Terry,
Is it possible to get a copy of the whole ITU Part 5B report?
--
73 Warren K2ORS
WD2XGJ
WD2XSH/23
WE2XEB/2
WE2XGR/1
On Fri, Nov 5, 2010 at 1:41 PM, Terry GW0EZY <[email protected]> wrote:
> I guess these tests relate to a proposed new system being discussed in ITU
> Working Party 5B:
>
> PROPOSED MODIFICATIONS TO PRELIMINARY DRAFT NEW
> REPORT ITU-R M.[500 kHz]
> Utilization of the 495-505 kHz band by the maritime mobile
> service for the digital broadcasting (from shore-to-ships)
> of information related to safety and security
>
> The draft new report has contributions from France and USA. Some extracts
> from the documents:
>
> This preliminary draft Report provides information on a digital broadcasting
> system working in the 500 kHz band. This system is intended to be used to
> broadcast from shore to ships information related to navigational and
> meteorological warnings, urgent information and other information related to
> safety and security. The system will utilize the band 495-505 kHz and have
> the same coverage area as the current NAVTEX system operating at 490 kHz and
> 518 kHz. New digital technology provides a greatly improved data throughput
> from that provided by the current NAVTEX system. It also provides protection
> to the incumbent NAVTEX system.
>
> This system will operate in a manner similar to the current NAVTEX system.
> The coast stations will be spaced along the coast approximately [500]
> nautical miles apart. All the transmitters on a coast will share the 10 kHz
> channel by transmitting in a specific time slot. An example of time slot
> allocations for a network of 500 kHz broadcast transmitters for the Atlantic
> coast of Europe is based on 3-minute slots of a 60 minute cycle. There is
> also discussion on using 495-500 kHz and 500 - 505 kHz as two slots for a
> "permanent mode"
>
> The radiated power from the regional coast station transmitter should be
> what is sufficient to cover the intended service area of that coast station.
> The power would be decreased at night during periods of better r.f.
> propagation. The estimated coverage area from shore is approximately 320
> nautical miles with a radiated power of 1 kW and 400 nautical miles with a
> radiated power of 5 kW. The modulation is of type OFDM with N-QAM. An
> example of 64-QAM @ 47.4 kbps.system has a data rate of 100 bit/second with
> a 300 Hz channel. This system would have a data rate of up to 47 400
> bits/second with a 10 kHz channel.
>
> A transmitter site in France is mentioned in the report: Pointe de Corsen
> coordinates: 48.414444 N, 4.794444 W. Google Earth shows some sort of
> installation there.
>
> 73 Terry GW0EZY
>
>
>
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