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Interference from airport
TL:DR, can airport instrument landing systems or localizers interfere with observation collection?
First off, I’m not a surveyor and have had no training besides a bunch of forum searches and YouTube videos. I just use a Nikon total station and Reach RS2 base/rover to take shots and engineer pipe bends for pipeline construction. So I won’t be using the correct terminology all the time here.
About 4 years ago I started using the Reach system and mostly used CORS to set my base, but where CORS isn’t available I use OPUS to get my base point. Every time I set up I’ve been collecting observations and uploading them to OPUS to get a solution so I can compare my OPUS uploads to the base point gathered from CORS. About 95% of the time I’m within 1 to 2 cm, and in that time I’ve gained enough knowledge on how to pick a good base location for collection.
Last month I was in Michigan and set up on the same spot and gathered base data on 3 separate occasions over a two day span, all in excess of 4 hours. Several days later I uploaded the observations and all were aborted.
The other day I was back up on another location 3/4 mile away and got a good solution when I uploaded the observations. I was within 1.5cm of the CORS point, and would say that it didn’t have as good of a clear view of the sky as the other base point.
I had to go back to the first site and stake out some ditchline and recorded the observations, and again I got the aborted message.
Trying to figure out what I had done wrong I got to thinking about other possible outside interference and remembered that every few minutes a jet was directly overhead, landing at the airport.
I pulled up Google Earth and saw that I was 2.5 miles from the touchdown point and 150′ off of the centerline of one of the runways.
Could the ILS or other equipment cause an issue with any part of the observation?
Thanks
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6 Replies
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I have definitely had RTK interference that prevented getting a “fix” around enough airports to ascribe the problem to something associated with certain areas of airports, but I have never been able to find out just what exactly was causing the problem. It doesn’t suprise me that you night be experiencing something similar with static collection.
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Do you have to collect static for OPUS? So much time. If you have 2 RS2/+/3 receivers, you can use LoRa to send cm level corrections from the base to the rover and use control points and localization (site calibration). Are your designs in state plane or something? Or assumed coordinate system… i.e. 1000, 5000, 100
Maybe use a portable Spectrum Analyzer to see what interference is present?
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We do both static and RTK surveys on a regular basis on and near 3 airports. We have very few issues with getting great results from this work. Some of these are within 100′ of the emitters (radar/VOR/localizers). I can’t imagine that if you are a few miles out that you would see any interference.
—Dan MacIsaac, PLS -
I am not an expert on GNSS equipment. That said, we have been having a lot of solar activity the past few months, and I know that in addition to the pretty aurora borealis displays this can wreak havoc with the navigation satellites’ radio signals. Have you looked into the possibility that the space weather messed up your observations?
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I would also consider the solar activity as an issue. We usually use CORS but this year we’ve been using more and more base/rover setups to mitigate the effect the solar activity has been having on our GNSS equipment, especially in the woods.
It’s been a while since I’ve needed to run anything through OPUS (we’re in the northeast and have multiple CORS to switch between) but I always found it very finnicky. Entirely possible overhead jets could be giving multipath errors?
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Use the Total Station if just can’t get around it.
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This reply was modified 1 month, 3 weeks ago by timd1971.
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This reply was modified 1 month, 3 weeks ago by
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