What to do about heavily wooded sites?

PP is something everyone should learn, whether it’s Emlid Studio or a commercial software such as “Javed Justin 3”.

Short baselines (on project site) along with adequate observation time on station are your friends. Long baselines = longer observation times. PP with closed GNSS traverse loops or terrestrial traverse loops is the only method to truly know and verify your “fix” in high multi-path areas.

When I’m able to go out in the field, I usually have both my M2’s as base receivers with a baseline between them usually <1km. I’m using my RTN rover locating points (property corners, creeks, roads, etc.); I have a closed GNSS polygon for each point whether I have a “fix” or not. Baseline lengths from the rover to the base receivers depend on each project site; usually anywhere from 50 meters to 2 km.

We have Javad equipment here, I’m usually using my Javad rover and base M2’s with the state RTN. Even though I may have a “fix”, I’m always saving my raw data at the rover whether in the woods or not. We use our Javads in high multi-path areas, they are the only receivers that can verify a position in high multi-path areas. These receivers are very expensive, >$20k. The Javad receivers have paid for themselves on various small and large projects due to their ability for the user to have high confidence in point location while in multi-path areas.

I’ve used my RS2 and M2’s in high-multi path areas and have gotten “fixes” on points; I’ve always revisited these points when using Emlids receivers. I’ve gotten bad and good results in the woods, but I always have the raw data to PP with my M2’s on site. It’s always amazing when verifying the “fixed” field shots PP. Some “fixed” Emlid points have agreed fairly well when PP; <2-3 cm horizontal and vertical. Others not so well, but I have the raw data to PP and to determine the true location. It’s always fun verifying false “fixes”, closed project site GNSS loops usually have closures in excess of 1: 50,00; depending on the length of the baselines.

I’ve said this many times on this forum:

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