Re: BBC to help DMB in the battle against DVB-H



Pierre PANTALÉON wrote:
DAB sounds worse than FM a écrit :

2K GI 1/32 is the same as the UK uses, and the GI duration is only
7us. The approximation for SFNs is that you can use a separation
between transmitters equal to the distance the signal travels in the
GI, which is: 3 x 10^8 x 7 x 10^-6 = 2.1 km!!!!!

So, unless your transmitters are separated by only 2 km the SFN
should not work.

Ok i understand why it don't run well ! ;)

But They want have an high bitrate per mux (24 Mbps), so ...

What configuration would have to use to have a bitrate of 24 Mbps and
true SFN with 45 km between transmitters ?


You've got to use 8K and GI 1/8 or 1/4.


Use a new system which can be very efficient, and don't run, it
enervate me. And at the frontier, if every countries do same thing,
UHF aren't sufficient :(


I don't understand.

If we replace technology by another which use plenty of UHF channel,
it's not interessant.
The number of program is reduced, and planning is difficult to do.

at east of France, there Belgium, Luxembourg, Germany, switzerland.
If each country use bad UHFchannel, it become very difficult to find
free channel to broadcast TV mux or others.

In fact, it stop competition for new mux and new channels or new
technology like DVB-H for example.


You should move to an island. ;-)


--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info

Find the cheapest Freeview & DAB prices:
http://www.digitalradiotech.co.uk/freeview/freeview_receivers.php
http://www.digitalradiotech.co.uk/dab/dab_radios.php


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