Optical wireless

ProjectOptical Wireless

Optical Wireless

New perspectives for optical wireless communications

Evgeny Vanin

In recent years we have seen a growing international interest in research and development in optical wireless communication systems. Traditionally, the optical wireless communication technology that is often called free space optics technology relies on high power lasers for medium to long range applications. Free-space optics technology has been around for decades, but price and physical size have prevented the technology from being used for mass market deployment.

Over the last years we have seen remarkable advances in semiconductor sources such as light emitting diodes and lasers in infrared, visible and ultraviolet wavelengths, multi-array light sources and detectors, tracking and steering. These advances provide huge potentials for short to medium range optical wireless communication applications at a low power and a low cost.

Optical wireless communication technology uses completely different parts of the electromagnetic spectrum to regular radio-based wireless communications technologies. It doesn’t have the problem of limited spectrum available for data transmission and other disadvantages related to the physical properties of radio waves. Optical wireless systems may use components that are similar to those used in fibre optical systems and may provide same high data rates as fibre but without the cost associated with fibre deployment. Different from radio waves radiating in all directions and penetrating through walls, optical signals can be easily localized in spots or even focused making it nearly impossible to intercept. This feature manifests in a number of advantages. Optical wireless products do not require any license for operation worldwide. Nonintrusive optical wireless solutions can be used in locations where radio wave pollution is prohibited, e.g. in hospitals, aircrafts and industrial facilities. In majority of application scenarios using optical signals does not cause any health concerns.

Extending the reach of the fiber by using Optical Wireless LinksThe interest to optical wireless communication is empowered by quickly developing infrastructure of light sources that are intended for applications other than data communications but having attractive modulation bandwidth capabilities.  One example is the future light illumination infrastructure. The light emitting diodes that are replacing today the old-fashion light illumination bulbs are going to be available practically everywhere and be utilized for high-speed data communication. In the view of such perspectives, the future potentials of the optical wireless communications are beyond what is thinkable today.  

The Netlab of Acreo has been recently granted a project for the development of a new product in this new technological area. Acreo Netlab is a partner of the consortium that raised EUR 1.15 million from the EU Commission’s Seventh Frame Programme “Research for the benefit of SMEs” for the development of a wireless high capacity broadband product based on free-space optics. The motivation of the project originates from the fact that the number of subscribers in high capacity broadband networks is not increasing at the rate of actual fibre backbone availability. The main reason for this is that connecting fibres to houses is often cumbersome and expensive. The ConnectTOO project aims at providing a totally new opportunity to broadband service providers, and significantly increase the number of houses that will actually gain access to the high capacity broadband fibre network. The ConnectTOO consortium is coordinated by the Norwegian company Polewall – provider of a low cost point-to-point optical wireless links operating at 100Mb/s. The Acreo efforts in the project will be mainly focused on the development of a self-aligning optical subsystem for a low cost 2 Gb/s optical wireless link.

The work in the field of optical wireless communications has been started at Acreo Netlab a year while ago as a spin-off activity in a former EU project. This work resulted in the conference contribution accepted for presentation at the third workshop on Optical Wireless Communications that is one of the events at the Global Communications Conference (GLOBECOM) in Anaheim, California, USA in December this year. The conference contribution represents the work on the development of a new signal processing algorithm for advanced optical wireless communication systems. For details please refer to:

 

Evgeny Vanin, “Analytical Model for Optical Wireless OFDM System with Digital Signal Restoration”, GLOBECOM’2012, Workshop on  Optical Wireless Communications, 1-3 Dec. 2012, Anaheim, California, USA, to be published in IEEE GLOBECOM 2012 proceedings.