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Survey Locations Without Line of sight?

Survey Locations Without Line of sight?

Survey Locations Without Line of sight?

(OP)
Is it possible/feasible to use radio transceivers to calculate locations over short (less than 1,000 feet) distances even when the line of sight is obscured by brush? The radio waves penetrate the brush for radio communication so why not location data. What I am trying to get is good relative locations. I notice that surveyors using a total station will often run a reflector way up on a pole to get line of site from their station to say - wetland flags obscured by brush . That technique introduces some error anyway so why not make it easier? I currently use a infrared rangefinder and two cylindrical reflectors and shoot distances to each reflector from each point. Where the circles of the respective radii cross in cad is where the point is relative to the others. I rotate that into a drawing with registration points like property corners, intersections. The technique works great for what I am doing - preliminary measurements of ecological features and determining buildable areas etc. but, line of sight is required. GPS is too inaccurate at that scale and requires a line of sight to the satelites.

Basically, I want to have a portable LORAN-like system of my own that can give me fairly accurate relative locations over short distances and be operated  by one person. Is that too much to wish for?

RE: Survey Locations Without Line of sight?

GPS that uses a base and a remote is plenty accurate enough. Survey grade GPS is capable of accuracies of +/- 0.01 Northing & Easting and can be operated by one man. Just put the GPS remote on an extended 10 foot pole to get out of the brush.  The remote unit only needs a line of sight to the satellite if the base is also setup on a monument or control point that is brush free.  It is trees that will normally cause you problems with this setup.

LIDAR will also read through the brush.

RE: Survey Locations Without Line of sight?

They used to call surveyors 'brush apes' for a reason.

Richard A. Cornelius, P.E.
WWW.amlinereast.com

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