Join Date: Aug 2009
Location: Beaverton, Oregon
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ATSC 3.0 is likely do better than ATSC 1.0 to provide service in the fringe. It uses an OFDM modulation scheme that involves sending many tightly spaces carriers that is easier for receivers to demodulate in difficult situations. Beyond that, I am uncertain. The ATSC 3.0 standard allows a wide range of transmission characteristics allowing the broadcaster to choose to send a low data content signal that is very easy to decode, to a very high data content signal that requires a larger signal to noise to decode than ATSC 1.0. In fact the low data mode of ATSC 3.0 was specifically designed to be received by hand held receivers in moving vehicles.
I have read some accounts that say it is possible for the broadcaster to do both at the same time. I don't know myself as I have found the ATSC 3.0 physical layer document to be opaque. It never plainly gives the over the air characteristics of the signal. I am sure it does exactly specify the signal but it uses a mental model that I do not understand. I am old, so perhaps a new specification format/concept is likely to be difficult for me; but I have heard similar complaints from other, younger, broadcast engineers also. Having ended my career with learning and designing for ATSC 1.0, I understand its physical signal fairly well. It was a wonder in it's day, but it does have limitations when it comes to being decoding when multipath is bad and/or signal strength is low.
No one has asked, so I will just volunteer that the avatar that is associated with my AVS account is the ATSC 1.0 system impulse response (i.e., transmitter and receiver combined) expressed in a polar format. It is very different from normal QAM because it is a vestigial sideband system like analog TV. As far as I know, I am the only person that has displayed that signal's characteristics in this polar format. For my own amusement, several years ago I wrote an (unpublished) "learned" paper about the physical ATSC 1.0 signal writing down what I knew. This was well after ATSC 1.0 was well adopted so no one seemed to be interested in it. Write me if you would like so see it.
Last edited by LinleyG; 07-01-2018 at 02:31 PM.
Reason: Removed a line feed before word "Having". Changed wording slighty to make it clear there are many transmission modes,