Release Notes
ATOM UAV MANUAL 
Date: 
2022
-
01
-
04
Version: 1.3
Page: 10 of 39
FLARM Technology 
Ltd
Hinterbergstrasse 15 
CH-6330 Cham 
Document Number: 
FTD-088
Note:   Communication  between  FLARM  devices  employs  an  encrypted,  patent-
protected protocol. Any unlicensed use, copying, distribution, conversion, 
replication,  access,  interception,  de-compiling,  reverse  engineering,  or 
further  transmission  of  knowledge  so  acquired  relating  to  the  system 
components or software/firmware, in whole or in part, is thus illegal. 
3.3.1  RF Connectors 
Atom UAV uses MCX connectors for all RF interfaces. The corresponding connector 
can be identified as GNSS, ADS-B and FLARM on the device housing (Atom UAV 
standalone variant) or on the PCB next to the connectors (Atom UAV OEM variant). 
The Atom UAV OEM variant additionally has a U.FL connector for a Wi-Fi antenna. 
3.3.2  Placement 
For good performance of the FLARM system, the FLARM antenna must be placed 
at least 20 mm from larger pieces of conductive materials such as a metal surface. 
The FLARM antenna must be installed vertically (perpendicular to the horizontal 
plane). 
If the aircraft body contains large amounts of conductive materials such as carbon 
fiber, the antenna must be placed outside the vehicle body. If the selected antenna 
location does not give clear line of sight in all horizontal directions, two Atom UAV 
devices  can  be  mounted  to  increase  the  coverage,  using  the  radio  diversity 
functionality described later in this document. 
For good performance of the GNSS receiver, the GNSS antenna must be placed 
such that signals from the sky are not obstructed. The antenna should be mounted 
on a sufficiently large ground plane, either as part of the host PCB or on a separate 
metal plane that adds more than 20 mm of ground around the antenna. 
Due  to  the  larger  transmit  power  of  the  ADS-B  system,  the  placement  is  less 
crucial. However, the antenna should also be installed vertically and be placed at 
a sufficient distance from conductors. 
Note:   Atom UAV also receives and decodes Mode-S signals, which do not contain 
position information. Instead, the distance is estimated from the received 
signal strength. The radiation pattern of the ADS-B antenna installed on 
the aircraft should be omnidirectional to give accurate range information. 
Due  to  limitations  in  the  MAVLink  protocol,  Mode-S  targets  are  not 
available on this interface. 










