Chris J Calvert

US Patent:

20110075704, Mar 31, 2011

Filed:

Dec 11, 2009

Appl. No.:

12/636128

Inventors:

John Bettendorff - San Francisco CA, US
Chris Calvert - Roswell GA, US

Assignee:

Cellnet Innovations, Inc. - Alpharetta GA

International Classification:

H04B 1/713

US Classification:

375133, 375139, 375E01033

Abstract:

Methods and systems for sending a broadcast message in frequency hopping and other systems. Instead of sending a complete message separately to each device, a relatively small packet or “chirp” is sent. These chirps are either targeted at known devices or sent in a manner to sweep the RF band. Devices that hear the chirps get information about the channel and/or time that the broadcast data will be sent. These devices then listen for the broadcast data as instructed, e.g., at the specified time on the specified channel. A system may alternatively, or in addition, use a scheduled hopping sequence break as a broadcast moment. Such a broadcast moment can be scheduled to periodically interrupt the node hopping sequences so that, at such times, many or all nodes are scheduled to be on the same channel for potential broadcasts.