DEVICE AND METHOD FOR DETECTING THE PRESENCE OF AN OPERATING CELLULAR TELEPHONE OF THE GSM TYPE OR ANY OTHER MOBILE UNIT

摘要

The invention concerns an equipment for detecting a cellular telephone in a protected zone characterised in that it comprises at least a HF receiver circuit whereof the output is connected to a microcomputer controlled so as to detect at least a service code representing the operation of a cellular telephone system and for transmitting a warning signal in the event such a service code is detected.