Quick update.

After the initial version was made, I found a few minor issues. All issues are resolved in V1.2

• Added battery charging functionality, so you can use this module with 3.7V LiPo battery powered. It handled by MCP73831 chip. JST 1.25mm 2P is used  for battery connector.
• Change PCB color and tidy up top silkscreen 2x13P connector

Results so far :

• PCB assembly succesfully, and quite easyly done by hand-soldering
• Upload code done using Arduino IDE
• Two Way Ranging tested perfectly in indoor, but for some reason the zero distance reported as 30cm. Maybe need to calibrate the antenna.

Please take a look the project github link for the schematic, gerber file, and sample code for the current mile-stone.