Reach RS and Reach M+ connections

Hi all,
I am planning to use Reach UAV mapping kit for more accuracy. Firstly, I connect to Reach Rs, and set up like image below.


After waiting for coordinate accumulation, I connect to Reach M+, and set up for Input like image below.

However, when I moved Reach M+(Rover) far away Reach Rs(Base), the GPS of rover no changed any more. It’s location on the map till near Base.

Could you show me my error there? And any solutions. Thanks in advance.

Hey there,

Could you please share your Reach units system reports?

What was the baseline between base and rover when you’ve had a connection issue? Please take into account that Reach hotspot won’t give you a long range for RTK communication.

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Your problem lies within the address you entered, which is:192.168.42.1

I also see that you have TCP selected for receiving base corrections. Does this mean that you intend to pass corrections directly over Wi-Fi, or do you have some cellular modems or other networking setup.

Lastly, please explain how you have the Wi-Fi set up (which devices are the host/hostpot and which devices are the client, and also the network addresses of each.)

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Hi Bide,
First, I connected my phone and Reach RS via WI-FI of Reach RS, and setup Reach RS as a server.
Then, I connected my phone and Reach M+ via WI-FI of Reach M+, and setup Reach M+ as a client.
The network address of both Reach RS and Reach M+ is 192.168.42.1

Hi Tatiana,
This is the report from Reach device.
The baseline between base and rover is always small (0.1-1)SystemReport[1].zip (108.2 KB)

It’s like they said, when using the hotspot of 192.168.42.1 to connect the two (EDIT: this is incorrect, see bides response. They are on their own hotspot), you’re limiting your range between the two to send corrections from reach rs base to reach m+. That range will be extremely short like probably 50-75 feet or so?
It’s not meant to work the way you have it set up this way.

The problem you are facing is that when a Reach device is in hotspot mode, it is creating its own network.

Since each Reach device is on a separate network, that is the reason they can both claim the identical IP address. They are on isolated networks and have no way of communicating with each other. You know this because you must connect to one Reach Wi-Fi network or the other in order to access them.

Then, by setting Reach to receive corrections on 192.168.42.1, all you are doing is telling it to receive corrections from itself. It will never appear to move because it is always being corrected back to its current base coordinate. It is a feedback loop.


So, if you wish to perform RTK and continue to send your base corrections over Wi-Fi, then you will have to fix your Wi-Fi configuration and get them both on the same network. But as @timd1971 mentioned this will allow for only a short baseline. It will be enough to do some testing or perhaps a survey a small area. Is that your goal? Or do you wish to do medium and large areas?

Also please confirm if your goal is to do RTK or PPK surveys.

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Firstly, my goal is test the accuracy of Reach with some national ground control points. Then, if the result is good, I will use for mapping with high accuracy. My purpose is to do PPK survey.

OK, if you are going to be doing PPK then you don’t need to set up base corrections because they are for RTK.

You can review this guide:

But the basic needs for PPK data collection are:

  1. Select the GNSS systems you want to use (constellations).
  2. Select the sample rate (the update frequency in Hz).
  3. Make sure the raw data log is turned on.
  4. Optionally, you can select a RINEX version for the automatic raw data log conversion.
  5. There is no base and no rover for PPK. Configure all your devices the same. Later during your post processing you choose which one is acting as base and which one is acting as rover.
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Thanks for your post.
How about set up for Reach M+? Is the same?

Yes, see item number 5 above. I just added it to the list.

I have one more question. How to setup for RTK servey?

Sure. For RTK survey, you need communication between base and rover. If you purchase two RS+ units, then that is normally done over LoRa radio. If you purchase M+, then it is assumed that you will provide your own communication path. e.g. UART radios, cellular modem, high-powered Wi-Fi, or a nearby Wi-Fi network with internet access (smartphone hotspot), etc.

If you just want to play around and test in a small area, then you can continue with what you were initially doing. But you need a common Wi-Fi network. Do you have a Wi-Fi network that both devices can be configured to connect to? Perhaps a hotspot created by your cell phone or tablet, or maybe a Wi-Fi router?

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I have a Reach RS+ which is used for base role and a Reach M+ which is used for rover role. I want to test in the small area first, before doing in the large area. The wi-fi network is not my problem when I can use phone’s hotspot or wi-fi router.

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OK, perfect. Just configure both your Reach devices to connect to one of those networks. They will be given IP addresses in the same subnet and they will be able to communicate with each other. Use the ReachView app to find their IP addresses.

If you have any other questions, let me know.

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Thanks for your help.
I will test in the morning tomorow.

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Hi bide,
The test today completed with good results of both RTK and PPK surveys.
Additionally, with RTK survey, we can use wi-fi network of base. It means that, we connect both of mobile and rover devices to wi-fi of base. However, it is only suitable for small area.

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yup, you’re confined to the limits of the HOTSPOT of the unit(s) or even if you connected to a wifi router it may help some for area or range, but really, if 4G cellular available, you may want to look into connecting to a WIFI HOTSPOT of a 4G cellular device (i.e. your phone’s hotspot or a separate 4G wifi hotspot device). or PPK everything later if RTK isn’t needed (realtime).

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Good experiment. Thanks

Hi Bide.

Is there a way to connect two reach RS antennas via tcp if each one is on a different Wi-Fi network?.
I have used a mobile modem on my base antenna and the wifi point of my phone on my rover antenna to receive ntrip fixes (rtk2go), works for me.

But I want to know if it is possible to send the corrections directly with tcp.