Methods and apparatus for adjusting DC power consumption in mobile handset

• US 6,633,750 B1
• Filed: 09/10/1999
• Issued: 10/14/2003
• Est. Priority Date: 05/18/1998
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Morris, Russell A., Dacus, Farron L.
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): Ferguson, Keith
• Application Number:
  US09/393,508
• Time in Patent Office: 1,495 Days
• Field of Search: 455/126, 455/127, 455/522, 455/69, 455/118, 455/550, 455/517, 455/115, 455/343, 455/574, 455/572, 455/67.1, 455/422, 455/425, 455/403, 455/423, 455/424
• US Class Current: 455/126
• CPC Class Codes: H03F 1/0211 with control of the supply voltage or current
• CPC Class Codes: H03F 2200/504 the supply voltage or current being continuously controlled by a controlling signal, e.g. the controlling signal of a transistor implemented as variable resistor in a supply path for, an IC-block showed amplifier
• CPC Class Codes: H03F 2200/507 A switch being used for switching on or off a supply or supplying circuit in an IC-block amplifier circuit
• 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

Abstract

Apparatus and methods are provided for regulating the power consumption within a wireless communications mobile handset. A base station transmits an RF power output designating signal that indicates a desired level of the RF power output from the mobile handset. The mobile handset receives the RF power output designating signal, where it is used to set the level of the DC power supplied to the mobile handset. In this manner, the minimum amount of power necessary to maintain linear operation of the mobile handset is expended in the mobile handset. The DC power level is set by internally generating a control signal. The level of the control signal is dictated by the desired level of the RF power output as indicated by the received RF power output designating signal. The control signal is then applied to an RF amplifier circuit contained within the mobile handset to set the DC power level. The DC power level can be further varied from the set DC power level in proportion to an envelope of an RF input signal to provide a more power-efficient mobile handset.

Claims

1. A method of regulating the DC power consumption in a wireless communications mobile unit, the method comprising:

providing DC power within said mobile unit;

transmitting a command signal from a base station, said command signal indicating a desired power level of an RF signal output from said mobile unit;

receiving said command signal at said mobile unit; and

setting a level of said DC power based on said command signal;

wherein said DC power produces a supply current in an RF amplifier circuit within said mobile unit, and wherein said DC power level is set by;

generating a control signal within said mobile unit, wherein a level of said control signal is selected based on said command signal;

generating a supply current tracking signal indicating the present level of said supply current;

determining the difference between at least said control signal and at least said supply current tracking signal to obtain a biasing signal; and

varying said supply current in proportion to said biasing signal.

2. The method of claim 1, further comprising varying said DC power level from said set DC power level by:

applying a modulated RF signal on an input terminal of said RF amplifier circuit, said modulated RF signal having an envelope; and

varying said set DC power level in proportion to said envelope.

3. The method of claim 2, wherein said DC power level is varied from said set DC power level by:

sensing said RF output signal to produce a sampled envelope signal; and

adding said sampled envelope signal to said control signal.

4. The method of claim 1, wherein said mobile unit comprises an RF amplifier circuit, and wherein said DC power level substantially equals the minimum value required to maintain linear operation of said RF amplifier circuit.

5. The method of claim 1, wherein said mobile unit comprises an RF amplifier circuit, and wherein said DC power level is set by:

generating a control signal within said mobile unit, wherein a level of said control signal is selected based on said command signal; and

applying said control signal to said RF amplifier circuit.

6. The method of claim 5, wherein said control signal level is selected from a plurality of control signal levels, each of said plurality of control signal levels corresponding to a respective plurality of RF power output levels.

7. The method of claim 1, wherein said RF output signal is modulated, the method further comprising varying said DC power level from said set DC power level in proportion to an envelope of said modulated RF output signal.

8. The method of claim 7, wherein said DC power level is varied from said set DC power level by:

sensing said modulated RF output signal to produce a sampled envelope signal; and

adding said sampled envelope signal to said control signal.

9. A method of regulating the DC power consumption in a wireless communications mobile unit, the method comprising:

providing DC power within said mobile unit;

transmitting a command signal from a base station, said command signal indicating a desired power level of an RF signal output from said mobile unit;

receiving said command signal at said mobile unit; and

setting a level of said DC power based on said command signal;

wherein said DC power produces a supply voltage across an RF amplifier circuit within said mobile unit, and wherein said DC power level is set by;

generating a control signal within said mobile unit, wherein a level of said control signal is selected based on said command signal;

generating a supply current tracking signal indicating the present level of said supply voltage;

determining the difference between at least said control signal and at least said supply voltage tracking signal to obtain a biasing signal; and

varying said supply voltage in proportion to said biasing signal.

