Power management of radio transceiver elements

• US 20040029620A1
• Filed: 10/22/2002
• Published: 02/12/2004
• Est. Priority Date: 08/12/2002
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Karaoguz, Jeyhan
• Granted Patent: US 7,512,423 B2
• Time in Patent Office: Days
• US Class Current: 455/574
• CPC Class Codes: H04B 1/1615 Switching on; Switching off, e.g. remotely battery saving circuits associated with selective call operation H04W52/00; details of power consumption reduction in a PLL, H03L7/0802, H03L7/14, H03L2207/08, H03L2207/18; muting amplifiers by gain control see H03G3/34
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: H04W 52/0283 with sequential power up or power down of successive circuit blocks, e.g. switching on the local oscillator before RF or mixer stages
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A radio receiver includes a power control module for selectively powering down and powering up radio receiver elements in between known communication periods according to one aspect of the present invention. According to a second aspect of the invention, the radio receiver operates in a low power mode of operation and periodically “sniffs” to determine whether an access point has messages or communication signals to transmit to it.

Claims

1. A method for saving power in a radio receiver, comprising:

determining a receiver inactivity time wherein the receiver inactivity time is a time period between received radio frequency (RF) transmissions;

determining a list of elements of the radio receiver that can be powered down and back within the receiver inactivity time to reduce power consumption;

establishing, based upon the determined inactivity time, a power reduction mode for at least one element of the radio receiver;

determining a restoration time for the at least one element; and

powering the at least one element of the radio receiver to an operational mode at the restoration time wherein the at least one element has reached a steady state of operation by the expiration of the receiver inactivity time.

2. The method of claim 1 wherein the receiver inactivity time is based upon a number considerations including known and defined communication periods, a number of communication beacons, or a known amount of time until an allocated time slot in a time divided communication system.

3. The method of claim 1 wherein the at least one element comprises at least one of a RF front end section, a low noise amplifier, a local oscillator crystal, a local oscillator crystal amplifier, a local oscillator phase-locked-loop module, a local oscillator clock distribution tree, a filtering module, a physical baseband processor module, an analog-to-digital conversion module, a first portion of a medium access control (MAC) processor, or a second portion of the MAC processor.

4. The method of claim 1 wherein the restoration time is approximately equal to the determined receiver inactivity time minus an element wake up time for the at least one element.

5. A method for saving power in a radio receiver, comprising:

determining a radio receiver element inactivity time for at least one radio receiver element;

establishing, based upon the determined inactivity time, a power reduction mode for the at least one radio receiver element;

determining a restoration time for the at least one radio receiver element; and

powering the at least one radio receiver element to an operational mode at the restoration time.

6. The method of claim 5 wherein the inactivity time is based upon a number of considerations including known and defined communication periods, a number of communication beacons, or a known amount of time until an allocated time slot in a time divided communication system.

7. The method of claim 5 wherein the restoration time is approximately equal to the determined radio receiver inactivity time minus an element wake up time for the at least one radio receiver element.

8. The method of claim 5 wherein the at least one radio receiver element comprises at least one of a RF front end section, a low noise amplifier, a local oscillator crystal, a local oscillator crystal amplifier, a local oscillator phase-locked-loop module, a local oscillator clock distribution tree, a filtering module, a physical baseband processor module, an analog-to-digital conversion module, a first portion of a medium access control (MAC) processor, or a second portion of the MAC processor.

9. The method of claim 5 further comprising determining a radio receiver element inactivity time for a plurality of radio receiver elements.

10. The method of claim 9 further comprising establishing, based upon the determined inactivity time, a power reduction mode for the plurality of radio receiver elements.

11. The method of claim 10 further comprising determining a restoration time for the plurality of radio receiver elements.

12. The method of claim 11 further comprising powering the plurality of radio receiver elements to an operational mode at the restoration time of each of the plurality of radio receiver elements.

13. The method of claim 12 wherein the inactivity time for each of the plurality of radio receiver elements is based upon a number of communication beacons.

