Tue. Oct 20th, 2020

This new photonic chip may power 5G

The fifth generation of cellular mobile technology or 5G is expected to not just provide super high-speed data communication but also facilitate networking of people, machines and things. An array of new technological building blocks to achieve this is being developed.

An international group of scientists, including from the Indian Institute of Technology Delhi (IIT D), have developed one such key technology — a photonic chip which uses the interplay of light and sound for speedier information processing. The chip could be potentially employed in devices called phase shifters in phased-array antennas, which facilitates beaming of signals in different directions without moving.

The phased-array antennas typically have multiple antennas with elements known as phase-shifters that can steer the beams. However, as the required bandwidth and frequencies of operation rise, current electronic phase-shifters cannot keep up with the demand. The new photonic chip will be able to overcome these challenges.

“The advantage of using optics for wireless communication rather than using conventional electronics is the inherent massive bandwidth that optics deliver, low losses and immunity to electromagnetic interference,” explained Amol Choudhary from the department of electrical engineering at IIT D, and a member of the team, while speaking to India Science Wire.

“This broader area of research known as microwave photonics is getting increasingly important with the increase in the bandwidth requirement,” Choudhary added.

The study is led by researchers from the University of Sydney as well as industrial partners.

The group has developed a photonic chip that manipulates sound waves to perform phase shifting. It has been realised on silicon, which is the most common platform for microelectronics and also an important photonic material.

An optical process known as ‘stimulated Brillouin scattering, was used to create sound waves using intense light beams. This light-sound interaction creates a phase shift which is imparted to the applied electrical signal.

The researchers also used power-efficient scheme that delivers 360-degree phase shift, making such a device useful for wide applications.

Besides phased-array antennas that are critical for 5G communication, the chip can find applications in satellite communication, RADARs, sensing and medical imaging equipment. The findings have been published in journal Optica.

“This is an exciting result since we use the interaction of light and sound in a material to demonstrate results that are important for wireless communication applications, thus combining diverse areas of research to solve a real-life problem,” added Choudhary.

“Integrated silicon microwave photonics offers great potential in microwave phase shifter elements and promises compact and scalable multi-element chips that are free from electromagnetic interference,” said Satya N Gupta, communication expert and Secretary General at non-profit ITU-APT Foundation of India.

“This technology could have disruptive impact on the field of microwave photonics with the demonstration of chip-scale complex sub-systems for generating and processing radio frequency signals. Such integrated microwave photonic circuits exhibit features very attractive in the field of communications engineering such as power consumption,” Gupta added. (India Science Wire)

It can also find applications in satellite communication, RADARs, sensing and medical imaging equipment