Slotted idle mode for dual mode subscriber stations

• US 6,434,376 B1
• Filed: 02/12/1999
• Issued: 08/13/2002
• Est. Priority Date: 02/12/1999
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Black, Peter J.
• Primary Examiner(s): Maung, Nay
• Assistant Examiner(s): CONTEE, JOY KIMBERLY
• Application Number:
  US09/248,961
• Time in Patent Office: 1,278 Days
• Field of Search: 455/574, 455/343, 455/38.3, 455/422, 455/425, 455/575, 455/550, 375/340, 375/224, 375/346, 375/347, 375/365, 375/366
• US Class Current: 455/343.3
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• 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 system and method for reducing average idle current in a telecommunications system handset by decreasing the power when demodulation of the incoming signal and decoding of FOCC data stream is unnecessary is provided. The system and method supplant the need to decode all five repeated FOCC data words. The system performs various testing on each of the five data words as they are received. If the data words satisfy particular conditions, such as comprising control filler words or match one another based on the result of testing, no further processing of words occurs until the next sync is received and sleep mode is initiated. According to a further feature, the system may erase the sync/dotting sequence if and only if the prior sync word is successfully decoded. The system and method support both A and B slotting and power down components of the handset, such as RF circuitry and/or data sync timers.

Claims

1. A method for reducing average idle current in a handset receiving forward control channel data, said forward control channel data comprising a plurality of data words, each forward control channel word comprising a dotting sequence and a sync word, said method comprising the steps of:

receiving a first word of the forward control channel data;

determining whether the first word of the forward control channel data comprises a control filler message;

powering down a predetermined component of the handset for a predetermined period of time based on the results of said determining step;

receiving a second word of the forward control channel data;

judging whether the first word and second word of the forward control channel are identical;

performing a decoding operation on the two forward control channel data words;

erasing said dotting sequence and sync word of a selected forward control channel word if and only if a prior sync word of a prior forward control channel word is successfully decoded; and

powering down a predetermined component of the handset for a predetermined period of time based on the results of said judging step and said performing step.

2. The method of claim 1, further comprising the steps of:

receiving a third forward control channel data word;

evaluating whether the three forward control channel data words are identical; and

powering down a predetermined component of the handset for a predetermined period of time based on the results of said evaluating step.

4. The method of claim 1, further comprising the step of:

storing each data word determined to comprise a control filler message.

5. The method of claim 1, further comprising the step of:

detecting a control filler word using a predetermined bit mask.

6. The method of claim 1, further comprising the steps of:

providing for the bypassing of said determining step under predetermined conditions; and

providing for the bypassing of said judging step under predetermined conditions.

3. A method for reducing average idle current in a handset receiving forward control channel data, said forward control channel data comprising a plurality of data words, said method comprising the steps of:

receiving a first word of the forward control channel data;

determining whether the first word of the forward control channel data comprises a control filler message;

powering down a predetermined component of the handset for a first predetermined period of time based on the results of said determining step;

receiving a second word of the forward control channel data;

judging whether the first word and second word are identical;

performing a decoding operation on the two forward control channel data words;

powering down the predetermined component of the handset for a second predetermined period of time based on the results of said judging step and said performing step;

receiving a third forward control channel data word;

evaluating whether the three forward control channel data words are identical; and

powering down the predetermined component of the handset for a third predetermined period of time based on the results of said evaluating step;

receiving a fourth forward control channel data word;

ascertaining whether three of the four forward control channel data words are identical; and

powering down the predetermined component of the handset for a fourth predetermined period of time based on the results of said ascertaining step.

7. A method for reducing average idle current in a receiver of forward control channel data, said forward control channel data comprising a plurality of data words, each data word comprising a dotting sequence and a sync word, said method comprising the steps of:

receiving an initial data word;

determining whether said initial data word sufficiently matches a predetermined filler word;

erasing said dotting sequence and sync word of a selected data word if and only if a prior sync word of a prior data word is successfully decoded; and

reducing electrical flow to a predetermined component associated with said receiver for a predetermined period of time when said initial data word sufficiently matches said predetermined filler word.

8. The method of claim 7, further comprising the steps of:

receiving a second data word;

judging whether the initial data word and the second data word are identical;

performing a decoding validity assessment on the initial data word and the second data word; and

reducing electrical flow to a predetermined component associated with said receiver for a predetermined period of time when said initial data word and said second data word are identical and the initial data word and second data word have been validly decoded.

9. The method of claim 8, further comprising the steps of:

receiving a third data word;

evaluating whether the three received data words are identical; and

reducing electrical flow to a predetermined component associated with said receiver for a predetermined period of time when said three data words are identical.