14. A method for saving power in a radio receiver, comprising:

determining a radio receiver element inactivity time for at least one radio receiver element;

determining a restoration time for the at least one radio receiver element;

determining a wake up time for the at least one radio receiver element;

determining whether to place the at least one radio receiver element into a power reduction mode;

determining what type of a plurality of types of power reduction modes should be selected for the at least one radio receiver element if it is to be placed into the power reduction mode;

placing the at least one radio receiver element into the selected power reduction mode; and

powering the at least one radio receiver element to an operational mode at the restoration time.

15. The method of claim 14 wherein the inactivity time is based upon a number considerations including known and defined communication periods, a number of communication beacons, or a known amount of time until an allocated time slot in a time divided communication system.

16. The method of claim 14 wherein the restoration time is approximately equal to the determined inactivity time minus an element wake up time for the at least one radio receiver element.

17. The method of claim 14 wherein the at least one radio receiver element comprises at least one of a RF front end section, a low noise amplifier, a local oscillator crystal, a local oscillator crystal amplifier, a local oscillator phase-locked-loop module, a local oscillator clock distribution tree, a filtering module, a physical baseband processor module, an analog-to-digital conversion module, a first portion of a medium access control (MAC) processor, or a second portion of the MAC processor.

18. The method of claim 14 further comprising determining a radio receiver element inactivity time for each of a plurality of radio receiver elements.

19. The method of claim 14 further including establishing a power reduction mode for each of the plurality of radio receiver elements based upon the determined inactivity time.

20. The method of claim 19 further comprising determining a restoration time for each of the plurality of radio receiver elements.

21. The method of claim 20 further comprising powering each of the plurality of radio receiver elements to an operational mode at the restoration time determined for each of the plurality of radio receiver elements.

22. The method of claim 21 wherein the inactivity time for each of the plurality of radio receiver elements is based upon a number of communication beacons.

23. A method for saving power in a radio receiver, comprising

for a first radio receiver element:

determining a first radio receiver element inactivity time;

determining a first restoration time;

determining a first wake up time;

determining whether to place the first radio receiver element into a power reduction mode; and

determining what type of a plurality of types of power reduction modes should be selected for the first radio receiver element;

for a second radio receiver element;

determining a second radio receiver element inactivity time;

determining a second restoration time;

determining a second wake up time;

determining whether to place the second radio receiver element into a power reduction mode; and

determining what type of a plurality of types of power reduction modes should be selected for the second radio receiver element;

placing the first radio receiver element into a first selected power reduction mode;

placing the second radio receiver element into a second selected power reduction mode;

powering the first radio receiver element to an operational mode at the first restoration time for the first radio receiver element; and

powering the second radio receiver element to an operational mode at the second restoration time for the second radio receiver element.

24. The method of claim 23 wherein the first selected power reduction mode is a partial power reduction mode.

25. The method of claim 23 wherein the second selected power reduction mode is a full power reduction mode.

26. A method for reducing power consumption in a radio transceiver, comprising:

determining an inactivity time;

based upon the inactivity time being less than or equal to a first value, determining to not power down any radio transceiver elements;

based upon the inactivity time being greater than the first value and less than or equal to a second value, determining to power down a first group of radio transceiver elements; and

based upon the inactivity time being greater than the second value and less than or equal to a third value, determining to power down a second group of radio transceiver elements.

27. The method of claim 26 further comprising, based upon the inactivity time being greater than the third value and less than or equal to a fourth value, determining to power down a third group of radio transceiver elements.

28. The method of claim 26 further comprising, based upon the inactivity time being greater than the fourth value and less than or equal to a fifth value, determining to power down a fourth group of radio transceiver elements.

29. The method of claim 26 wherein the determining step includes determining whether the inactivity time is great enough to allow radio receiver elements to be powered down and then powered back on.

30. The method of claim 29 wherein the determining step includes determining whether the inactivity time is great enough to allow the radio receiver elements to be powered down and then powered back on in a manner that saves power.

