Configure RKT
step1 use wired connection, visit the fixposition web page
step2 RTK requires a network connection
step3 Log in to the RTK account (the configuration must be successful when there is a GNSS signal)
The connection is successful as shown below
u-center acquires satellite data
Here we connect through TCP
Here 20010 and 20020 respectively correspond to the data of the two antennas
Click here to display the output text in the form of text. The 
above fields respectively represent:
$GNGGA,131547.30,3908.17889767,N,11715.45111804,E,1,14,1.7,18.282,M,-8.614,M, ,*54
Field 0: $GNGGA, statement ID, indicating that the statement is Global Positioning System Fix Data (GGA) GPS positioning information
Field 1: UTC time, hhmmss.sss, hour-minute-second format
Field 2: latitude ddmm.mmmm, degree-minute format (leader If the number of digits is insufficient, add 0)
Field 3: Latitude N (north latitude) or S (southern latitude)
Field 4: Longitude dddmm.mmmm, degree-minute format (if the leading digit is insufficient, add 0)
Field 5: Longitude E (east longitude) or W (west longitude)
field 6: GPS status, 0=not positioned, 1=non-differential positioning, 2=differential positioning, 3=invalid PPS, 6=estimating
field 7: number of satellites in use (if the leading digit is insufficient Supplement 0)
Field 8: HDOP horizontal precision factor (0.5 - 99.9)
Field 9: Altitude (-9999.9 - 99999.9)
Field 10: Height of the earth's ellipsoid relative to the geoid
Field 11: Difference time (difference time since last received The number of seconds from the start of the signal, if it is not differential positioning, it will be empty)
field 12: differential station ID number 0000 - 1023 (if the leading digits are insufficient, fill in 0, if it is not differential positioning, it will be empty)
field 13: check value
Analytical data
Refer to the link
ROS to realize the analysis and communication of serial GPS data