Sat Comms Antenna Update

Testing of the satellite communications has proceeded over the past couple of months in different circumstances. 

Australia is in the Band 255 region for the Skylo NTN service. This band is close to the GPS L-Band.

I've had reasonable success using a passive GPS Patch antenna with the Murata 1SC NTN module

But reliability for telemetry was only adequate. In practice, around 1 message in 3 may be lost.

I purchased a low-cost PCB Antenna intended for use with Inmarsat through AliExpress.

This antenna is intended for the Band 255 L-Band.

This yielded significantly better performance than the passive GPS Patch antenna.

It is larger, but being flat it does not occupy much volume.

Inmarsat PCB Antenna sold through AliExpress for under $10

The SMA Connector is mounted on the top of the board. I moved it to the underside of the board to allow the PCB Antenna to be placed against the top of the interior of the equipment housing, occupying the minimum amount of space.

Inmarsat PCB Antenna installed within the Equipment Housing

On water tests have been limited. But so far results are good, with zero lost messages with reporting every few minutes over several hours.

On water testing - good results so far.