lines and disposed between said plurality of amplifiers and said power splitter.

16. The TCAS transmitter of claim 15 wherein said whisper/shout attenuator further comprises an integrated circuit.

17. The TCAS transmitter of claim 15 wherein said whisper/shout attenuator is programmable.

18. The TCAS transmitter of claim 17 wherein in said whisper/shout attenuator is coupled to receive an attenuator control signal from said controller.

19. The TCAS transmitter of claim 12 wherein said phase shifter comprises an integrated circuit.

20. The TCAS transmitter of claim 12 wherein said phase shifter comprises an IQ modulator.

21. The TCAS transmitter of claim 12 wherein said phase shifter is disposed between said power splitter and said plurality of amplifiers.

22. The TCAS transmitter of claim 12 wherein a phase shifter is located on each of said plurality of signal lines.

23. The TCAS transmitter of claim 22 wherein said phase shifters operate to perform DPSK modulation of said TCAS signal.

24. The TCAS transmitter of claim 11 wherein said plurality of amplifiers comprise Class A/B amplifiers.