NTRIP + Rover vs. NTRIP + Base + Rover

Reach Module / M+ / M2 Getting started
1

Hi all,
is there any advantage or disadvantage in using:

  1. NTRIP corrections directly with the Rover (no Base) and

  2. NTRIP corrections to the Base which then corrects the Rover.

Would it make any difference in open areas, e.g. open fields? How about if the Base is set up on an open field and the Rover is measuring under Trees?

1 Like
2

Ntrip is a way of sending correction from one unit to another.
So i am not sure what your question really is.
Q1: You would still recive correction that would be similar to a base (VRS etc)
Q2: Depending on baseline and features available, you most likely benefit from having a base close to your rover.

1 Like
3

The ROVER has to have good clear sky view also, especially Reach RS/RS+. Itā€™s not like the BASE (with clear sky view) helps by coming in sideways to the ROVER via a tunnel etc.

The RS2 apparently is what you need for working in and around tree canopy etc.

4

Hi Tim ! Could you explain what a VRS is?

5

Simply put, your just using someone elseā€™s BASE over the internet connection (as long as not too far)(like CORS, RTK2GO etc) versus just using your own BASE via LoRA which I personally prefer.

Hereā€™s some good reading:

https://www.google.com/amp/s/geohubkenya.wordpress.com/2017/11/15/difference-between-cors-and-vrs/amp/

4 Likes
8

Can anyone clarity, if I set up my base up to receive corrections from an NTRIP via my cell phone with fix and hold for say 5 minutes, wait for a fixed solution then start recording points. Do I need to leave the phone close to the base so it continues to receive corrections or will the base hold its base location coordinates after the 5 minutes has elapsed? ( Iā€™d be using a tablet as a controller so could leave the phone near the base if I needed to)

1 Like
9

If you average fix for say 5 min then it save those corrdinates then thats all you need.

Yes

10

Seems you would need to record the AVERAGED FIXED (not AVERAGED SINGLE) position received from your NTRIP station. Manually save that position. (Antenna height 0) Mark the spot the base is set on with rebar etc. Then go on your way. I do not know if you need the cell phone to stay there, but assume you would NOT need to leave it nearby to be stolen with your base while away. Better get someone to stay with it.

11

Thanks for the replys, thought if I needed to leave it close to the base I could lock it in my vehicle within range of the base. If the corrections from the NTRIP are accurate and the base is left to average for 5 minutes then the base coordinates should also be accurate, just wasnā€™t sure if the base lost connection to the NTRIP would it begin a new cycle again or stick with the coordinates it averaged. One sure way to find out I suppose!

2 Likes
12

Hopefully someone that uses NTRIP a lot can give you a straight answer. ; )

13

If you are averaging your base coordinate:

  • A Reach device acting as base will average its base coordinate right after it boots up.
  • If you havenā€™t set up your NTRIP connection yet or need to adjust the averaging method/duration, then you can click the button to refresh the base coordinate and restart the averaging process.
  • Any averaged base coordinate will be saved until next boot.
  • The displayed base coordinate will be transmitted in the RTCM3 messages to any rovers that are listening.

You should only ever average a base coordinate once. If you intend on ever using that base location again, then record the base coordinate after it has finished averaging and next time you use that base location enter the coordinate manually.

2 Likes
14

Thanks guys, thatā€™s exactly what I was hoping. Iā€™ll give it a trial run in the garden before I take them out again.
if I set the base over a fixed point say a steel pin or nail, write down or record the coordinates then next time I set over the same point, enter the base coordinates manually, should leave me on the same grid allowing me to stake out or survey more points

3 Likes
15

https://docs.emlid.com/reachrs/common/reachview/base-mode/#base-position

more reading as the antenna height, known point, averaged point gets confusing:

1 Like
16

This topic was automatically closed 100 days after the last reply. New replies are no longer allowed.