Researchers at Ulsan National Institute of Science and Technology (UNIST) have developed a sophisticated semiconductor device tailored to the challenges of a 6G world and autonomous vehicles. This inventive component not only uses minimal power but also keeps its state even when switched off. Its adaptability in variable filter circuits even allows for the precise tuning of the centre frequency band—a crucial step towards more compact and energy-efficient communication tools.
Under the guidance of Professors Myungsoo Kim and Tae-Sik Yoon, the team crafted radio-frequency (RF) switches using vanadium oxide (VOx) to boost the performance of next-generation wireless systems. Their detailed findings are published in Advanced Science.
RF switches are essential for modern communications, managing high-frequency signals in devices ranging from smartphones to autonomous systems. Thanks to its innovative design, this switch runs without standby power thanks to a memristor structure that locks in its resistance state even when the power is off, significantly cutting energy consumption.
Another standout feature is the memristor’s ability to switch resistance in mere nanoseconds, ensuring quick on/off transitions that help minimise signal processing delays. Rigorous tests have shown that the device can handle frequencies up to 67 GHz, maintaining low insertion loss and high isolation—critical for steady, high-quality communications. Simulations even indicate potential operations at frequencies reaching 4.5 THz, setting a record for oxide-based RF switches.
The research team also developed a tunable bandpass filter using the RF switch, which can shift the centre frequency by around 600 MHz. This breakthrough supports the creation of compact, multiband wireless circuits that are ideal for devices where space is at a premium.
Professor Kim Myungsoo explained, “This memristor-based RF switch shows how we can achieve compact RF front-ends that combine precise frequency control with energy efficiency. It could well form a key building block for the wireless systems of tomorrow.”
