Protocol for packet data communication system

Details Protocol for packet data communication system Protocol for packet data communication system

H - Electricity

04

L

H04L 29/06 (2006.01) H04L 12/28 (2006.01) H04L 12/56 (2006.01) H04Q 7/22 (2006.01)

Patent

CA 2119334

A packet data transmission system is used to link a number of remote hand-held data-gathering units such as bar code readers to a central computer. Data packets are sent from the remote units by a spread spectrum RF link to intermediate base stations, then sent by the base stations to the central computer by a serial link. The remote hand-held units initiate an RF exchange to and from the bass stations, receiving only during a time window following a transmission from the remote unit. The base stations cannot initiate an exchange with the remote units, but instead send data to the remote units only as part of the exchange. To alert a remote unit when a message is waiting at a base station to be sent to a particular unit, some of the acknowledge (base-to-remote) packets sent by the base station may contain an identification such as a list of all remote units (identified by ID number) which have messages waiting. Alternatively, a bit map can be used to identify these remotes. These base-to-remote packets with the identification of remotes with messages waiting are called "announcements." Each remote unit (if not engaged in regular exchanges for a time interval) periodically listens (activates its receiver) to receive an announcement packet containing such a list or bit map and decodes this announcement to see if it has a message waiting. If so, this remote unit then sends a transmit packet so the base can send the waiting message in an acknowledge packet.

Affiliated with

Also associated with

Rating

Protocol for packet data communication system does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Protocol for packet data communication system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Protocol for packet data communication system will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1389444