Method and apparatus for reducing power consumption of a communication device

• US 6,289,228 B1
• Filed: 07/20/1999
• Issued: 09/11/2001
• Est. Priority Date: 07/20/1999
• Status: Expired due to Fees

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Corke, Robert J., Luz, Yehuda, Prysby, Daniel G., Rotstein, Ron
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US09/357,494
• Time in Patent Office: 784 Days
• Field of Search: 455/343, 455/574, 455/38.3, 340/7.32, 340/7.33, 340/7.36, 370/342
• US Class Current: 455/574
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method of reducing power consumption in a communication device includes a step of acquiring a signal on a common pilot channel of a radio communication system. A next step includes detecting predetermined bits in the signal on the common pilot channel indicating activity on paging channels of the radio communication system. When no paging channel activity is indicated in the second step, a last step includes powering down portions of the electrical circuitry of the communication device so as to reduce power consumption, and when paging channel activity is indicated in the second step, a next step includes powering up portions of the electrical circuitry of the communication device such that those paging channels indicating activity are monitored by the communication device.

Claims

1. A method of reducing power consumption in a communication device having electrical circuitry, the method comprising the steps of:

acquiring a signal on a common pilot channel of a radio communication system while the communication device is in a sleep mode;

detecting n predetermined bits punctured into a Walsh code of 0 comprising the signal on the common pilot channel, the n bits indicating activity on particular paging channels of the radio communication system; and

when no activity is indicated in the detecting step, powering down portions of the electrical circuitry of the communication device so as to reduce power consumption, and

when activity is indicated in the detecting step, powering up portions of the electrical circuitry of the communication device, and monitoring those paging channels indicating activity.

2. The method of claim 1, wherein the n bits of the detecting step are located in predetermined locations punctuating a paging slot such that degradation in a channel estimate and searcher results derived from the pilot channel are minimized.

3. The method of claim 1, wherein the powering up step includes a subsequent substep of powering down the portions of the electrical circuitry of the communication device after those paging channels indicating activity have been monitored by the communication device and any calls received by the radio communication device have been completed.

4. The method of claim 3, wherein the predetermined bits of the detecting step are located in predetermined locations of a first slot of data, and wherein after the powering down substep, further comprising the substep of maintaining the power off of the portions of the electrical circuitry of the communication device until a next slot following the first slot, wherein at the next slot continuing at the acquiring step.

5. The method of claim 1, wherein the monitoring substep of the powering up step includes substeps of acquiring a synchronization channel of the radio communication system so as to synchronize timing of the communication device to the radio communication system, and acquiring and reading those paging channels indicating a ctivity in the detecting step.

6. The method of claim 1, further comprising a step of receiving a second set of predetermined bits so as to provide an estimate of channel gain.

7. The method of claim 1, wherein the radio communication system of the detecting step is at least one of a personal digital cellular (PDC) system, a Japan digital cellular (JDC) system, a code division multiple access (CDMA) system, a direct sequence code division multiple access (DS-CDMA) system, a groupe speciale mobile (GSM) system, and a slotted paging mode groupe speciale mobile (GSM-DRX) system.

8. A method of reducing power consumption in a communication device having analog receiver circuitry, digital receiver circuitry including searcher circuitry in a portion thereof, and a digital signal processor including call processor circuitry in a portion thereof, the method comprising the steps of:

providing analog receiver circuitry coupled to digital receiver circuitry including searcher circuitry in a portion thereof and a digital signal processor including call processor circuitry in a portion thereof, in a powered off sleep mode;

powering on the analog receiver circuitry, the searcher circuitry, and the call processor circuitry such that the analog receiver circuitry is operable to receive signals from a radio communication system;

sensing a signal of a common pilot channel through the analog receiver circuitry and coupled to the searcher circuitry;

processing the signal from the sensing step by the call processor circuitry so as to retrieve predetermined bits indicate activity on paging channels of the radio communication system; and

when no activity is indicated in the processing step, powering down the analog receiver circuitry, searcher circuitry, and call processor circuitry of the communication device so as to reduce power consumption, and

when activity is indicated in the processing step, powering up the digital receiver circuitry and the digital signal processor such that those paging channels indicating activity are monitored by the communication device.

