New breakthroughs in optical wireless technology use photonic chips that effectively shape light to improve data transmission. This is crucial to future advances in wireless networks and high-speed data processing. Fiber optic wireless may no longer have any obstacles.A study conducted by the Polytechnic University of Milan in collaboration with the Sant'Anna School of Pisa, the University of Glasgow and Stanford University, and published in the prestigious journal Nature Photonics, makes it possible to create a photonic chip that can mathematically calculate the optimal shape that light can best pass through any environment, even unknown or time-varying ones.
One problem is well known: light is sensitive to any form of obstruction, even very small ones. For example, think about how we see objects when looking through a frosted window or when our glasses are fogged up. The effect is very similar to the beams of light carrying data streams in optical wireless systems: the information is still there, but it's completely distorted and extremely difficult to retrieve.
The devices developed in this study are small silicon chips that act as smart transceivers: working in pairs, they can automatically and independently "calculate" what shape a beam needs to be in order to pass through a common environment with maximum efficiency. That's not all: they can also generate multiple overlapping beams, each with its own shape, and guide them without interfering with each other; in this way, the transmission capacity is greatly increased, as will be required for next-generation wireless systems.
"Our chips are mathematical processors that can perform calculations with light very quickly and efficiently, consuming almost no energy. The light beams are generated by simple algebraic operations (essentially summations and multiplications), performed directly on the light signals and transmitted through micro-antennas integrated directly on the chip. This technology has many advantages: extremely simple processing, high energy efficiency and a huge bandwidth of more than 5000 GHz." explains Francesco Morichetti, head of the Photonic Devices Laboratory at Politecnico di Milano.
"Today, all information is digital, but in fact, images, sounds and all data are essentially analog. Digitalization does allow for very complex processing, but as the amount of data increases, these operations become increasingly unsustainable in terms of energy and computing. Today, there is a growing interest in the use of specialized circuits (Analog coprocessors) There is great interest in returning to analog technology, and dedicated circuits will be the enablers of future 5G and 6G wireless interconnection systems. This is how our chips work," said Andrea Melloni, director of Polifab, the Center for Micro and Nanotechnology at Politecnico di Milano.
"Analog computing using optical processors is crucial in many application scenarios, including mathematical accelerators for neuromorphic systems, high-performance computing (HPC) and artificial intelligence, quantum computers and cryptography, advanced localization, localization and sensor systems and, in general, systems that need to process large amounts of data at very high speeds," adds Marc Sorel, professor of electronics at the TeCIP Institute (Institute of Telecommunications, Computer Engineering and Photonics) of the High School of Santa Ana.