DTV In motion op's

[Y2k06]

I was pondering the idea of putting a DTV converter in the SUV using the composite inputs and using some sort of mobile antenna mounted on the front and rear window.

Was mentioning this to someone and they laughed and said WILL NOT WORK.

Added by saying the DTV signal receiver / antenna has to be fixed - not moving, similar to a satelitte dish to be able to receive and decode the signal?

Got to thinking about it and would seem just the oppsite from analog. Isn't the sky being bombarded by Digital signals? Simlar to XM radio, for example?


Does this sound right and if so, why?

 

[boba]

Winegard Metrostar omni directional TV antenna maybe what you need for on the road RV reception. I would expect a lot of digital dropouts while in motion.

 

[meinename]

The word you are looking is multipath. And Doppler shift...

Multipath is the ATSC-standard's crutch.
[ame="http://en.wikipedia.org/wiki/Multipath_interference"]Multipath interference - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/Filehase_shift.svg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/5/55/Phase_shift.svg/220px-Phase_shift.svg.png"@@AMEPARAM@@commons/thumb/5/55/Phase_shift.svg/220px-Phase_shift.svg.png[/ame]
[ame="http://en.wikipedia.org/wiki/Doppler_shift"]Doppler effect - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Question_book-new.svg" class="image"><img alt="Question book-new.svg" src="http://upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png"@@AMEPARAM@@en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png[/ame]

They have a proposed standard, ATSC-M/H (A-153)
But it's all still prototypes right now
ATSC-M/H - Wikipedia, the free encyclopedia

 

[Jim5506]

Unless he approaches a small fraction of the speed of light, doppler shift should not be a problem.

 

[Y2k06]

Thanks for the explanation of some of the technical terms.

Question remains, will DTV reception on a moving vehicle be better or worse than it was with analog TV?

My options for antenna are for maybe a 'boomerang' type or internal radials on front and rear glass.

 

[boba]

I expect it would be worse than analog. You would probably need to be within 30 mi. from broadcaster to have a signal. If driving through a city buildings would cause multiple reflected signals.

 

[CowboyDren]

It's just not going to work. A good antenna on a fixed mast that sways too much (in a heavy storm, for example) causes picture dropouts with ATSC. You just have to wait for the FCC to approve a mobile technology and for manufacturers to support it.