Performing power control in a receiver based on environmental noise

• US 8,538,365 B2
• Filed: 09/30/2011
• Issued: 09/17/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Croman, Russell, Gregg, Christopher S., Kasha, Dan B., May, Michael R., Khoury, John, Elenes, Javier
• Primary Examiner(s): Trinh, Sonny
• Application Number:
  US13/249,508
• Publication Number:
  US 20130084818A1
• Time in Patent Office: 718 Days
• Field of Search: 455/143, 455/130, 455/133, 455/135, 455/226.3, 455/277.2, 455/278.1, 455/310, 455/296, 455/522
• US Class Current: 455/310
• CPC Class Codes: H04B 1/06 Receivers
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In one embodiment, a method includes receiving and processing an incoming radio frequency (RF) signal in a receiver. Based on this signal, an environmental noise level can be determined, where this level corresponds to environmental noise present in an environment in which the receiver is located. Then, if the environmental noise level is substantially greater than receiver-generated noise, power consumption of at least one analog front end component of the receiver can be reduced.

Claims

1. A method comprising:

receiving and processing an incoming radio frequency (RF) signal in a receiver;

determining an environmental noise level based on the processed RF signal corresponding to environmental noise present in an environment in which the receiver is located;

obtaining receiver-generated noise from a table in the receiver, wherein the table includes a plurality of entries each associating a power consumption level of the receiver with a receiver-generated noise level; and

if the environmental noise level is substantially greater than the receiver-generated noise, reducing power consumption of at least one analog front end component of the receiver.

2. The method of claim 1, wherein reducing the power consumption comprises disabling at least one of a plurality of parallel stages of a first front end component of the receiver.

3. The method of claim 2, wherein reducing the power consumption comprises disabling at least one of a plurality of parallel stages of a second front end component of the receiver.

4. The method of claim 3, wherein the first front end component comprises an amplifier and the second front end component comprises a mixer.

5. The method of claim 1, further comprising reducing the power consumption if the environmental noise power level is at least a factor times the receiver-generated noise power.

6. The method of claim 5, further comprising thereafter if the environmental noise level is within a threshold amount of the receiver-generated noise, increasing power consumption of the at least one front end component of the receiver.

7. The method of claim 1, further comprising maintaining a maximum power mode of the receiver if the environmental noise level is not substantially greater than the receiver-generated noise.

8. The method of claim 7, wherein in the maximum power mode, each of a plurality of front end components of the receiver has all of multiple parallel stages enabled.

9. The method of claim 1, wherein the receiver-generated noise levels are stored in the table during fabrication of the receiver.

10. The method of claim 1, further comprising configuring the receiver to operate in a reduced power consumption mode for a majority of environmental conditions.

11. The method of claim 1, further comprising operating the receiver at a first power consumption level in a laboratory environment and operating the receiver at a second power consumption level in a non-laboratory environment, the second power consumption level lower than the first power consumption level.

12. An apparatus comprising:

a receiver having an analog front end including a signal path to receive and downconvert a radio frequency (RF) signal to a second frequency signal, the analog front end including;

a low noise amplifier (LNA) having a first plurality of parallel paths to receive and amplify the RF signal;

a mixer coupled to the LNA to downconvert the RF signal to the second frequency signal, the mixer having a second plurality of parallel paths;

a demodulator coupled to the analog front end to receive the second frequency signal and to demodulate the second frequency signal; and

a controller to control a power consumption level of the receiver based at least in part on an environmental noise level of an environment in which the receiver is located.

13. The apparatus of claim 12, further comprising a noise estimator coupled to the signal path to estimate the environmental noise level based on the RF signal.

14. The apparatus of claim 13, wherein the noise estimator includes a coordinate rotation digital computer (CORDIC) engine to calculate a magnitude and a phase from the second frequency signal and to generate the environmental noise level based on a variation in at least one of the magnitude and the phase.

15. The apparatus of claim 14, wherein the controller is to estimate an input-referred environmental noise level based on the environmental noise level and a gain of the analog front end, and to compare the estimated input-referred environmental noise level to a receiver-generated noise level obtained from a table stored in the receiver.

16. The apparatus of claim 12, wherein the controller is to reduce the power consumption level of at least one of the LNA and the mixer from a maximum power mode level if the environmental noise level is substantially greater than receiver-generated noise at the maximum power mode level.

17. The apparatus of claim 16, wherein the controller is to increase the power consumption level of at least one of the LNA and the mixer if the environmental noise level is thereafter within a threshold amount of the receiver-generated noise.

18. The apparatus of claim 16, wherein the controller is to determine the environmental noise level based on amplitude jitter present in the second frequency signal in an FM mode and to estimate the environmental noise level based on phase jitter present in the second frequency signal in an AM mode.

19. The apparatus of claim 12, wherein the controller is to control the power consumption level further based on a received signal strength indication.

20. A system comprising:

a receiver having an analog front end including a signal path to receive and downconvert a radio frequency (RF) signal to a second frequency signal, the analog front end including;

an environmental noise detector to estimate an environmental noise level of an environment in which the receiver is located based on a first signal metric of the RF signal;

a table to store characterization data of the receiver, the characterization data including a receiver-generated noise level associated with each of a plurality of power levels at which the receiver can operate; and

a power controller to control a power consumption level of the receiver based on the environmental noise level and the receiver-generated noise level.

21. The system of claim 20, wherein the power controller is to send control signals to at least one component of the analog front end to disable at least one of a plurality of parallel stages of a first front end component of the receiver.

22. The system of claim 20, wherein the power controller is to enable the receiver to operate at a first power consumption level in a laboratory environment and at a second power consumption level in a non-laboratory environment, the second power consumption level lower than the first power consumption level.

23. The system of claim 20, further comprising a noise estimator coupled to the signal path to estimate the environmental noise level based on the RF signal, and including a coordinate rotation digital computer (CORDIC) engine to calculate a magnitude and a phase from the second frequency signal and to estimate the environmental noise level based on a variation in at least one of the magnitude and phase.

24. The system of claim 23, wherein the power controller is to estimate an input-referred environmental noise level based on the environmental noise level and a gain of the analog front end, and to compare the estimated input-referred environmental noise level to a receiver-generated noise level obtained from the table.

25. An article comprising a machine-accessible storage medium including instructions that when executed cause a system to:

receive and process a digital communication signal in the system;

determine a signal-to-noise ratio (SNR) based on the digital communication signal, and if the SNR is greater than a threshold level, reduce power consumption of at least one analog front end component of the system; and

determine an environmental noise level corresponding to environmental noise present in an environment in which the system is located, and if the environmental noise level is substantially greater than receiver-generated noise, reduce power consumption of the at least one analog front end component, wherein a desired channel is of an analog modulation.

26. The article of claim 25, wherein when the SNR is at least at the threshold level, at least a minimum desired bit error rate (BER) is obtained.