Battery efficient operation of scheduled access protocol

• US 5,241,542 A
• Filed: 08/23/1991
• Issued: 08/31/1993
• Est. Priority Date: 08/23/1991
• Status: Expired due to Term

• Current Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Huang, Chia-Chi, Natarajan, Kadathur S.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Kizou, Hassan
• Application Number:
  US07/749,234
• Time in Patent Office: 739 Days
• Field of Search: 370/95.1, 370/95.3, 370/104.1, 370/29, 370/85.2, 370/85.7, 370/94.1, 455/53.1, 455/54.1, 455/343, 455/38.3, 340/825.44, 340/311.1, 379/58
• US Class Current: 370/311
• CPC Class Codes: G06F 1/3215 Monitoring of peripheral devices
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus for conserving battery power in a wireless link adapter of a battery operated computer such as a portable laptop computer, as controlled by a scheduled multiaccess protocol. The portable computer is operable as a mobile unit in a multi-cell wireless network. The scheduled access multiaccess protocol is implemented to effectively conserve battery power by suitable control of the state of the controller, the transmitter and receiver units at the wireless link adapter by scheduling when the adapter is in a normal running mode, or a standby mode in which power is conserved.

Claims

1. A method of conserving battery power in a wireless link adapter of battery powered computers operable in a multiaccess protocol for wireless communication between n, where n is an integer, of said battery powered computers and a base station, with said protocol including a designation of which ones of said n computers are to communicate with said base station, said method comprising the steps of:

partitioning said multiaccess protocol into at least one frame including a header AH having n bits, with each of said n bits being assigned to a corresponding one of said n battery powered computers, with a given one of said n computers being scheduled for communication with said base station during said frame when its corresponding one of said n bits is in a first state, and for not being in communication when in a second state, with the remainder of said frame being divided into a plurality of slots in a time duration TA, with there being at least one slot dynamically assigned to only the ones of said n battery powered computers scheduled to communicate with said base station;

turning ON said battery power of said wireless link adapter for each of said n battery powered computers for the duration of header AH;

turning OFF battery power for said time duration TA for each wireless link adapter of the n battery powered computers that is not scheduled to communicate with said base station; and

turning ON battery power only during the at least one slot time of TA scheduled, for each wireless link adapter of the n battery powered computers scheduled to communicate with said base station, and turning OFF battery power for the remaining slots of TA.

2. The method claimed in claim 1, wherein the communication scheduled is for said base station to transmit to the scheduled ones of said battery powered computers during the time duration TA.

3. The method of claim 2, including the steps of:

including a second frame in said multiaccess protocol, including a header BH having n bits, with each of said n bits being assigned to a corresponding one of said n battery powered computers, with a given one of said n computers being scheduled for transmitting information to said base station during said second frame when its corresponding one of said n bits is in a first state, and for not transmitting information when in a second state, with the remainder of said second frame being divided into a plurality of slots in a time duration TB, with there being at least one slot dynamically assigned to only the ones of said n battery powered computers scheduled to transmit to said base station;

turning on said battery power of said wireless link adapter for each of said n battery powered computers for the duration of the header BH;

turning OFF battery power for said time duration TB for each wireless link adapter of the n battery powered computers that is not scheduled to transmit to said base station; and

turning ON battery power only during the at least one slot time of TB scheduled for each wireless link adapter of the n battery powered computers scheduled to transmit to said base station, and turning OFF battery power for the remaining slots of TB.

4. The method of claim 3, including the steps of:

including a third frame in said multiaccess protocol, with said third frame including a header CH which includes a designation of the number of slots available in the remainder of said third frame in time duration TC, with said third frame being allotted to contention mode transmission from said n battery powered computers to said base station;

turning ON said battery power of said wireless link adapter of each of said n battery powered computers for the duration of the header CH;

turning OFF said battery power of the receiver of each wireless link adapter of each of said n battery power computers for the time duration TC;

turning OFF the battery power of the transmitter in said wireless link adapter of any of said battery powered computers that do not wish to transmit to said base station during said third frame; and

turning ON said battery power for a transmitter of said wireless link adapter in a given battery powered computer for at least one slot in said third frame for transmitting from said given battery powered computer to said base station, with said battery power for said transmitter of said wireless adapter link being turned OFF for the remaining time slots of said third frame.

