Method and apparatus for reducing power consumption of slotted mode mobile communication terminal

• US 7,142,896 B2
• Filed: 01/17/2003
• Issued: 11/28/2006
• Est. Priority Date: 01/17/2002
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Ju-Bong
• Primary Examiner(s): TIEU, BINH KIEN
• Application Number:
  US10/347,012
• Publication Number:
  US 20030148800A1
• Time in Patent Office: 1,411 Days
• Field of Search: 455/574, 455/343.1, 455/343.2, 455/343.4, 340/7.32, 340/7.33, 340/7.36, 370/311, 370/320, 370/335, 370/342, 370/515
• 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 52/0235 where the received signal is a power saving command
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus for reducing power consumption of a mobile communication terminal operated at a slotted mode in a spread spectrum communication system such as a CDMA cellular mobile communication system. The mobile communication terminal reduces a paging channel monitoring time by entering a sleep mode or a wake-up mode at an arbitrary timing instead of a PN code rollover period, resulting in the increment of a standby time of the terminal.

Claims

1. A method for increasing a sleep period of a communication circuitry in a mobile communication terminal, the communication circuitry being repeatedly and periodically woken up for monitoring a paging channel received from a mobile communication system in an allocated paging channel slot period that is periodically repeated, the communication circuitry sleeping in a non-allocated paging channel slot period, the method comprising the steps of:

a) setting up hardware parameters for powering off the communication circuitry when a sleep mode determination command is generated in the allocated paging channel slot period;

b) when the hardware parameters setup is completed, immediately entering a sleep mode to power off the communication circuitry; and

c) waking the mobile communication terminal at a preset time period after the next allocated paging channel slot period, said preset time period based on at least one of a coding method, a frame length and searcher parameters.

2. The method as set forth in claim 1, wherein step c) comprises:

calculating a first time period from the sleep mode determination command to an initiation timing of the next allocated paging channel slot period in units of a PN (Pseudo-random Noise) code rollover period, and determining the first time period as a reference sleep time period;

measuring a second time period to a powering-off timing of the communication circuitry since a sleep mode indication command to the communication circuitry is generated in response to the sleep mode determination command, and storing the second time period as a sleep time offset;

determining a wake-up time offset considering a time period needed for the mobile communication terminal to establish a synchronization re-acquisition with the mobile communication system;

after entering the sleep mode, summing up the reference sleep time period, the sleep time offset and the wake-up time offset, and driving a sleep mode timer having a duty cycle of a value where a predetermined maximum time delay value is subtracted from the summed result; and

when the sleep mode timer is expired, powering on the communication circuitry by entering a wake-up mode.

3. The method as set forth in claim 2, further comprising:

after powering on the communication circuitry, calculating and setting a PN state corresponding to the wake-up time offset.

4. An apparatus for reducing power consumption in a mobile communication terminal, comprising:

a communication circuitry that is repeatedly and periodically woken up for monitoring a paging channel received from a mobile communication system in an allocated paging channel slot period that is periodically repeated, and sleeps in a non-allocated paging channel slot period; and

a control unit that sets up hardware parameters for powering off the communication circuitry when a sleep mode determination command is generated in the allocated paging channel slot period, enters a sleep mode to power off the communication circuitry immediately upon completing the hardware parameters set-up, and wakes the mobile communication terminal at a preset time period after the next allocated paging channel slot period, said preset time period based on at least one of a coding method, a frame length and searcher parameters.