Low power, nonvolatile RF switch promises energy efficient 6G and autonomous vehicle communication

The research team at UNIST has launched new semiconductor devices optimized for next-generation 6G ERA and autonomous operation, offering low power consumption and non-volatile operation. This innovative device can also integrate into a variable filter circuit that can adjust the central frequency band, paving the way for more compact and energy-efficient communications equipment.

Co-led by Professor Myungsoo of the Faculty of Electrical Engineering and Professor Tae-Sik Yoon of the Faculty of Semiconductor Materials and Devices Engineering at UNIST, the team announced the development of a nonvolatile radio frequency (RF) switch based on vanadium oxide (VOX) for next-generation wireless communication systems. This paper is published in Advanced Science.

RF switches are essential semiconductor components for modern wireless communication systems such as autonomous systems, smartphones, VR, and AR. Controls the flow of high-frequency signals within the circuit by connecting or disconnecting specific routes and enabling reliable signal routing.

The newly developed RF switch operates without standby power and works effectively in high frequency bands suitable for high-speed, large-capacity communications. This is possible through its memorist structure. This is a device that can maintain a resistance state even when the power supply is turned off due to its non-volatile characteristics.

This characteristic allows the switch to remain set without consuming standby power, significantly reducing energy consumption. Additionally, Memristor’s resistive switching speeds are in order of several nanoseconds, allowing for quick on/off switching and minimizing signal processing delays.

Experimental testing demonstrates that the device can process high-frequency signals to 67 GHz, maintain low insertion loss (less than 0.46 dB) in the ON state and high separation (over 20 dB) in the off state. Reduced insertion loss and higher separation directly correspond to improved communication quality.

The simulations further show that the device can operate at frequencies up to 4.5 THz, representing the highest cutoff frequency reported between oxide-based RF switches to date.

The researchers also developed an adjustable bandpass filter using the RF switch. This electronic circuit allows the center frequency to be adjusted within the range of approximately 600 MHz. Such multiband filters simplify circuit design, reduce size and are very suitable for highly integrated wireless communication devices.

Professor Kim Mung-gu said, “Memoryster-based RF switches demonstrate the potential to realize a compact RF front-end that combines frequency selectivity and energy efficiency. This development could serve as a fundamental component of next-generation wireless communication systems.”