5. A method of conserving battery power in a wireless link adapter of battery powered computers operable in a multiaccess protocol for wireless communication between n, where n is an integer, of said battery powered computers and a base station, with said protocol including a designation of which ones of said computer are to communicate with said base station, said method comprising the steps of:

partitioning said multiaccess protocol into at least one frame including a header AH having n bits, with each of said n bits being assigned to a corresponding one of said n battery powered computers, with a given one of said n battery powered computers being scheduled for communication with said base station during said at least one frame, when its corresponding one of said n bits is in a first state, and for not being in communication when in a second state, with the remainder of said at least one frame being divided into a plurality of slots in a time duration TA, with there being at least one slot dynamically assigned to only the ones of said n computers scheduled to communicate with said base station;

running said wireless link adapter of each of said n battery powered computers in a normal running mode for the duration of header AH;

running in an idle mode for said time duration TA, said wireless link adapter of each of the n battery powered computers that is not scheduled to communicate with said base station; and

running said wireless link adapter in a normal mode only during the at least one slot time of TA scheduled for each of the n battery powered computers that is scheduled to communicate with said base station, and running it in an idle mode for the remaining slots of TA.

6. A method of conserving battery power in a wireless link adapter of battery powered computers operable in a multiaccess protocol for wireless communication between n, where n is an integer, of said battery powered computers and a base station, with said protocol including a designation of which ones of said n computers are to communicate with said base station, said method comprising the steps of:

partitioning said multiaccess protocol into at least first and second frames;

including in said first frame a header AH having n bits, with each of said n bits being assigned to a corresponding one of said n battery powered computers, with a given one of said n computers being scheduled for receiving information from said base station during said first frame when its corresponding one of said n bits is in a first state, and for not receiving information when in a second state, with the remainder of said frame being divided into a plurality of slots in a time duration TA, with there being at least one slot dynamically assigned to only the ones of said n battery powered computers scheduled to receive information from said base station;

running said wireless link adapter for each of said n battery powered computers in a normal running mode for the duration of header AH;

running said wireless link adapter in an idle mode for said time duration TA for each of the n battery powered computers that is not scheduled to receive information from said base station;

running said wireless link adapter in a normal running mode only during the at least one slot time of TA scheduled for each of the n battery powered computers scheduled to receive information from said base station;

including in said second frame a header BH having n bits, with each of said n bits being assigned to a corresponding one of said n battery powered computers, with a given one of said n computers being scheduled for transmitting information to said base station during said second frame when its corresponding one of said n bits is in a first state, and for not transmitting information when in a second state, with the remainder of said second frame being divided into a plurality of slots in a time duration TB, with there being at least one slot dynamically assigned to only the ones of said n battery powered computers scheduled to transmit to said base station;

running said wireless link adapter for each of said n battery powered computers in a normal running mode for the duration of the header BH;

running said wireless link adapter in an idle mode for said time duration TB for each of the n battery powered computers that is not scheduled to transmit to said base station; and

running said wireless link adapter in a normal running mode only during the at least one slot time of TB scheduled for each of the n battery powered computers scheduled to transmit to said base station, and running it in an idle mode for the remaining slots of TB.

7. The method of claim 6, including the step of:

including a third frame in said multiaccess protocol, with said third frame including a header CH which includes a designation of the number of slots available in the remainder of said third frame in a time duration TC, with said third frame being allotted to contention mode transmission from said n battery powered computers to said base station;

running in the normal running mode the receiver in the wireless link adapter of each of said n battery powered computers for the duration of the header HC;

running in the idle mode the transmitter in said wireless link adapter of any of said n battery powered computers that do not wish to transmit to said base station during said third frame; and

running the transmitter in said wireless link adapter in a given one of said n battery powered computers in a normal running mode at least during one slot in said third frame for transmitting communications from said given one of said n battery powered computer to said base station, with said transmitter in said wireless link adapter running in an idle mode for the remaining time slots of said third frame.