Power management system for a mobile station

• US 6,680,920 B1
• Filed: 02/08/2000
• Issued: 01/20/2004
• Est. Priority Date: 10/29/1997
• Status: Expired due to Term

• Current Assignee: Commx Wireless LLC (Novelision Holding LLC)
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Wan, Yongbing
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Tsegaye, Saba
• Application Number:
  US09/499,911
• Time in Patent Office: 1,442 Days
• Field of Search: 370/311, 370/328, 370/329, 370/337, 370/341, 370/347, 455/434, 455/38.3, 455/422, 455/38.2, 455/343, 455/515, 455/412, 455/418, 455/419, 455/420, 455/574, 455/458
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0293 having a sub-controller with a low clock frequency switching on and off a main controller with a high clock frequency
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A power management system for a mobile station reduces standby mode processing by receiving and processing single time slots of a short paging channel. Each single time slot of a short paging channel includes a mobile station identifier which alerts a receiving mobile station that a pending telephone call or paging message may be directed to the mobile station. Once so alerted, the mobile station receives and processes full paging channels comprising four time slots to determine whether the mobile station is the intended recipient of the telephone call or paging message. If the mobile station determines that it is not the intended recipient, then the mobile station resumes receiving and processing single time slots of the short page channel. Processing fewer time slots of data for purposes of call detection conserves mobile station battery power.

Claims

1. A method of operating a mobile station having a software instruction processing unit and a software instruction storage comprising a computer-readable medium, comprising:

scanning broadcast information in a wireless communication network for a short page channel;

receiving a single time slot of said short page channel containing one group of call alert data, said wireless communication network operating in accordance with the GSM standard, said single time slot being less than one millisecond in duration and representing less than 128 data bits; and

processing said one group of call alert data and determining from said group of call alert data whether a pending telephone call or paging message may have been directed to the mobile station.

2. The method of claim 1, further comprising:

entering an idle state during a time period between broadcasts of said short page channel, in said idle state the mobile station does not scan for a short page channel or receive or process call alert information;

consuming power at a first rate during said scanning for said short page channel and during receiving or processing said call alert information; and

consuming power at a second rate in said idle state, said second rate being less than said first rate.

3. The method of claim 2, further comprising:

providing a master clock and a low precision clock, said low precision clock less precise than said master clock;

timing the receipt of a single short page channel time slot using said low precision clock, said low precision clock consuming less power during a time interval than said master clock;

timing said idle state using said low precision clock; and

shutting down said master clock during said idle state.

4. A method of operating a mobile station, comprising:

receiving a short page channel transmitted by a wireless communication system operating in accordance with the GSM standard;

extracting paging data from a time slot of said short page channel;

determining from said paging data in said time slot that a telephone call or paging message may have been directed to said mobile station, said time slot being less than one millisecond in duration and representing less than 128 bits; and

receiving four time slots of a paging channel and responsively determining whether the mobile station is an intended recipient of a telephone call or paging message.

5. The method of claim 4, further comprising establishing a communication link to a communication device responsible for initiating said telephone call or paging message.

6. The method of claim 5, further comprising comparing a mobile station identity value to a short page identity value to make said determination that said telephone call or paging message may have been directed to said mobile station.

7. A method of reducing requirements for processing broadcast control data in a mobile station, comprising:

receiving a bit of a time slot of a TDMA frame;

storing said bit in a data storage area, said bit being reserved for updating broadcast control information;

comparing said bit to a prior received bit stored in said data storage area and, if said compared bits differ, directing the mobile station to receive and process a next transmitted broadcast control channel to update communication parameters of the mobile station; and

storing the newly received bit in place of the prior received bit.

8. A method of operating a wireless communication system, comprising:

generating in a mobile switching center a first single time slot of a short page channel, said first single time slot including a first mobile station identifier value;

transmitting said first single time slot from said mobile switching center to a base station;

generating in said mobile switching center a paging channel having four time slots, said four time slots including a second mobile station identifier;

transmitting said four time slots from said mobile switching center to said base station;

receiving in a base station said first single time slot and said four time slots;

transmitting said first single time slot in a short page channel and said four time slots in a paging channel from said base station to a cell;

receiving in said cell with a mobile station identified by said first mobile station identifier and said second mobile station identifier, said first single time slot from said short page channel;

extracting said first mobile station identifier from said first single time slot to determine that a pending telephone call or paging message may be directed to said mobile station;

receiving with said mobile station, upon said determination, said four time slots from said paging channel;

extracting said second mobile station identifier to conclude that said mobile station is the intended recipient of said telephone call or paging message; and

initiating in said mobile station, upon said conclusion, call establishment procedures to create a communication link between said mobile station and a communication device responsible for initiating said telephone call or paging message.

9. The method of claim 8, further comprising:

including in said first single time slot a broadcast control update bit having a first value if the content of a most recently transmitted broadcast control channel in said cell did not change from the content of an immediately preceding broadcast control channel transmitted in said cell, said bit having a second value if the content of the said recently transmitted broadcast control channel is different from the content of said immediately preceding broadcast control channel; and

extracting with said mobile station said update bit from said first single time slot and, if said update bit has said second value, then said mobile station receiving and processing a next transmitted broadcast control channel.

10. The method of claim 8, further comprising:

storing a paging group value in a data storage area, said paging group value specifying first paging channels and being assigned to said mobile station by a mobile switching center; and

storing a paging channel skipping value in said data storage area, said paging channel skipping value specifying a subset of said first paging channels, said subset identifying paging channels transmitted less frequently than said first paging channels, said mobile station receiving and processing said subset of said first paging channels.

11. The method of claim 10, further comprising:

timing said receipt of said four time slots by said mobile station using a master clock;

transmitting a second single time slot to said base station;

transmitting from said base station to said cell said second single time slot in said short page channel, said mobile station receiving said second single time slot from said short page channel upon determining from said receipt of said first single time slot that a pending telephone call or paging message is not directed to said mobile station;

timing with a low precision clock the duration of an idle state wherein said mobile station does not receive, transmit, or process data, said duration of said idle state occurring after said receipt by said mobile station of said first single time slot and before said receipt by said mobile station of said second single time slot, said second single time slot containing sufficient synchronization bits to permit said receipt of said second single time slot; and

shutting said master clock down during said idle state, said low precision clock consuming less power during a time interval than said master clock.