9. The method of claim 8, wherein the predetermined bits of the processing step include n bits punctuating a Walsh code of 0 comprising the signal on the pilot channel, the n bits indicating which paging channels are active.

10. The method of claim 9, wherein the n bits of the processing step are located in a predetermined locations within a slot of data.

11. The method of claim 8, wherein the powering up step includes substeps of acquiring a synchronization channel of the radio communication system so as to synchronize timing of the communication device to the radio communication system, and acquiring and reading those paging channels indicating activity.

12. The method of claim 8, wherein the powering up step includes a substeps of powering down the analog receiver circuitry, the digital receiver circuitry and the digital signal processor after those paging channels indicating activity in the detecting step have been monitored by the communication device and any incoming calls received by the radio communication device have been completed, and continuing at the providing step.

13. A apparatus for reducing power consumption in a communication device, the apparatus comprising:

analog receiver circuitry to receive signals from a communication system;

digital receiver circuitry including searcher circuitry in a portion thereof, the digital receiver circuitry to provide a baseband demodulated data stream from the incoming signals coupled from the analog receiver circuitry, the searcher circuitry to detect a common pilot channel signal in the data stream;

a digital signal processor including call processor circuitry in a portion thereof, the digital signal processor to decode messages in the data stream, the call processor to retrieve predetermined bits indicating activity on paging channels of the radio communication system;

the analog receiver circuitry, the searcher circuitry, and the call processor circuitry to be powered on from an initial sleep mode such that call processor can retrieve predetermined bits indicate activity on paging channels of the radio communication system; and

where no activity is indicated by the predetermined bits, the analog receiver circuitry, the searcher circuitry, and the call processor circuitry to be powered down so as to reduce power consumption, and

where activity is indicated by the predetermined bits, the digital receiver circuitry and the digital signal processor to be powered up such that those paging channels indicating activity are monitored by the communication device.

14. The apparatus of claim 13, wherein the predetermined bits include at least four bits punctuating a Walsh code of 0 comprising the pilot channel signal, the at least four bits indicating which of the paging channels are active.

15. The apparatus of claim 14, wherein the at least four bits are located at predetermined locations within a slot of data, the at least four bits indicating which of the paging channels are active.

16. The apparatus of claim 13, wherein activity indicated by the predetermined bits directs the digital receiver circuitry and the digital signal processor to acquire a synchronization channel of the radio communication system so as to synchronize timing of the communication device to the radio communication system and to acquire and read those paging channels indicating activity.

17. The apparatus of claim 13, wherein the analog receiver circuitry, the digital receiver circuitry and the digital signal processor are powered down after those paging channels indicating activity have been monitored by the communication device and any incoming calls received by the radio communication device have been completed.

18. A radio communication system for reducing power consumption in a radiotelephone, comprising:

a base station, said base station configured to transmit a pilot channel signal punctuated by predetermined bits indicating paging activity on particular paging channels; and

at least one radiotelephone having analog and digital receiver circuitry to receive signals from the radio communication system and provide a baseband demodulated data stream, the digital receiver circuitry including searcher circuitry to detect a common pilot channel signal in the data stream and a digital signal processor including call processor circuitry in a portion thereof, the digital signal processor to decode messages in the data stream, the call processor to retrieve predetermined bits of the pilot channel indicating activity on paging channels of the radio communication system, the radiotelephone configured to periodically power up the analog receiver circuitry, the searcher circuitry, and the call processor circuitry from an initial sleep mode such that the call processor can read the predetermined bits of the pilot channel signal indicating activity on paging channel of the radio communication system such that;

where no paging activity is indicated by the predetermined bits of the pilot channel signal, the radiotelephone powers down the analog receiver circuitry, the searcher circuitry, and the call processor circuitry, and

where paging activity is indicated by the predetermined bits of the pilot channel signal, the radiotelephone powers up the digital receiver circuitry and digital signal processor circuitry to read those particular paging channels.

19. The radio communication system of claim 18, wherein the base station is part of at least one of a personal digital cellular (PDC) system, a Japan digital cellular (JDC) system, a code division multiple access (CDMA) system, a direct sequence code division multiple access (DS-CDMA) system, a groupe speciale mobile (GSM) system, and a slotted paging mode groupe speciale mobile (GSM-DRX) system.