This operation is made possible by a programmable photonic processor built on a 5mm2 silicon IC.
The processor is able to receive all the optical beams through a multitude of microscopic optical antennas integrated on the chip, to manipulate them through a network of integrated interferometers and to separate them on distinct optical fibres, eliminating mutual interference.
This device allows information quantities of over 5000 Ghz to be managed, at least 100 times greater than current high-capacity wireless systems.
Similarly to what happens in optical fibres, even in free space light can travel in the form of beams having different shapes, called “modes”, and each of these modes can carry a flow of information.
Generating, manipulating and receiving more modes therefore means transmitting more information. The problem is that free space is a much more hostile, variable and unpredictable environment for light than an optical fibre.
Obstacles, atmospheric agents or more simply the wind encountered along the way, can alter the shape of the light beams, mix them and make them at first sight unrecognisable and unusable.
“A peculiarity of our photonic processor is that it can self-configure very simply, without the need for complex control techniques. This allows scalability to new versions of the device, capable of handling many beams at the same time, further increasing the transmission capacity. It is also able to adapt in real time to compensate for effects introduced by moving obstacles or atmospheric turbulence, allowing the establishment and maintenance of optimal optical connections”, says Francesco Morichetti, head of the Photonic Devices Lab at the Politecnico di Milano.
“There are many applications in other areas that require advanced processing of optical beams, including high-precision positioning and localization systems for self-driving vehicles, sensors and remote object recognition, portable and wearable devices for augmented reality and new investigation
Communicating anytime, anywhere, with anyone and anything has become an essential necessity of our society and of our very existence. In order to exchange information in any situation, while in the car, doing sports or in remote areas of the planet, the most natural and flexible way is to use devices that communicate without cables through free space, wireless. As with cable transmissions, in which an epochal technological leap took place with the advent of optical fibres, for wireless communications too, it is expected that optical connections will soon represent the new frontier.
The activity is funded by the European Horizon2020 Superpixels project which aims to create next-generation sensor and imaging systems by exploiting the on-chip manipulation of light signals