Can I use Reach RS Base & Rover without internet access?

Let’s say I am in a remote area, no 4G, no hotspot for internet. Just the Base and Rover with LoRa.

I just need to stake points based on 2 known control points.

Will I still be able to get decent accuracy? If enough good satellites, clear sky etc etc obviously. Or just get sub meter or worse accuracy like what’s in cell phones these days?

I really need cm accuracy, but wondering what to expect without internet for corrections. Or is internet a requirement?

Is there any general documentation showing how to set up Base & Rover without internet but just relying on themselves and the satelites? Do I have to create my own network with portable router or can they work as their own hotspot I see as a setting in ReachView?

Thank you for the help. Still learning and reading up every chance I get.

If you know the position of one of them, then you would be ok, cm accuracy.
If you`re in the midle of nowhere, you need a different approach. Either PPP (30-40cm accuracy) or VRS service (1-2cm accuracy but requires internet connection) Or a long range static approach (PPS), like PPK but post processing static (you lose accuracy of 1mm pr km)

Your relativ distance between base and rover would give you cm accuracy with and up to 10km baseline. Now, if LoRa is able to send correction this far depends om the location and obstructions. Other option would be a repeater, better antenna, different radio or do some of the options mentions above (VRS). I guess PPP would not cut as it would only give you 30-40cm absolute accuracy. But if you looking for cm relativ accuracy baseline and can make do with half a meter accurate world coordinates, then PPP is a good choice.

Here
https://docs.emlid.com/reachrs/common/tutorials/placing-the-base/
and here
https://docs.emlid.com/reachrs/common/reachview/base-mode/

Edit: I saw few typos in there that could be misread.

Also if you dont have cellular coverage, internet through satelite is an option. Comes in different solution, from large disks to small handheld devices (ref VRS option or long range RTK)

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To my knowledge from experimentation with different datasets, PPP can give you even down to millimeters in absolute precision.
But of course this requires 12-24h observation time, and 2-14 days delay to get “rapid” or “final” processing.

But given you have 2 known spots, you should be good already?

With L1?

No, that was indeed with a L1/L2 receiver, but GPS only. Wasn’t aware that L2 would improve it that much.

Yeah, the L1/L2 in PPP handles atmospheric conditions better. Or to not be mistaken, L2 “rules out”
L1 atmospheric errors as i understand it.
But some PPP decimeter accuracy rumors with L1 is out. Actually, its been out for years but i recently found it and trying it out now

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So if I just have Reach RS Base and Rover using LoRa, I can stake out cm accurate points? DO I even need to consider “corrections” then…couldn’t anyways without any outside connection to do so… so just wondering if “corrections” are a “requirement” to get cm accuracy… or do all I need is LoRa (which is awesome if so).

I basically just need to work within a “rectangular area” starting as XY origin and work my way out from there. I may have to work radially also, but to keep it simple for now, just XY origin. I guess I would need to set my origin somehow in Base Mode on the Base unit correct? Can the Rover just work relative to the Base this way?

So if I have no internet, no wifi, no 4G etc etc… just sole Reach RS Base and Rover.

I am not using the Reach RS units for surveying, just staking / laying out points from a DXF etc file.

Thank you for the help… I am getting a lot of this, but some things still baffle me… especially corrections…but I don’t need corrections for my application…no need to worry so much about it…but wan’t to make sure everything is proper so I don’t have a problem later due to ignorance.

Thank you!

Yes

You do correction when you have rover connected to base or similar, If not then you will not get cm accuracy with Reach.

LoRa is just one way of sending stuff from one unit to the other.

To me it sound like you only need relative accuracy and you get that by having base sending satellite observation to rover so it can calculate the differential from its own observation. Differential correction.
Your origin doesnt have to be at the base, it could be anywhere. Like in any CAD software, you could move/set your own origin and work from there.

The term correction or differential correction is just a way a single gps can reduce error introduced in the atmosphere. It has nothing to do with relative or absolute positioning. Read this
https://www.e-education.psu.edu/natureofgeoinfo/c5_p23.html

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[quote=“TB_RTK, post:8, topic:10038, full:true”]

Yes

You do correction when you have rover connected to base or similar, If not then you will not get cm accuracy with Reach.

Ok, I guess I a still confused with the 2 statements above. 1st statement I assume I can get cm accuracy with ONLY Reach RS Base and Reach RS Rover (using ONLY LoRa).

But then 2nd statement says NO cm accuracy if Reach RS Rover not connected to Base…but it will be connected to Reach RS base via LoRa? sorry, confused…

LoRa is just one way of sending stuff from one unit to the other.
(ok, I follow you there. Like BT, just sending data is all. I was thinking that just using Reach RS Base & Reash RS Rover and on LoRa that somehow it can give me cm accuracy without the satellites, internet, corrections etc.)

I will read the link you provided about corrections.

Thank you for your help and patience with me. ; )

Ok, so if you have LoRa connecting rover and base you are getting cm.

you need visible satellites, and connection between rover and base to do RTK cm measuring.
:slight_smile:

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ok, I see. Thank you. ; )

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