Photonics-based wireless link boosts data transmission
Wireless communication is an essential part of modern life, with researchers across the world working on the next evolution of communication networks, called “beyond 5G” or 6G networks. To enable the near-instantaneous communication needed for applications like augmented reality or the remote control of surgical robots, ultra-high data speeds will be needed on wireless channels. Researchers from Osaka University and IMRA AMERICA have developed a way to increase these data speeds by reducing the noise in the system through lasers.
To pack in large amounts of data while keeping responses fast, the sub-terahertz band, which extends from 100 GHz, will be used by 6G transmitters and receivers. An innovative approach called “multi-level signal modulation” is used to increase the data transmission rate of these wireless links. However, when operating at the top end of these high frequencies, multi-level signal modulation becomes highly sensitive to noise. To work well, it requires precise reference signals, and when those signals begin to shift forward and backward in time (known as “phase noise”), the performance of multi-level signal modulation drops.
Lead researcher Keisuke Maekawa said the problem has limited 300 GHz communications. “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,” Maekawa said.
The researchers used a stimulated Brillouin scattering laser, which uses interactions between sound and light waves to generate a precise signal. They then set up a 300 GHz-band wireless communication system that uses the laser-based signal generator in the transmitter and receiver. The system also used online digital signal processing (DSP) to demodulate the signals in the receiver and increase the data rate.
“Our team achieved a single-channel transmission rate of 240 gigabits per second,” Tadao Nagatsuma, PI of the project, said.
The researchers believe that with multiplexing techniques (where more than one channel can be used) and more sensitive receivers, the data rate can be increased to 1 terabit per second, bringing in a new era of near-instantaneous global communication.
Using quantum dots for solid-state optical cooling
Researchers have investigated a cooling phenomenon in a halide perovskite-based...
Zero-gravity tech could enable circuit repairs in space
Researchers have developed a special ink and 3D printer that can function in zero gravity.
Electron microscopy reveals colours of outermost electron layer
Researchers have used atomic-resolution secondary electron (SE) imaging to capture the atomic...
