Long ago, shared a similar problem with a SCADA 900MHz link...we ended up installing a two way splitter, two pigtails and two Yagis at about six feet a part...solved the issue...I had forgotten about that... I remember the space and frequency diversity discussions.
Steve...sometimes a little bit of elevation helps. On Thu, Mar 11, 2021, 2:47 PM Steve Jones <[email protected]> wrote: > this is one that was part of a group of similar issues. We had one that is > white paper level multipath. I can tell you the day and time they start the > harvest across the street and the time they finish it. that one we ended up > just installing 2 radios and they swap power supplies twice a year. > > this one is facing west and looking at it the dips begin sharply around > 4pm the last week, around noon the week before. thats about the time it > starts to cool back down, not that its all that warm. its muddy fields so > the surface is soggier in the day, firms up more when it cools. yesterday > was super windy and it didnt do it, probably the soil is dryer. > > IIRC i have her radio right now peaking over the ridge of the roof from > her tower. > > Im planning on going out and putting it on a 12 foot post to halve the > fresnel, sable marginal is better than unstable marginal. > > the first guy i mentioned here is actually a pretty cool case. this > general region is super high iron content in the soil, we have another area > this is really common and their soil samples are really high as well, i > dont know if iron oxide is more reflective han dirt dirt or if certain > circumstances make it that way. or could be whatever causes the soil to be > more iron rich causes it. or soil content could have nothing to do with it. > I had gotten the sample results from a soil testing joint thats a customer, > thought i could figure it out but its one of those things somebody smarter > than me could probably figure out. > > On Thu, Mar 11, 2021 at 3:23 PM Brian Webster <[email protected]> > wrote: > >> Doe this customer have the issue at a certain time of the day? Maybe >> around sunrise or sunset. It may be possible that it’s not multipath but at >> certain times of the year the antenna has a good path to picking up noise >> from the sun and that could be stronger than your AP signal? This usually >> is exhibited on paths that have an East/West orientation. Depending on the >> gain of the antenna it can be worse than others. Think of the sun either >> just above the horizon at sunrise or sunset and the focal beam on the >> antenna is such that it picks up that noise enough to be stronger than the >> AP. Depending on the time of year, tilt angle of the Earth etc., it looks >> like a seasonal issue. >> >> >> >> Thank you, >> >> Brian Webster >> >> www.wirelessmapping.com >> >> >> >> *From:* AF [mailto:[email protected]] *On Behalf Of *Steve Jones >> *Sent:* Thursday, March 11, 2021 1:36 PM >> *To:* AnimalFarm Microwave Users Group >> *Subject:* [AFMUG] multipath on a reflector >> >> >> >> our APs sit between 90 and 110 feet on average in flat terrain so we deal >> with alot of seasonal ground reflectivity issues. We have this one customer >> presenting again with whats probably multipath fading, I had tried putting >> a shield on the bottom half of the reflector once out of curiosity. It >> didnt do much >> >> what im wondering though is how the ground reflected multipath feeds into >> the feedhorn. >> >> is it reflecting off the top half of the dish and into the feedhorn like >> a mirror? >> -- >> AF mailing list >> [email protected] >> http://af.afmug.com/mailman/listinfo/af_af.afmug.com >> > -- > AF mailing list > [email protected] > http://af.afmug.com/mailman/listinfo/af_af.afmug.com >
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