Fully Wireless Collaborative Beamforming Using A Three-Element Coherent Distributed Phased Array

In this work we experimentally demonstrate a wirelessly coordinated three-element coherent distributed phased array performing beamforming and beam steering to a target in the far-field over 17 m at a carrier frequency of 1.05 GHz. We build on our previous work utilizing a high accuracy two-way time transfer (TWTT) technique for inter-node time synchronization and ranging and an analog continuous two-tone frequency transfer technique to perform syntonization by moving to a fully wireless architecture, without the need for external reference signals such as global navigation satellite system (GNSS)-derived pulse-per-second (PPS), including a distributed computing system architecture, and the use of fully wireless communication links between nodes. Finally, we perform a far-field beamforming experiment with beam steering to a receiver 17 m away at a carrier frequency of 1.05 GHz and demonstrate a beamforming coherent gain of 0.95 (9.32 dB) with a beamforming inter-element timing accuracy of below 60 ps.