31. The method of claim 30 wherein the determining step includes determining an approximate power savings for a period in which the radio receiver elements will be powered down and comparing the power savings value with an approximate amount of power required to power the element down and then power the element back on.

32. A method within a radio transceiver integrated circuit for reducing power consumption, comprising:

determining a receiver inactivity time;

if the receiver inactivity time is less than a first value, powering down no elements;

if the receiver inactivity time is greater than a second value, powering down all elements;

if the receiver inactivity time is within a first range of values between the first and second values, powering down a first group of elements, the first group of elements being a subset of a group of all elements; and

determining a restoration time for each powered down element.

33. The method of claim 32 further including powering down a second group of elements if the receiver inactivity time is within a second range of values between the first and second values.

34. The method of claim 32 further including powering down a third group of elements if the receiver inactivity time is within a third range of values between the first and second values.

35. The method of claim 32 further including, for each element that has been powered down, powering the element back on at its corresponding restoration time.

36. The method of claim 32 further including grouping elements according to restoration times being within specified ranges of values and powering the elements according to the groupings of restoration times.

37. The method of claim 32 wherein the radio receiver integrated circuit powers on a group of powered down radio receiver elements and attempts to determine whether there are any transmissions intended for it.

38. The method of claim 37 further including transmitting to at least one external radio transceiver to determine if it has any pending messages, pages, or calls being temporarily stored for delivery to the radio transceiver integrated circuit.

39. A radio receiver integrated circuit, comprising:

analog front end operably coupled to receive an inbound radio frequency (RF) signal and a local oscillation to produce there from an analog baseband signal;

baseband processing module operably coupled to produce data from the analog baseband signal;

local oscillator operably coupled to produce the local oscillation; and

power control module operably coupled to the analog front end, the baseband processing module, and the local oscillation, wherein the power control module enables power reduction of the analog front end, the baseband processing module, and the local oscillator based on radio receiver inactivity time and restoration time of the analog front end, the baseband processing module, and the local oscillator.

40. The radio receiver integrated circuit of claim 39 wherein the power control module determines to power down a first group of elements whenever the radio receiver inactivity time is less than or equal to a first value.

41. The radio receiver integrated circuit of claim 40 wherein the power control module determines to power down a second group of elements whenever the radio receiver inactivity time is greater than the first value and is less than or equal to a second value.

42. The radio receiver integrated circuit of claim 41 wherein the power control module determines to power down a third group of elements whenever the radio receiver inactivity time is greater than the second value and is less than or equal to a third value.

43. The radio receiver integrated circuit of claim 42 wherein the power control module determines to power down a fourth group of elements whenever the radio receiver inactivity time is greater than the third value and is less than or equal to a fourth value.

44. The radio receiver integrated circuit of claim 39 wherein the radio receiver inactivity time is approximately in the range of 5 microseconds to 300 milliseconds.

45. The radio receiver integrated circuit of claim 39 wherein the power control module determines to power up a fifth group of elements, wherein each element of the fifth group of elements has a restore time value within a first specified range of restore time values wherein the fifth group of elements comprises a list of elements that is not necessarily different from any one of the first four groups of elements.

46. The radio receiver integrated circuit of claim 39 wherein the power control module determines to power up a sixth group of elements, wherein each element of the sixth group of elements has a restore time value within a second specified range of restore time values wherein the sixth group of elements comprises a list of elements that is not necessarily different from any one of the first four groups of elements.

47. A radio receiver integrated circuit, comprising:

analog front end operably coupled to receive an inbound radio frequency (RF) signal and a local oscillation to produce an analog baseband signal;

baseband processing module operably coupled to produce data from the analog baseband signal;

local oscillator means operably coupled to produce the local oscillation; and

power control means operably coupled to the analog front end, the baseband processing module, and the local oscillation, wherein the power control means enables power reduction and restoration of a receiver element including elements formed in a receiver analog front end, a baseband processing module, and a local oscillator, all based on radio receiver inactivity time and restoration time of the receiver elements.