Control RTCM messages from Piksi Multi base

GPS / RTK / GNSS
1

I’m using the GNSS receiver & antenna from my SwiftNav Piksi Multi dev kit as my base station and working on setting up a RTK correction network with Digi SX radios. If I would use the lowest RF Data Rate then I get much higher receiver sensitivity and useful range out of the radios. Set to output RTCM MSM4, my base outputs msgs 1006, 1008, 1033, 1074, 1084, 1094 & 1230. 1230 is sent twice, is that normal? From what I read it’s probably not even needed but I can’t turn 1230 off.

I did some throughput testing and at the lowest RF Data Rate, Digi’s XCTU Throughput test shows 4-5 kbps and looking at the RTCM data with SNIP’s RTCM3 Message Content Viewer it looks like I need about 4 kbps at 1 hz RTCM output.

Now, I don’t think I even need 1 hz RTCM data, every 2 or 5 or maybe even 10 secs should be fine but I notice that if I lower my base’s RTCM data output rate, msgs 1006/1008/1033 (base station details) still get sent at 1 hz and only the msgs 1074/1084/1094 (gps/gno/gal constellation data) are slowed down. This is the opposite of what would be useful as msgs 1006/1008/1033 don’t change and shouldn’t need to be transmitted more then a couple times a minute whereas the constellation data actually matters. It also appears as though the msgs are sent in bursts whereas I wonder if it would be better to transmit at a slow & steady speed, maybe 1 msg per second for the constellation data (3 constellations = 0.33 hz) and every 5th cycle add the base station info msgs.

My base station only offers MSM4 or MSM5 for RTCM output. According to this site from Novatel, MSM5 only adds doppler information but it increases the size of the important satellite measurement messages by 31% according to SNIP’s RTCM Viewer, it’s working with MSM4 so I’ll stick with that.

Can the ESP32-XBee base station code filter and slow down the msg rate?
ESP32-XBee
or rtkbase
or this Arduino library

2

Hello,
I am also on the problem, because I would like an nprip client with the possibility of filtering the msg.

in my case I have a lora radio with Caster (several messages), I use STRSRV to filter:
RTCM 3 to RTCM 3 with message type 1005 (30), 1074 (1), 1084 (1), 1194 (1), 1230 (30).
and it works very well about <5 kbps.

I am testing this schema: ESP32-XBee (client) → arduino (filter) → radio
i saw the arduino library but i can’t get it to work.

I am testing based on this code rtcm3add1008.
but I cannot manage the storage in the buffer well.
on the principle:
if (type == 1005 || type == 1074 || type == 1084 || type == 1094 || type == 1230) {
mySerial.write(buffer)
}
I do not metrise, and my arduino is not working well.

I am also a solution taker.
I don’t think ESP32-XBee does filter.

3

Strsvr does enough for me at the moment. I think I’ll switch to using RTKLIB on a Linux VM instead of SNIP on Windows.

4

Are you using your piksi multi base with Ardusimple rtk2B rovers?

5

Yes, exactly

6

I am getting ready to do the same thing does the standerd rtcm output from piksi work with the rtk2b?
I guess was wondering what messages you are sending out to rtk2b

7

In your experience can default rtcm output from swift work withrtk2b

8

I’m using “RTCMv3 OUT”

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image1250×312 39.3 KB

It sends MSM4 (1074, 1174 etc)

Yes it works with F9P

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