Vehicle Internet Links using Infra-Red transmission of Information (VILIRI)

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Only a third of passengers on the UK's railways seem happy with the wifi service they receive on the train. People increasingly expect free and reliable internet wherever they go and are frustrated that train journeys interrupt the entertainment and communications they value for lifestyle and work.The problem is not for lack of attention. The Government knows how much this matters to people and has called for rail franchises to include free wifi from 2020\. Although the initiative itself will guarantee no more than 1 Mbps per head, it sends a clear signal to the train operators who have so far found it difficult to justify investment in the infrastructure needed over the timeframe of the franchise contracts. Network Rail Infrastructure Limited (NRIL) is the owner and operator of most of the rail infrastructure in Great Britain and is at the forefront of attempts to find innovative solutions for this market failure.HS2 is the next major railway infrastructure project in the UK and an excellent opportunity to prove high bandwidth, reliable internet services for entire journeys. VILIRI's approach is based on Optical Wireless Communications (OWC) that uses Infra-Red (IR) frequencies to send data between train and trackside at 10Gigabits per second (10Gbps). This is more than enough for all types of internet browsing, real time communications and effectively unlimited capacity for each passenger.The innovation is to use advanced optics with high levels of concentration and carefully matched sensors that can take low power IR signals and process them reliably in real time. This needs transceivers on the train and along the track so that data is transferred by line of sight from each transceiver in turn. The quality of service achievable will support operational communications and security CCTV picture transfers, for example, as well as information and internet for the passengers.The project will enhance the capability of the optical links by advanced signal processing and multiple channels where needed. Care will be taken to ensure that the optics remain clean and clear in all weathers. Most importantly, the business case for installing the system as part of the railway infrastructure will be covered by the revenue that additional internet services will bring while passengers enjoy the basic internet service without direct charges. Capital costs will be reduced by internet connection within the provision of optical fibre that has to be laid for signalling and other functions.