10. The method of claim 9, further comprising varying said DC power level from said set DC power level by:

applying a modulated RF signal on an input terminal of said RF amplifier circuit, said modulated RF signal having an envelope; and

varying said set DC power level in proportion to said envelope.

11. The method of claim 10, wherein said DC power level is varied from said set DC power level by:

sensing said RF output signal to produce a sampled envelope signal;

and adding said sampled envelope signal to said control signal.

12. A method of regulating the DC power consumption in a wireless communications mobile unit, the method comprising:

providing DC power within said mobile unit;

transmitting a command signal from a base station, said command signal indicating a desired power level of an RF signal output from said mobile unit;

receiving said command signal at said mobile unit; and

setting a level of said DC power based on said command signal;

wherein said mobile unit comprises a driver and an RF amplifier circuit, and wherein said command signal indicates one of a high RF output power condition and a low RF output power condition, and wherein said DC power level is set by;

amplifying an RF signal through said driver;

providing said DC power to said RF amplifier circuit and amplifying said RF signal through said RF amplifier circuit in response to said high RF amplifier circuit; and

bypassing further amplification of said RF signal though said RF amplifier circuit in response to said low RF output power condition.

13. The method of claim 12, wherein said mobile unit is a mobile handset.

14. The method of claim 12, wherein said command signal is an RF power output designating signal.

15. A mobile unit for a wireless communications system, comprising:

an RF amplifier circuit;

means for supplying DC power to said RF amplifier circuit;

means for receiving a command signal transmitted to said mobile unit, said command signal indicating a desired power level of an RF signal output from said RF amplifier circuit, and

means for setting a level of said DC power based on said command signal;

wherein said DC power supply means produces a supply current in said RF amplifier circuit, and said DC power level setting means comprises;

means for generating a control voltage within said mobile unit;

mans for generating a supply current tracking voltage;

means for determining the difference between at least said control voltage and at least said supply current tracking voltage to obtain a biasing signal; and

means for varying said supply current with said biasing signal.

16. The mobile unit of claim 15, further comprising means for varying said set DC power level in proportion to the envelope of an RF modulated input signal.

17. The mobile unit of claim 15, wherein said DC power level substantially equals the minimum value required to maintain linear operation of said RF amplifier circuit.

18. A mobile unit for a wireless communications system, comprising:

an RF amplifier circuit;

means for supplying DC power to said RF amplifier circuit;

means for receiving a command signal transmitted to said mobile unit, said command signal indicating a desired power level of an RF signal output from said RF amplifier circuit, and

means for setting a level of said DC power based on said command signal;

wherein said DC power supply means produces a supply voltage across said RF amplifier circuit, said DC power supply means comprising an internal source voltage, and wherein said DC power level setting means comprises;

means for generating a control voltage within said mobile unit;

means for generating a supply voltage tracking voltage;

means for determining the difference between at least said control voltage and at least said supply voltage tracking voltage to obtain a biasing signal; and

means for varying said internal source voltage with said biasing signal.

19. The mobile unit of claim 18, further comprising means for varying said set DC power level in proportion to the envelope of an RF modulated input signal.

20. A mobile unit for a wireless communications system, comprising:

an RF amplifier circuit;

means for supplying DC power to said RF amplifier circuit;

means for receiving a command signal transmitted to said mobile unit, said command signal indicating a desired power level of an RF signal output from said RF amplifier circuit, and

means for setting a level of said DC power based on said command signal;

wherein said command signal indicates one of a high RF output power condition and a low RF output power condition, and wherein said DC power level setting means comprises;

pre-amplification means;

means for supplying said DC power to said RF amplifier circuit during said high RF output power condition and impeding said DC power to said RF amplifier circuit during said low RF output power condition; and

means for electrically coupling the output of said pre-amplification means to the input of said RF amplifier circuit during said high RF output power condition and electrically coupling the output of said pre-amplification means to the output of said RF amplifier circuit during said low RF output condition.

21. The mobile unit of claim 20, wherein said command signal is an RF power output designating signal.