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:
Apr. 18, 2000
Filed:
Jul. 07, 1997
Michel Claude Lambourg, Chaville, FR;
Matra Communication, , FR;
Abstract
The equipment comprises a radio terminal adapted to calls with a public mobile telephony network supporting voice transmission channels and data channels, and an extension unit which can be connected to a data interface of the terminal and allowing calls on the data channels of the network. This extension unit comprises a microphone, an earphone, a vocoder and a ciphering module. It has the same external appearance as a conventional mobile radio terminal. In a security call mode, the signal coming from the microphone of the extension unit is processed by the vocoder and then by the ciphering module in order to produce data sent to the data interface of the terminal, and the data received from the data interface of the terminal are processed by the ciphering module and by the vocoder in order to control the earphone of the extension unit.