05627517 is referenced by 209 patents and cites 12 patents.

In a freight tracking and routing system, each individual package is provided with a tag physically attached thereto. The tag includes a radio or infrared transceiver, and a microprocessor. At important nodes at geographical locations within the distribution system, location transceivers broadcast signals representative of their locations. The microprocessor, in response to receiving a desired destination signal, emits a signal commanding external equipment to take the package so that it remains at the desired location. The tags are also capable of being electronically queried, or alternately can emit distress signals when they do not reach a particular location at a particular time.

Title
Decentralized tracking and routing system wherein packages are associated with active tags
Application Number
8/548360
Publication Number
5627517
Application Date
November 1, 1995
Publication Date
May 6, 1997
Inventor
Roy Want
Mountain View
CA, US
Marvin M Theimer
Mountain View
CA, US
Agent
R Hutter
Assignee
Xerox Corporation
CT, US
IPC
G08B 13/14
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