Hoverfly brains mapped to detect the sound of distant drones

Science Daily  March 15, 2022 Insect vision systems have been mapped for some time now to improve camera-based detections. Researchers in Australia shown that it is possible pick up clear and crisp acoustic signatures of drones, including very small and quiet ones, using an algorithm based on the hoverfly’s visual system. They converted acoustic signals into spectrograms and used the neural pathway of the hoverfly brain to improve and suppress unrelated signals and noise, increasing the detection range for the sounds they wanted to detect. They looked for narrowband and/or broadband to pick up drone acoustics at short to medium […]

Drones Use Radio Waves to Recharge Sensors While in Flight

IEEE Spectrum  April 17, 2020 An international team of researchers (Lebanon, Italy) has developed and implemented a RF energy harvesting and wake-up system that scavenges a 2.4 GHz signal from a UAV. It can deliver power wirelessly to remote sensors. The signal transmitted by the UAV is harvested and rectified to DC voltage to power a sensor on the ground. Additionally, the UAV modulates the transmitted signal to encode an address that triggers a particular sensor from sleep mode to active mode. Charging can be initiated from input power levels as low as -18.2~dBm and a sensor can be triggered […]