Craig Birkmaier wrote: > The problem is not related to the transmission infrastructure. I'm glad that at least you acknowledge this. Although in that FCC report, it stated clearly that these nationwide SFNs were an intrinsic advantage of COFDM. They are not. They are a bear for any system to implement properly, but in principle (at least) any system can. > Perhaps this is why you cannot get it through your thick head > that the infrastructure I am advocating is not only possible, > but desirable, as it would provide much higher spectral > efficiency. Or perhaps it's because when you arm wave, you think you are describing details. What you claim to describe clearly is internally inconsistent. > In densely populated areas where markets are closely spaced, > the infrastructure would rely on a few sticks at relatively low > HAAT and power, with a larger number of on-channel gap fillers. And yes, what you describe is what doesn't work. If you want to cover an entire market area of typical US market size, without creating large pockets with no reception, these low power and low HAAT sticks will interfere terribly among each other. Especially so if they are passive repeaters. Take a market area of, say, 80 mile diameter, and only small 1 KW towers to cover it, on one frequency channel. Even with COFDM at 1/4 GI, a passive system won't work (28 mile spacing max). So, you say, use fewer and more powerful sticks, all clustered closer together. Aha, like the Berlin system. And then you lose the sharp boundary delineation. Get it? The way to solve that problem is to use a big stick, then use the small guys as gap fillers. The reason that works is that the repeaters' signals, if designed correctly, will be swamped by the big stick's signals when they otherwise would have been interfering with another small stick. This makes the whole system much easier to build, with no need for synchronization. So, why not consult with someone you trust? Someone who understands how to build these things? I even quoted you from the French TNT technical report. How is it that none of this phases you? Bert ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways: - Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word unsubscribe in the subject line.