A team of researchers from Osaka University, Japan, and IMRA America has set new records by utilizing laser technology to significantly enhance data transmission speeds, according to a recent study published in IEICE Electronics Express.
The key lies in the reduction of system noise, a remarkable accomplishment attained through the application of photonics in a sub-terahertz band spanning from 100 GHz to 300 GHz. The innovative approach contributes to the enhanced efficiency and performance of the system.
“Our team achieved a single-channel transmission rate of 240 gigabits per second. This is the highest transmission rate obtained so far in the world using online DSP,” PI of the project, Tadao Nagatsuma said.
To accommodate substantial data loads and maintain swift response times, 6G transmitters and receivers will leverage the sub-terahertz band, spanning from 100 GHz to 300 GHz. Employing an advanced technique known as “multi-level signal modulation,” these wireless links undergo a sophisticated process to further augment the data transmission rate.
‘Noise Sensitivity’
At the upper echelons of extremely high frequencies, the effectiveness of multi-level signal modulation becomes intricately sensitive to noise. Its optimal functionality depends on precise reference signals, and when these signals experience fluctuations in timing, known as “phase noise,” the performance of multi-level signal modulation diminishes.
“This problem has limited 300-GHz communications so far. However, we found that at high frequencies, a signal generator based on a photonic device had much less phase noise than a conventional electrical signal generator,” lead author of the study, Keisuke Maekawa explained.
The research team used the capabilities of a stimulated Brillouin scattering laser, leveraging the intricate interplay between sound and light waves to generate a precise signal. Subsequently, they established a wireless communication system operating in the 300 GHz band, incorporating the laser-based signal generator in both the transmitter and receiver components.
Additionally, the system implemented online digital signal processing (DSP) in the receiver, effectively demodulating signals and substantially boosting the overall data rate.
Researchers around the globe are currently immersed in pioneering efforts to shape the future of communication networks by developing the next generation beyond 5G, commonly referred to as 6G networks, to facilitate near-instantaneous communication, catering to the demands of cutting-edge applications such as augmented reality and remote control of surgical robots.
To realize this vision, it becomes imperative to harness ultra-high data speeds on wireless channels, laying the foundation for seamless connectivity and transformative user experiences.
The outcomes of the study represent a noteworthy stride in advancing 300 GHz-band wireless communication. The researchers envision that through the incorporation of advanced multiplexing techniques, enabling the concurrent use of multiple channels, and augmenting receiver sensitivity, they can push the data rate to an astonishing 1 terabit per second. This breakthrough promises to usher in a transformative era of nearly instantaneous global communication.
