The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 28, 1994
Filed:
Feb. 04, 1993
Kevin Gardeck, Algonquin, IL (US);
Kevin M Cutts, Schaumburg, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
Within a communication system, an encryption controller receives unit identification information from a plurality of encrypting/decrypting communication units. For any individual communication unit, the encryption controller uses the unit identification associated with that transmitting communication unit to determine if it contains updated encryption key information. If the transmitting communication unit is not currently updated, a group call is used to send the current encryption key information to all communication units within the transmitting communication unit's group, thereby updating all active, non-current communication units. After a first predetermined period of time has elapsed, this process is allowed to repeat.