Power-efficient multi-antenna wireless device

• US 20050250452A1
• Filed: 01/31/2005
• Published: 11/10/2005
• Est. Priority Date: 05/07/2004
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Walton, Jay Rodney, Wallace, Mark S., Antonio, Franklin Peter, Narayan, Sriram
• Granted Patent: US 8,036,710 B2
• Time in Patent Office: Days
• US Class Current: 455/63.400
• CPC Class Codes: H04W 52/0274 by switching on or off the equipment or parts thereof
• CPC Class Codes: H04W 52/029 reducing the clock frequency of the controller
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A power-efficient wireless device is equipped with multiple (N) antennas. Each antenna is associated with a transmitter unit and a receiver unit. The wireless device also has processing units used to perform various digital processing tasks. The transmitter units, receiver units, and processing units may be selectively enabled or disabled. In an idle state, the wireless device may enable only a subset (e.g., one) of the N receiver units and one or few processing units for signal detection and acquisition. For active communication, the wireless device may enable N_tx transmitter units for data transmission and/or N_rx receiver units for data reception, where 1≧N_tx≧N and 1≧N_rx≧N. The enabled processing units may also be clocked at a lower frequency whenever data is transmitted or received at a data rate lower than the highest data rate. The wireless device may go to sleep whenever possible to conserve power.

Claims

1. A multi-antenna wireless device comprising:

a plurality of (N) transmitter units operatively coupled to a plurality of antennas, one transmitter unit for each set of at least one antenna from among the plurality of antennas, each transmitter unit operable to process a respective input signal and provide an output signal; and

a controller to selectively enable or disable at least one of the N transmitter units.

2. The wireless device of claim 1, wherein the controller selects one of a plurality of operating modes for the wireless device, each operating mode utilizing a different combination of the N transmitter units.

3. The wireless device of claim 2, wherein the controller enables one of the N transmitter units and disables remaining ones of the N transmitter units if a mode supporting transmission of a single output signal is selected, and wherein the enabled transmitter unit generates the single output signal.

4. The wireless device of claim 2, wherein the controller enables multiple ones of the N transmitter units and disables remaining ones, if any, of the N transmitter units if a mode supporting transmission of multiple output signals is selected, and wherein the enabled transmitter units generate the multiple output signals.

5. The wireless device of claim 1, wherein the controller disables the N transmitter units when data is not transmitted.

6. The wireless device of claim 1, further comprising:

a power source operative to cut off power to each transmitter unit that is disabled.

7. An apparatus comprising:

a plurality of (N) transmitter units operatively coupled to a plurality of antennas, one transmitter unit for each set of at least one antenna from among the plurality of antennas, each transmitter unit operable to process a respective input signal and provide an output signal; and

means for selectively enabling or disabling at least one of the N transmitter units.

8. The apparatus of claim 7, wherein the means for selectively enabling or disabling comprises means for enabling one of the N transmitter units and disabling remaining ones of the N transmitter units if a mode supporting transmission of a single output signal is selected, and wherein the enabled transmitter unit generates the single output signal.

9. The apparatus of claim 7, wherein the means for selectively enabling or disabling comprises

means for enabling multiple ones of the N transmitter units and disabling remaining ones, if any, of the N transmitter units if a mode supporting transmission of multiple output signals is selected, and wherein the enabled transmitter units generate the multiple output signals.

10. The apparatus of claim 7, further comprising:

means for cutting off power to each transmitter unit that is disabled.

11. A multi-antenna wireless device comprising:

a plurality of (N) receiver units operatively coupled to a plurality of antennas, one receiver unit for each set of at least one antenna from among the plurality of antennas, each receiver unit operable to process a respective input signal and provide an output signal; and

a controller to selectively enable or disable at least one of the N receiver units.

12. The wireless device of claim 11, wherein the controller selects one of a plurality of operating modes for the wireless device, each operating mode utilizing a different combination of the N receiver units.

13. The wireless device of claim 12, wherein the controller enables one of the N receiver units and disables remaining ones of the N receiver units if a mode supporting reception of a single input signal is selected, and wherein the enabled receiver unit processes the single input signal.

14. The wireless device of claim 12, wherein the controller enables multiple ones of the N receiver units and disables remaining ones, if any, of the N receiver units if a mode supporting reception of multiple input signals is selected, and wherein the enabled receiver units process the multiple input signals.

15. The wireless device of claim 11, wherein the controller disables the N receiver units when data is not received.

16. The wireless device of claim 11, further comprising:

a power source operative to cut off power to each receiver unit that is disabled.

17. A multi-antenna wireless device comprising:

at least one processing unit, each processing unit operable to perform designated processing for data transmission or reception via at least one of a plurality of antennas, each processing unit being enabled if the designated processing by the processing unit is used for data transmission or reception and disabled otherwise; and

a controller to enable or disable each of the at least one processing unit.

18. The wireless device of claim 17, wherein the at least one processing unit comprises

a detection and acquisition unit to perform signal detection and acquisition, wherein the detection and acquisition unit is enabled if the wireless device is monitoring for signals from other entities and disabled otherwise.

19. The wireless device of claim 17, wherein the at least one processing unit comprises

a spatial processor to perform spatial processing for data transmission and reception, wherein the spatial processor is enabled to perform spatial processing if multiple ones of the plurality of antennas are used for data transmission or reception and disabled otherwise.

20. The wireless device of claim 17, wherein the at least one processing unit comprises

a data processor to process data for transmission and reception, wherein the data processor is enabled if data processing is performed for transmission or reception and disabled otherwise.

21. The wireless device of claim 17, wherein the at least one processing unit comprises

a modulator to perform modulation for data transmission, wherein the modulator is enabled if data is being transmitted and disabled otherwise.

22. The wireless device of claim 17, wherein the at least one processing unit comprises

a demodulator to perform demodulation for data reception, wherein the demodulator is enabled if data is being received and disabled otherwise.

23. The wireless device of claim 17, further comprising:

a power source operative to cut off power to each processing unit that is disabled.

24. The wireless device of claim 17, further comprising:

a clock generator to generate clocks for processing units that are enabled and to disable clocks to processing units that are disabled.

25. The wireless device of claim 17, further comprising:

a clock generator to generate clocks for the at least one processing unit, the clocks having a variable frequency determined by data rates used for data transmission or reception.

26. The wireless device of claim 17, wherein the controller disables the at least one processing unit when data is not transmitted or received.