Decoupling in a joint communication and sensing system with metasurface

Area of Science:

• Electromagnetic Engineering
• Wireless Communication Systems
• Metamaterials

Background:

• Joint Communication and Sensing (JCAS) systems integrate communication and sensing functionalities.
• Strong self-interference (SI) between transmit (TX) and receive (RX) antennas degrades performance in compact MIMO arrays.
• Existing SI cancellation methods struggle with wideband scenarios due to complexity and distortion.

Purpose of the Study:

• To present a novel metasurface-assisted decoupling structure for JCAS systems.
• To enhance electromagnetic isolation and reduce self-interference in sensing-centric full-duplex JCAS.
• To propose a hardware-algorithm co-optimization framework for improved JCAS performance.

Main Methods:

• Designed a metasurface using modified split-ring resonators (MSRRs) to suppress surface currents and reduce array coupling.
• Integrated a multi-frequency null-space projection (NSP) beamforming algorithm with the antenna array.
• Developed a 2x2 patch antenna array incorporating the metasurface for operation in the 9-10 GHz band.

Main Results:

• The metasurface effectively suppressed surface currents and reduced coupling between TX and RX arrays.
• The integrated hardware-algorithm approach significantly enhanced isolation and reduced front-end self-interference.
• Experimental characterization of the fabricated 2x2 antenna array validated the proposed decoupling approach's effectiveness.

Conclusions:

• The proposed metasurface-assisted decoupling structure offers a promising solution for mitigating self-interference in JCAS.
• Hardware-algorithm co-optimization is crucial for enhancing electromagnetic isolation in next-generation JCAS.
• This approach enables improved performance for applications like intelligent transportation and indoor wireless sensing.