Dynamic Tuning of Notch Bands in UWB Antenna Based on Liquid Metal for Cognitive Radio Applications

This communication introduces an innovative approach to achieving an ultrawideband (UWB) reconfigurable multinotch band antenna. The antenna's performance is dynamically tuned using a variable liquid metal (LM) coupling length, making it suitable for applications in cognitive radio systems. The tuning mechanism involves controlling the LM within 3-D-printed microfluidic channels through the application of variable dc voltage. The proposed mechanism generates four distinct notch bands without any overlap. With a straightforward configuration and compact size, the proposed antenna spans the UWB spectrum [(4.1 to 12.5) GHz] while effectively generating band rejection in various application frequency bands, including WiMAX, WiFi, and WLAN, which is valuable for minimizing interference from these commonly used communication standards. The prototype measurements closely align with simulations, validating the feasibility and practical advantages of this liquid metal-based reconfigurable antenna design for cognitive radio systems.