RF inhibitors: the challenges and trends in disrupting adversary UAS systems Defence and security forces are seeing a prevalence of malicious UAS capable of delivering harmful payloads or disrupting ground and aerial operations in conflict-zones and critical national infrastructure sites. ECS has consistently outperformed its competitors in developing RF inhibitor-based countermeasures that address sophisticated frequency-hopping drones by generating complex defeat waveform generation. The main challenge facing RF inhibitor systems today is spectral cleanliness; RF spectrum congestion is rife in a world where most assets communicate. Wanting to inhibit or disrupt a particular data link while not affecting critical internal communication requires spectral cleanliness and a very focused RF attack. The ECS SDR Claw solution allows for exactly that. Claw offers a smarter system that allows friendly communications to remain in operation within the RF spectrum, while denying the use of the spectrum to adversaries. The Claw directional inhibitor is a self-contained system that combines the RF power electronics with a high-gain multi-band directional antenna system. An ongoing trend in RF inhibitors will be developing them to execute an even more focused attack, with the ability to concentrate all energy in the right direction and only in the frequency areas where the UAV threat has been established. As threats get more sophisticated, the drive is to continue to improve protection with new technology in this space.