Development and Flight Tests of Wing-Mounted T/R Modules for a UAS-borne Multichannel VHF Ice Penetrating Radar

We developed a set of compact transmit/receive (T/R) modules as a part of a multi-channel ice penetrating radar system for operation onboard an ultra-long endurance unmanned aerial system (UAS). Notably, the design, construction and laboratory testing of the circuitry involved several undergraduate and first-term graduate students. The modules operate in the 60–80 MHz band and include a pulsed driver and high-power amplifier capable of ~200-W peak output with up to 10% duty cycle; a fast T/R switch; a low-noise amplifier; and DC-bias circuitry to operate from a single 28 VDC power source. Each module weighs ~0.6 kg and consumes a maximum of ~43 WDC, which made it possible to integrate them next to the antenna elements to minimize feed cable losses. In this paper, we present an overview of the T/R module design, construction and laboratory tests. We briefly discuss the integration of the modules onto a Vanilla UAS and show initial results from a flight test conducted over water in the continental US to verify functionality.