CurtainNet - Enabling precise beamforming with a deformable antenna array on a fabric substrate

ACM Sensys'23

Recent trends in flexible antennas and printed circuit boards present an opportunity to leverage deformable substrates such as textiles to deploy large UHF, VHF and ISM band antenna arrays in smart homes. Low-frequency large antenna arrays are rarely deployed in indoor settings due to their large size which makes them bulky and difficult to deploy. By embedding these arrays on existing surfaces such as curtains, we can improve through-wall sensing, beamforming for IoT devices equipped with low-power radios and indoor localization of Bluetooth tags.

However, antenna arrays on curtains present new challenges since deformation shifts their phase centers and changes the 3D positions of antennas. We present CurtainNet, a flexible UHF-band antenna array on a large surface curtain that leverages a combination of optical and RF tracking to compensate for these changes while dealing with occlusions and phase changes. Results show that CurtainNet outperforms alternative methods by more than 155% in beamforming performance and increases indoor range by 20m.

CurtainNet Pipeline
(a) Our photo-sensing board with patch antenna. (b) Single board evaluation using Qualisys system.
A 2 x 4 array setup on store-bought curtains.
Array testing setup in a conference room.