Data transmission of UARTA in Piksi GNSS module for RTK technique without using radio

[GUN HEE KOO]

Hello.

I am in a research project group with a purpose of developing a bridge monitoring system using piksi modules.

So we have implemented a lot of experiments with piksi modules and other sensors.

And now we in the step of developing a monitoring system including multiple piksi modules since we have verified a data fusion technique using piksi data and other sensor data.

In the middle of system development, we concluded that the use of radio for communication from base to rover is not adequate for about 7km distance with some obstacles.

Instead of radio, we tried to use LAN-wired local network with UDP.

Until now, I have checked about 12 bytes of data are generated from UARTA in a second. 

So I transmitted 1 byte data in 12 times in a second from UARTA of GPS base to UARTA of GPS rover, and it means when the 1 byte is generated from UARTA of GPS base, then the message is transmitted to UARTA of GPS rover, because I don't want to make a problem related to transmission latency.

But this method doesn't work. Any valid Baseline_NED data have not been generated from GPS rover.

Also we have found some message types from UARTA of GPS base. They were not the type of SBP message.

In summary, what I want to know are three things

1) What is the problem in mentioned data transmission method. 

2) For RTK technique without radio communication and adopting LAN-wire communication, what procedures need to be implemented? (Considering that I am not familiar to device communication, please answer kindly and concretely.)

3) Additional to SBP message, are there other message types generated from UARTA?

Thank you.