INPUT DRIVE CONTROL FOR SWITCHER REGULATED POWER AMPLIFIER MODULES

• US 20100233978A1
• Filed: 05/21/2010
• Published: 09/16/2010
• Est. Priority Date: 06/14/2006
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Chan, Wen-Yen, Khan, Nasserullah
• Granted Patent: US 8,295,397 B2
• Time in Patent Office: Days
• US Class Current: 455/127.200
• CPC Class Codes: H03F 1/02 Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
• CPC Class Codes: H03F 1/0227 using supply converters
• CPC Class Codes: H03F 1/34 Negative-feedback-circuit arrangements with or without positive feedback H03F1/02 - H03F1/30, H03F1/38 - H03F1/50, H03F3/50 take precedence ; for rejection of common mode signals H03F3/45479
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03G 11/00 Limiting amplitude; Limiting rate of change of amplitude ; Clipping in general
• CPC Class Codes: H03G 3/004 Control by varying the supply voltage
• CPC Class Codes: H03G 3/3042 in modulators, frequency-changers, transmitters or power amplifiers transmission power control in bidirectional transmission systems H04W52/04
• CPC Class Codes: H03G 7/04 incorporating negative feedback
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 2001/0433 with linearisation using feedback
• CPC Class Codes: H04B 2001/045 with means for improving efficiency

Abstract

Various embodiments described herein relate to a power management block and an amplification block used in the transmitter of a communication subsystem. The power management block provides improved control for the gain control signal provided to a pre-amplifier and the supply voltage provided to a power amplifier which are both in the amplification block. The power expended by the power amplifier is optimized by employing a continuous control method in which one or more feedback loops are employed to take into account various characteristics of the transmitter components and control values.

Claims

1. A control system for a transmitter of a wireless device, the transmitter having a pre-amplifier and a power amplifier coupled to an output of the pre-amplifier, the control system comprising:

a switching regulator control block configured to generate a switching supply control signal based on a pre-amplified transmission signal provided at the output of the pre-amplifier, the switching supply control signal comprising control values for a switched mode power supply configured to generate a supply voltage signal for the power amplifier in response to the switching supply control signal; and

a compensating control block configured to generate a gain correction signal based on the supply voltage signal generated by the switched mode power supply, the gain correction signal for adjusting a gain control signal provided to the pre-amplifier for controlling gain in the pre-amplifier.

2. The control system of claim 1, further comprising a summer configured to generate the gain control signal by subtracting the gain correction signal from an automatic gain control signal.

3. The control system of claim 1, further comprising:

a summer configured to subtract the gain correction signal from an automatic gain control signal to generate a modified automatic gain control signal; and

a power limit control block configured to generate the gain control signal based on the modified automatic gain control signal, the pre-amplified transmission signal, and a transmit power limit signal for limiting transmission power of the transmitter.

4. The control system of claim 1, wherein at least one of the switching regulator control block and the compensating control block are implemented in a processor.

5. The control system of claim 4, wherein at least one of the switching regulator control block and the compensating control block are configured to apply a transfer function.

6. The control system of claim 5, wherein the transfer function is defined in the processor using one or more look-up tables.

7. The control system of claim 3, wherein the power limit control block is implemented in a processor and is configured to apply a transfer function defined in the processor using one or more look-up tables to generate the gain control signal.

8. A method of controlling a transmitter of a wireless device, the transmitter having a pre-amplifier and a power amplifier coupled to an output of the pre-amplifier, the method comprising:

generating a switching supply control signal based on a pre-amplified transmission signal provided at the output of the pre-amplifier, the switching supply control signal comprising control values for a switched mode power supply;

providing the switching supply control signal to the switched mode power supply to generate a supply voltage signal for the power amplifier in response to the switching supply control signal;

generating a gain correction signal based on the supply voltage signal;

adjusting a gain control signal using the gain correction signal for controlling gain in the pre-amplifier; and

providing the gain control signal to the pre-amplifier.

9. The method of claim 8, further comprising subtracting the gain correction signal from an automatic gain control signal to generate the gain control signal.

10. The method of claim 8, further comprising

subtracting the gain correction signal from an automatic gain control signal to generate a modified automatic gain control signal;

and

generating the gain control signal based on the modified automatic gain control signal, the pre-amplified transmission signal, and a transmit power limit signal for limiting transmission power of the transmitter.

11. The method of claim 8, wherein at least one of the switching supply control signal and the gain correction signal are generated in a processor.

12. The method of claim 11, further comprising applying a transfer function to generate at least one of the switching supply control signal and the gain correction signal.

13. The method of claim 12, further comprising defining the transfer function in the processor using one or more look-up tables.

14. The method of claim 10, wherein the gain control signal is generated in a processor, and the method further comprises applying a transfer function defined in the processor using one or more look-up tables to generate the gain control signal.

15. A computer-readable storage medium storing instructions executable by a processor coupled to the storage medium, the instructions, when executed by the processor, cause the processor to perform acts of a method of controlling a transmitter of a wireless device, the transmitter having a pre-amplifier and a power amplifier coupled to an output of the pre-amplifier, said acts comprising:

generating a switching supply control signal based on a pre-amplified transmission signal provided at the output of the pre-amplifier, the switching supply control signal comprising control values for a switched mode power supply;

providing the switching supply control signal to the switched mode power supply to generate a supply voltage signal for the power amplifier in response to the switching supply control signal;

generating a gain correction signal based on the supply voltage signal;

adjusting a gain control signal using the gain correction signal for controlling gain in the pre-amplifier; and

providing the gain control signal to the pre-amplifier.

16. The computer-readable storage medium of claim 15, wherein said acts further comprise subtracting the gain correction signal from an automatic gain control signal to generate the gain control signal.

17. The computer-readable storage medium of claim 15, wherein said acts further comprise:

subtracting the gain correction signal from an automatic gain control signal to generate a modified automatic gain control signal; and

generating the gain control signal based on the modified automatic gain control signal, the pre-amplified transmission signal, and a transmit power limit signal for limiting transmission power of the transmitter.

18. The computer-readable storage medium of claim 15, wherein said acts further comprise applying a transfer function to generate at least one of the switching supply control signal and the gain correction signal.

19. The computer-readable storage medium of claim 18, wherein said acts further comprise defining the transfer function in the processor using one or more look-up tables.

20. The computer-readable storage medium of claim 17, wherein said acts further comprise applying a transfer function defined in the processor using one or more look-up tables to generate the gain control signal.