RADIO SYSTEM IN CONFINED ENVIRONMENT BETWEEN MOBILE
TELEPHONE SYSTEM TERMINALS
Keywords: RADIO SYSTEM - TUNNEL - SHF - WAVEGUIDE EFFECT
- TRANSPONDER
General Description
This patented technology concerns a radio system in closed environment.
Considering the so called "waveguide" effect, it is known that the super
high frequency (SHF) radioelectric wave propagates generally well in
confined places in particular road or railway tunnels.
Emergency and Security services (for example fire brigades) use cellular
phone working in 80 / 160 MHz bands.
In a confined space, the transmitting range of those devices remains
low at these frequencies.
An individual portable module is connected to a mobile phone system
terminal and comprises a microwave frequency transponder for receiving
a HF signal transmitted by the terminal and re-transmitting a SHF signal
in the confined environment.
The main innovative aspect is that the use of radiocommunication
materials running in 80 MHz and 160 MHz, usually make the radio contact
ineffective in tunnels longer than 200 meters (because of very bad propagation
of radio electric waves in confined space for frequencies below 400
MHz)
Attempts made in a long length tunnel showed that it was possible to
establish SHF connections of several kilometers (4 km) with a low broadcast
power (3 w).
Many kinds of applications can be considered
- All kinds of security and emergency services having confined areas
in their sector of intervention shall be interested.
Indeed this invention can be used not only in tunnels but also in underground
garage.
This patent has already been prototyped and tested by fire brigades,
by intervention forces in the subway of Lyon and also in the subterranean
rainwater network.
- Particularly developed to the use in tunnels (following to the Mont.
Blanc tunnel catastrophe), it's a necessity when radiant cables equipping
some tunnels and allowing to communicate with the outside, are destroyed.
Type of collaboration sought:
Licence agreement
Intellectual Property Rights:
Patent granted
Type of partner:
industrial
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