System and method for low power radio operation in a wireless packet network

• US 7,515,556 B2
• Filed: 04/25/2006
• Issued: 04/07/2009
• Est. Priority Date: 04/25/2006
• Status: Expired due to Fees

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Arch Rock Corp. (Cisco Systems, Inc.)
• Inventors: Culler, David E, Hui, Jonathan W
• Primary Examiner(s): Nguyen; Duc
• Assistant Examiner(s): Addy; Anthony S
• Application Number:
  US11/411,404
• Publication Number:
  US 20070248071A1
• Time in Patent Office: 1,078 Days
• Field of Search: 370/241, 370/311, 370/328, 370/329, 713/320, 713/321, 713/323, 713/324, 4553431-3435, 455/522, 455/573, 455/574
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0261 managing power supply demand, e.g. depending on battery level
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A system and method allows devices to send and receive packets while using power to do so to the extent needed, thereby conserving power.

Claims

1. A system for receiving at least one data packet, the system comprising:

a sleep manager having an output coupled to an input of a radio, the sleep manager for;

providing at the sleep manager output a first signal for causing the radio to draw power, for a first amount of time, at a first level below a level which is used to receive at least one data packet; and

providing a second at the sleep manager output substantially at the end of the first amount of time; and

wherein the radio attempts to receive and provide at an output a set of data, at least in part responsive to the second signal at the sleep manager second output; and

the system additionally comprising

a chirp packet delimiter manager having an input coupled to the radio output for receiving the set of data, the chirp packet delimiter manager for determining whether the set of data corresponds to a first packet type, and responsive to the set of data corresponding to the first packet type, identifying a second amount of time, responsive to the set of data, and for providing the second amount of time at a chirp packet delimiter manager output coupled to a sleep manager input; and

wherein the sleep manager is additionally for, responsive to the second amount of time received at the sleep manager input, providing at the sleep manager output a third signal for causing the radio to draw power, for a duration responsive to the second amount of time received at the sleep manager input, at the first level below that which is used to receive at least one data packet, and at the end of the duration, providing at the sleep manager output a fourth signal for causing the radio to receive the at least one data packet.

2. The system of claim 1, additionally comprising an energy identification manager having an input/output coupled to the radio output and an output coupled to the radio input, and an input coupled to the sleep manager output for receiving the second signal, the energy identification manager for:

responsive to the second signal, providing a signal via the energy identification manager output, for causing the radio draw power at a second level, higher than the first level, and to determine a level corresponding to energy being received by the radio on at least one frequency and to provide an indication of the level corresponding to the energy at the radio output;

receiving via the energy identification manager output the indication of the level from the radio;

determining whether the level exceeds a threshold and;

responsive to the level exceeding the threshold, providing the second signal, via the energy identification manager output, for causing the radio to receive and provide at the radio output the set of data.

3. The system of claim 2, additionally comprising:

a packet receiver having an input coupled to the radio output for receiving the at least one data packet, and for providing a signal at an output responsive to receipt of said at least one data packet; and

a piggyback manager having an input coupled to the packet receiver output for receiving the signal, the piggyback manager for, responsive to the signal received at the piggyback manager input, causing the radio to at least attempt to broadcast an additional at least one data packet substantially immediately after the at least one data packet is received by the radio.

4. The system of claim 2, wherein the chirp packet delimiter manager determines whether the set of data corresponds to a first packet type by checking the set of data for a pattern.

5. The system of claim 2 wherein a description of the second amount of time is contained in the set of data.

6. The system of claim 2, wherein:

the energy identification manager additionally comprises an output coupled to the sleep manager input;

the energy identification manager provides an alternate signal at an energy identification manager output responsive to the level not exceeding the threshold; and

the sleep manager is additionally for;

responsive to the alternate signal, providing at the sleep manager output a fifth signal for causing the radio to draw power, for a third amount of time, substantially equal to the first amount of time, at the first level; and

providing a sixth signal at a sleep manager second output substantially at the end of the third amount of time;

and wherein the radio additionally attempts to receive and provide at the radio output an additional set of data at least in part responsive to the sixth signal.