Unmanned aerial vehicles (UAVs) — often referred to as drones – ranging from small, low-cost consumer products to extremely advanced and costly versions, are proliferating at a high rate. Among the many and varied estimates of the market from various researchers and forecasters are “USD 552 million in 2014 and is expected to grow at a CAGR of 16.9%“; “World Drone Market Seen Nearing $127 Billion in 2020“; and “Drones Market worth 21.23 Billion USD by 2022“; many other estimates and predictions are available. Regardless of which one you look at, the bottom line is the same: it’s an area of intense activity, with major military, commercial (especially agriculture) and personal-use implications. Amazon recently tested using a drone for package delivery (mostly a clever publicity stunt, IMO) which received lots of attention (see here) from the always-looking-for-trend media.
Of course, this drone proliferation brings new concerns, especially on the military side: what about low-cost drones spying on troops, or even carrying explosives? Worse, what about a swarm of such drones? How do you see that coming, protect yourself against them, and react?
The answer to that first question is not easy. The intuitive, reflexive answer might be to consider a small conventional radar system, but there are severe problems: you need fast, 3-D 360o coverage; the drones are fairly small with correspondingly small radar cross sections (yes, powerful and sensitive radar could see the, but such systems are a challenge to field); and drones can fly close the ground and under trees and similar cover, so their visibility to radar is easily obscured from a ground-based as well as airborne radar.
That's why other solutions are needed. One very interesting system I recently read about is from Aaronia AG, Strickscheid, Germany . Their IsoLOG 3D System intercepts and analyses the RF emitted by the drone's onboard systems, Figure 1 , and also implements pattern recognition on signals from the drone operator's control unit. They claim a detection range of 1 km, as the press release explains along with other key points.
The basic Aaronia Drone Detector configuration, here set up for mobile operation, combines a single antenna with their XFR V5 PRO portable unit.
Key to the system's performance is sophisticated signal processing and analysis, of course, but it all starts at the analog/RF front end, as these things usually do. Here, the signal path begins with the Aaronia IsoLOG 3D Tracking Array Antenna, a PoE-connected, electronically scanned 9 kHz-to-40 GHz unit with hemispherical coverage and no moving parts, Figure 2 .