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. 22, 1993
Filed:
Apr. 03, 1991
Steven T Barrett, Plantation, FL (US);
Kevin M Laird, Haltom City, TX (US);
Richard E Murray, Coral Springs, FL (US);
James M O'Connor, N. Richland Hills, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A radio (100) transmits and receives encrypted signals having unencrypted key identifiers, allowing other radios having the corresponding key identifiers and encryption keys to communicate with radio (100). Prior to transmitting an encrypted message, radio (100) selects a unique key identifier automatically and uses the corresponding encryption key to encrypt the message that will be transmitted. Radio (100) transmits the key identifier in an unencrypted format with the encrypted message in order to allow other radios to determine the encryption key used in encrypting the message. When receiving an encrypted message, radio (100) uses the predetermined process stored in the radio (100) to properly select the proper encryption key for use in decrypting the incoming message.