10. The method of claim 7, wherein said determining step comprises detecting the predetermined filler word by comparing said initial data word with a predetermined bit mask.

11. The method of claim 9, further comprising the steps of:

receiving a fourth data word;

ascertaining whether three of the four received data words are identical; and

reducing electrical flow to a predetermined component associated with said receiver for a predetermined period of time when three of the four received data words are identical.

12. The method of claim 7, further comprising the step of:

storing each message determined to be a control filler message.

13. The method of claim 7, further comprising the step of:

providing for the bypassing of said determining step under predetermined conditions.

14. The method of claim 8, further comprising the step of:

providing for the bypassing of said judging step under predetermined conditions.

15. A method for reducing average idle current in a receiver of forward control channel data, said forward control channel data comprising a plurality of data words characterized by a dotting sequence and a sync word, said method comprising the steps of:

receiving an initial data word and a second data word;

judging whether the initial data word and the second data word are identical;

providing for the bypassing of said judging step under predetermined conditions;

performing a decoding validity assessment on the initial data word and the second data word;

erasing an associated dotting sequence and sync word of a data word if and only if a prior sync word of a prior data word is successfully decoded; and

reducing electrical flow to a predetermined component associated with said receiver for a predetermined period of time when said initial data word and said second data word are identical and the initial data word and second data word have been validly decoded.

16. The method of claim 15, further comprising the steps of:

determining whether said initial data word sufficiently matches a predetermined filler word; and

reducing electrical flow to the predetermined component associated with said receiver for a second predetermined period of time when said initial data word sufficiently matches said predetermined filler word;

wherein said determining step and step of reducing the electrical flow for a second predetermined period occur prior to receiving said second data word.

17. The method of claim 16, further comprising the steps of:

receiving a third data word;

evaluating whether the three received data words are identical; and

powering down a predetermined component of the handset for a predetermined period of time when said three data words are identical.

18. The method of claim 16, wherein said determining step comprises detecting the predetermined filler word by comparing said initial data word with a predetermined bit mask.

19. The method of claim 17, further comprising the steps of:

receiving a fourth data word;

ascertaining whether three of the four received data words are identical; and

powering down a predetermined component associated with the receiver for a predetermined period of time based on the results of said ascertaining step.

20. The method of claim 16, further comprising the step of:

storing each message determined to be a control filler message.

21. The method of claim 16, further comprising the step of:

providing for the bypassing of said determining step under predetermined conditions.

22. A method for reducing average idle current in a receiver of forward control channel data words, wherein each data word received comprises a dotting sequence and a sync word, said method comprising the steps of:

receiving a plurality of forward control channel data words; and

erasing said dotting sequence and sync word of a selected data word if and only if a prior sync word of a prior data word is successfully decoded.

23. A telecommunications system for receiving and decoding forward control channel data, said forward control channel data comprising a plurality of data words, said system comprising:

means for receiving a first data word;

means for determining whether said initial data word sufficiently matches a predetermined filler word;

means for reducing electrical flow to a predetermined component within the telecommunications system for a first predetermined period of time when said initial data word sufficiently matches said predetermined filler word;

means for receiving a second data word;

means for judging whether the first data word and the second data word are identical;

means for performing a decoding validity assessment on the first data word and the second data word;

means for reducing electrical flow to the predetermined component associated with said receiver for a second predetermined period of time when said first data word and said second data word are identical and the first data word and second data word have been validly decoded

means for receiving a third data word;

means for evaluating whether the three received data words are identical;

means for reducing electrical flow to the predetermined component of the telecommunications system for a third predetermined period of time when said three data words are identical

means for receiving a fourth data word;

means for ascertaining whether three of the four received data words are identical; and

means for powering down the predetermined component associated with the telecommunications system for a fourth predetermined period of time based on whether three of the four received data words are identical.

24. The telecommunications system of claim 23, wherein said determining means comprises means for detecting the predetermined filler word by comparing said initial data word with a predetermined bit mask.

25. The telecommunications system of claim 23, further comprising means for storing any initial data word determined to be a control filler message.

26. The telecommunications system of claim 23, wherein each data word received comprises a dotting sequence and a sync word, said telecommunications system further comprising:

means for erasing said dotting sequence and sync word of a selected data word if and only if a prior sync word of a prior data word is successfully decoded.

27. The telecommunications system of claim 23, further comprising:

means for providing for the bypassing of said determining step under predetermined conditions.

28. The telecommunications system of claim 23, further comprising:

means for providing for the bypassing of said judging step under predetermined conditions.