Rohde & Schwarz R&S ARDRONIS Locate Compact

The R&S ARDRONIS Locate Compact from Rohde & Schwarz (Germany) is a compact detection and direction-finding set on a single mast. It consists of the UMS400 receiver and the ADD207 direction-finding antenna and monitors 400 MHz to 6 GHz for the analogue and digital video downlinks of drones. It can be used stationary on a mast or semi-mobile; the manufacturer names critical infrastructure, military use and police as fields of use.

The manufacturer states that the set detects threats at more than 5 km; the figure is a manufacturer value under favourable conditions and depends on the drone’s transmit power, terrain and radio environment. The receive range of 400 MHz to 6 GHz takes in the connections at 2.4 and 5.8 GHz and the control links at 868 and 915 MHz. Video downlinks, analogue and digital, are the target; they usually transmit continuously and are therefore easy to pick up. A Wi-Fi drone detection option can be added. The direction-finding antenna gives a direction; a position takes several sites.

The set serves detection and direction finding and does not transmit. Whether and how receiving and evaluating third-party radio signals is permitted (secrecy of telecommunications, data protection) has to be clarified for Germany and Poland before use. Detection is to be kept apart from countermeasures: jammers may be operated only by authorities in Germany and Poland (Section 91 TKG, Article 42 of the Polish Electronic Communications Law).

In selection the mast installation counts: site and height determine the line of sight, and the direction-finding antenna has to be aligned cleanly because the bearing depends on it. Semi-mobile means the set can be moved but has to be aligned anew after every move. The signature library needs upkeep; antenna cables, connectors and lightning protection should be checked regularly. The set does not see drones that do not transmit, such as autonomous or fibre-optic controlled ones; radar and cameras close that gap.