User Manual

GE863-PRO

Product Description

80285ST10036a Rev. 1 DRAFT- 24/04/08

3.31.3 Jammed Detect & Report Extension

3.31.3.1 Overview

The Jammed Detect & Report feature allows a Telit GE863-PRO

module to detect the presence of a

disturbing device such as a Communication Jammer and give indication to the user and/or send a

report of that to the network.

This feature can be very important in alarm, security and safety applications that rely on the module

for the communications. In these applications, the presence of a Jammer device can compromise the

whole system reliability and functionality and therefore shall be recognized and reported either to the

local system for countermeasure actions or to the network providing remote actions.

An example scenario could be an intrusion detection system that uses the module for sending the

alarm indication for example with an SMS to the system owner, and thief incomes using a Jammer to

prevent any communication between the GSM module and the network.

In such a case, the module detects the Jammer presence even before the break in and can trigger an

alarm siren, other communication devices (PSTN modem) or directly report this condition to the

network that can provide further security services for example sending SMS to the owner or police.

Obviously this last service depends also from network infrastructure support and it may not be

supported by some networks.

3.31.4 CMUX

CMUX ( Converter-Multiplexer) is a multiplexing protocol implemented in the Telit module that can be

used to send any data, SMS, fax, TCP data.

3.31.4.1 Product architecture

The Multiplexer mode enables one serial interface to transmit data to four different customer

applications. This is achieved by providing four virtual channels using a Multiplexer (Mux).

This is especially advantageous when a fax/data/GPRS call is ongoing. Using the Multiplexer features,

e.g. controlling the module or using the SMS service can be done via the additional channels without

disturbing the data flow; access to the second UART is not necessary.

Furthermore, several accesses to the module can be created with the Multiplexer. This is of great

advantage when several independent electronic devices or interfaces are used.