SYSTEMS AND METHODS FOR CONSERVING THE POWER SUPPLY OF A COMMUNICATIONS DEVICE

• US 20090046789A1
• Filed: 08/13/2007
• Published: 02/19/2009
• Est. Priority Date: 08/13/2007
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Imamura, Kimihiko, Xu, Shugong
• Granted Patent: US 7,995,661 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0241 where no transmission is received, e.g. out of range of the transmitter
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for conserving the power supply of an Orthogonal Frequency Division Multiplexing (OFDM) communications device is described. The location of a bit of information within one of a plurality of symbols is obtained. A sleep mode is entered into. The one symbol that includes the bit of information is monitored. A return to the sleep mode is executed.

Claims

1. A method for conserving the power supply of an orthogonal frequency Division Multiplexing (OFDM) communications device, comprising:

obtaining the location of a bit of information within one of a plurality of symbols;

entering into a sleep mode;

monitoring the one symbol that includes the bit of information; and

returning to the sleep mode.

2. The method of claim 1, wherein the bit of information comprises an acknowledgment/non-acknowledgment (ACK/NAK) bit.

3. The method of claim 1, wherein the plurality of symbols comprises Orthogonal Frequency Division Multiplexing (OFDM) symbols.

4. The method of claim 1, further comprising determining if a silence period on a downlink of the communications device has started.

5. The method of claim 1, further comprising receiving a time period information to enable monitoring each of the plurality of symbols.

6. The method of claim 5, further comprising remaining in an awake mode to monitor each of the plurality of symbols based on the time period information.

7. The method of claim 5, wherein the time period is less than 160 milliseconds.

8. The method of claim 1, wherein the location of a bit of information within one of a plurality of symbols is transmitted by an Evolved NodeB to the OFDM communications device.

9. A communications device in an Orthogonal Frequency Division Multiplexing (OFDM) system, wherein the communications device is configured to conserve its power supply, the communications device comprising:

a processor;

memory in electronic communication with the processor;

instructions stored in the memory, the instructions being executable to;

obtain the location of a bit of information within one of a plurality of symbols;

enter into a sleep mode;

monitor the one symbol that includes the bit of information; and

return to the sleep mode.

10. The communications device of claim 9, wherein the bit of information comprises and acknowledgment/non-acknowledgment (ACK/NAK) bit.

11. The communications device of claim 9, wherein the plurality of symbols comprises Orthogonal Frequency Division Multiplexing (OFDM) symbols.

12. The communications device of claim 9, wherein the instructions are further executable to determine if a silence period on a downlink of the communications device has started.

13. The communications device of claim 9, wherein the instructions are further executable to receive a time period information to enable monitoring each of the plurality of symbols.

14. The communications device of claim 13, wherein the instructions are further executable to remain in an awake mode to monitor each of the plurality of symbols based on the time period information.

15. The communications device of claim 13, wherein the time period is less than 160 milliseconds.

16. The communications device of claim 9, wherein the location of a bit of information within one of a plurality of symbols is transmitted by an Evolved NodeB to the communications device.

17. A base station that is configured to inform a communications device the location of a bit of information, the base station comprising:

a processor;

memory in electronic communication with the processor;

instructions stored in the memory, the instructions being executable to;

provide n Orthogonal Frequency Division Multiplexing (OFDM) symbols to send an acknowledgment/non-acknowledgment (ACK/NAK) bit per subframe, wherein n is a natural number;

insert the ACK/NAK bit for the communications device into one of the OFDM symbols; and

inform the communications device which OFDM symbol includes the ACK/NAK bit.

18. The base station of claim 17, wherein Radio Resource Control (RRC) signaling is used to inform the communications device which OFDM symbol includes the ACK/NAK bit.

19. The base station of claim 17, wherein the OFDM symbols transmit a Physical Downlink Control Channel (PDCCH), a Physical Hybrid Automatic Request Indicator Channel (PHICH) and a Physical Control Format Indicator Channel (PCFICH).

20. A computer-readable medium comprising executable instructions for:

obtaining the location of a bit of information within one of a plurality of Orthogonal Frequency Division Multiplexing (OFDM) symbols;

entering into a sleep mode;

monitoring the one symbol that includes the bit of information; and

returning to the sleep mode.