Are HD receivers resistant to ghosting from multi-path?

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Some people seem to be getting by quite well with indoor HD antennas.

Does the digital encoding of the HD signal allow HD receivers to do
some sort of processing to reduce the effects of multi-path?

--
Bert Hyman | St. Paul, MN | bert@visi.com
 
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Bert Hyman wrote:
> Some people seem to be getting by quite well with indoor HD antennas.
>
> Does the digital encoding of the HD signal allow HD receivers to do
> some sort of processing to reduce the effects of multi-path?
>

ATSC receivers do provide processing for static multipath (ghosts). Some
receivers are better then others; they can provide crystal clear
pictures even when an analog picture is badly distorted due to ghosts.
There are limitations though. My receiver as an example, does a good job
receiving 8VSB transmissions even in severe ghosting conditions. I am
able to receive digital broadcasts from over 100 miles distant; but I
cannot get reception from a digital broadcaster that is only one mile
distant and due north of me. The problem is two fold. Their broadcast
antenna is directional and I am located in their null. I get virtually
no signal when my antenna is aimed in their direction as indicated by a
spectrum analyzer. Second, the signal that I do get is reflected from
the east and is far stronger then their direct signal. On a spectrum
analyzer, their reflected strength is strong enough to permit reception
except for multiple ghosts that are beyond my receiver's ability to
process. There strong reflections from object(s) that are over 4000 and
8000 feet distant. If this broadcaster aimed their antenna in my
direction, I think I could get reception. Also, reception might be
possible with the newer receiver designs. The 5th generation Zenith
receiver is claimed to provide superior reception over the older
receivers for processing multipath.
 
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On 20 Dec 2004 15:40:15 GMT, Bert Hyman <bert@visi.com> wrote:

>Some people seem to be getting by quite well with indoor HD antennas.
>
>Does the digital encoding of the HD signal allow HD receivers to do
>some sort of processing to reduce the effects of multi-path?

I can only speak for this newer Dish 811 receiver im using. I live
about 75 miles from the TV stations. The signal has to cross through a
valley 65 miles away. Their are also 4500 foot mountains with steep
cliffs only 4 miles from where we live.

The digital picture is perfect with absolutely no ghost. Fox had
ghost till about a month ago. I noticed they boosted their digital
signal from 81% to 93% (on screen indication)

My understanding of the digital receiver is that if it sees a
multi-path it chooses the strongest signal and applies it to the
outputs.

The 811 shows Fox's analog channel to be 14.1 and 14.2 I can
understand ghosting with the VHF channels due to the long wave,
especially down on channel 2. I would think the UHF band would
minimize that even on analog.

Im using a Winegard PR-8800 (8 bow tie) UHF antenna up 30 feet from
the ground. The pre-amp is also by Winegard (25 db) mounted at the
antenna. RG-6 coax is 180 feet long running to a two set splitter
that runs to two Dish 811 receivers in separate rooms.

hdtvfan