There are some fundamental DTV delivery concepts that have been producing misunderstandings amongst some engineering circles including the ones I belong to.

Please understand that these are a snap shot at this time of my own opinions and are offered only as topic points for further discussion. No offense is meant to be issued to any one. I reserve the right to be wrong and at the same time welcome being corrected where I have gone astray. I do not portend to be an expert on anything, I am just an engineer in the trenches that has made some observations at one time or another.

Concept A: according to the great plan, the ATSC data stream does not care nor does the ATSC compliant receiver care what (frame rate) profile is being sent to it. What is important is what happens during the approximately 70 nanosecond group of packets and the approximately 50 microsecond frame data rate.

Concept B: You do not need to convert 24 frame material to 60 frame just for the sake of last mile broadcasting. (frame rate phobia) If you have a choice between pretty pictures with some artifacts or pretty pictures with less artifacts which would you choose? Then broadcast that.

Concept C: Opportunistic data encapsulated with the video is not the only data space available. There is plenty of "holes" in the ATSC stream that can be filled with data. There is space for data in the audio packets - without bothering the 5.1 main channels or even the second audio channel(s), there is program related (time sensitive) data space, there is non time sensitive data space, there is as yet unallocated data space and there is even enough room for ATSC reserved (as yet to be announced what they need the space for) space.

Concept D: If you broadcast 1080 or 480 you are doing so within a 50 microsecond group of packets that also have plenty of room for other information to be carried with it. In other words, you are not "filling up" all the bandwidth only when you are broadcasting 1080, but rather you are "filling up" all the band width if you are broadcasting any compliant format.

You cannot send any more or any less information than what will fit into the 70 nanosecond by 50 microsecond group of packets. Also recall that in digital, the quantity nothing is data. In fact that "no data" data is going to be randomized before broadcasting in such a way that it will cost you transmitter power in order to send "no data" information.

Concept E: Data does not have to be delivered in maximum chunks and highest throughput rates in order to be useful. One bit every 70 nanoseconds over the course of a day is a fairly sizeable, over the course of a year it is quite massive. Just think what you could do with two bits...

Concept F: We cannot engineer our way through the digital transition as we have in times past. At this stage we will have to post our requests and suggestions to the manufactures and just hope for the best as the tools develop. It is in our own best interests then as engineers to keep the communications between us open and not to fall prey to marketing hype, vaporware and market share segmentation.

EDITOR'S NOTE:
We've been approached by a firm which makes a device to detect null packets in an existing stream and substitute a properly formatted data packet.