Adaptive Beamforming is a signal processing technique that steers sensor or antenna arrays toward desired signals while minimizing interference. NEC Labs America applies Adaptive Beamforming in distributed acoustic sensing, radar, and optical fiber arrays. The method improves sensitivity and accuracy by dynamically adjusting in real time, making it useful for infrastructure monitoring, seismic detection, and communications in noisy environments.

Posts

Advances in Fiber Sensing

In this talk, we will present recent technological advances in fiber sensing applications with long monitoring distances orextending multiple fiber spans. In forward-transmission-based sensing, adaptive beamforming techniques weredemonstrated to achieve multi-event vibration sensing in environments with interference and jamming with significantimprovements in signal reconstruction, noise reduction, and interference rejection from other locations. For sensing oversubmarine cables with many fiber spans with repeaters, it is shown that distributed reflection from Rayleigh scattering canbe detected with sufficient SNR for fiber sensing using HLLB paths. In particular, longitudinal averaging of receivedRayleigh scattered signals can facilitate state-of-polarization-based, multi-span sensing using eigenvalue method.

Multi-Event Distributed Forwarding Sensing with Dual-Sensor Adaptive Beamforming

We present adaptive beamforming techniques to forward-transmission multi-event vibration sensing in environments with interference and jamming. Experimental validation over 100km fiber demonstrates significant improvements on signal reconstruction, noise reduction, and interference rejection from other locations.