“This new microwave filter chip has the potential to improve wireless communication, such as 6G, leading to faster internet connections, better overall communication experiences and lower costs and energy consumption for wireless communication systems,” says researcher Xingjun Wang from Peking University in a media release. This chip has the potential to bring about significant advancements in communication technology that could directly and indirectly impact people's lives by enabling new experiences and increasing the efficiency and effectiveness of communication systems, he adds.
The researchers have detailed in Photonics Research how their innovative photonic filter surpasses current electronic device restrictions by performing multiple tasks while being the size of a computer chip and utilizing less power than standard filters. Additionally, the team has shown that this photonic filter operates efficiently across an extensive radio frequency spectrum that exceeds 30 GHz, thereby enabling it to support forthcoming 6G technology.
Wang predicts that with the relentless expansion of the electro-optic bandwidth in optoelectronic devices, the integrated microwave photonics filter will undeniably emerge as a crucial remedy for upcoming 6G wireless communications. He emphasizes that only a meticulously crafted integrated microwave photonics link can deliver outstanding filtering performance while keeping costs and power consumption low.
How does the filter work?
The ongoing development of 6G technology aims to enhance the performance of the already deployed 5G communication networks. By employing the millimeter wave and terahertz frequency bands, 6G networks are poised to transmit greater amounts of data at faster speeds. However, the utilization of an expansive frequency spectrum and increased data rates could potentially result in interference among various communication channels.
To solve this issue, the research team has been striving to create a filter that safeguards signal receivers from diverse types of interference spanning the entire radio frequency spectrum. In order to make it suitable for extensive deployment, it should be compact, energy-efficient, possess multiple filtering capabilities, and be incorporated on a chip while also being cost-effective. Nevertheless, earlier efforts have been constrained by limited functions, bulky size, narrow bandwidth, or the necessity of specific electrical components.
The team says that their novel filter boasts compact size, affordability, low power consumption, and the ability to perform various filtering functions. This makes it possible for the filter to be seamlessly integrated into a computer chip. The filter is composed of four primary components:
Phase modulator – takes in the radio frequency signal and embeds it onto the optical domain
Double-ring – functions as a modulator format shape
Adjustable micro-ring – serves as the central component for signal processing
Photodetector – retrieves the radio frequency signal from the optical signal and acts as its output
According to Wang, the most significant breakthrough lies in overcoming device limitations and facilitating seamless collaboration between them. By leveraging the combined power of double-ring and microring technology, they have developed a single-stage-adjustable cascaded-microring architecture that maintains consistent intensity levels, known as ICSSA-CM. This architecture boasts impressive reconfigurability, eliminating the need for additional radio frequency devices and streamlining the overall system composition, making it easier to construct various filtering functions.
Displaying proficiency
To evaluate the device, the scientists used high-frequency probes to introduce a radio frequency signal into the chip and captured the resultant signal using a high-speed photodetector. To mimic the production of 2Gb/s high-speed wireless transmission signals, they utilized an arbitrary waveform generator, directional antennas, and a high-speed oscilloscope to capture the processed signal. The researchers demonstrated the filter's effectiveness by contrasting the outcomes with and without the filter.
The study authors compared the results obtained with and without the filter to evaluate the efficacy of the new device. Overall, the findings indicate that the simplified photonic structure delivers similar results to previous programmable integrated microwave photonic filters comprising multiple repeating units, but with lower loss and system complexity. This enhances its durability, energy efficiency, and manufacturing convenience compared to previous devices.
The team’s next objective is to boost the modulator's efficiency and optimize the filter architecture, resulting in a high dynamic range, low noise, and seamless integration across both device and system levels.
See Also: 5G: How It Works and Why It Isn’t All That Scary
Faster and more reliable internet connections could improve productivity and facilitate remote work, while lower energy consumption could help reduce carbon emissions and combat climate change. Additionally, advancements in wireless communication technology could pave the way for new innovations in mobility and smart home technology, allowing for more efficient and personalized experiences. Overall, this new microwave filter chip represents a major step forward in the development of wireless communication technology and has the potential to significantly enhance the quality of life for people around the world.
