I needed a simple portable node that would repeatedly broadcast its location using a connected GPS so I could make range measurements.
I used a Moteino board with an RFM69HW RF unit and uBLOX Max 8 breakout board. The uBLOX serial connects via a sofwareSerial using Arduino pins 3 and 4.
I started with the standard UKHASnet sensor code and added the tinyGPS++ library to parse the GPS data plus SoftwareSerial to handle the GPS serial connection.
There are just two new functions, one to parse the GPS data and create a new value for LOCATION_STRING - gpsLocate(). The second function updates the GPS coordinates - smartDelay(ms)
The code should work on any Arduino based node providing you set the right board type in the IDE.
The hook into the location setting is a bit crude so needs tidying up probably with #ifdef
You can find the code here: https://github.com/ptamike/UKHASnetGPS_sensor_node/