Wavelength agnostic WDM strategies for avionic telecommunications

This thesis investigates the possibility of deploying a fibre optic network on aircraft; the network should provide 1.25 Gbps links between various end nodes throughout the aircraft. Particular attention has been paid to Wavelength Division Multiplexing (WDM) in Passive Optical Networks (PONs) and how the network is affected by the harsh environment found on aircraft. The harsh environment presents a particular challenge with respect to the operational temperature range. Over this range it is desirable to minimise any additional weight and power consumption associated with cooling network components. One technique assessed to implement WDM with minimised cooling is to use spectrum slicing to seed reflective semiconductor optical amplifiers which will be positioned at each end node. In theory these 'colourless' nodes will be temperature insensitive and capable of uncooled operation. This has been thoroughly studied and temperature ranges for uncooled operation identified with different end node components. Different cooling techniques have also been studied; one technique using a phase change material for passive cooling with no direct power consumption and the other using a thermo-electric cooler. The efficiencies of these techniques have been compared by analysing their impact on fuel burn. The use of distributed feedback lasers in a WDM PON has also been investigated and a novel method for reducing power consumption has been proposed. It has been predicted that this could reduce the power consumption of the optical transmitters in a realistic avionic environment by up to 20 %. This network has been compared to the network using the spectrum slicing technique with particular attention paid to the relative power consumptions. The merits of both networks in the avionic context have been discussed and different scenarios where each network is suitable have been identified.This thesis investigates the possibility of deploying a fibre optic network on aircraft; the network should provide 1.25 Gbps links between various end nodes throughout the aircraft. Particular attention has been paid to Wavelength Division Multiplexing (WDM) in Passive Optical Networks (PONs) and how the network is affected by the harsh environment found on aircraft. The harsh environment presents a particular challenge with respect to the operational temperature range. Over this range it is desirable to minimise any additional weight and power consumption associated with cooling network components. One technique assessed to implement WDM with minimised cooling is to use spectrum slicing to seed reflective semiconductor optical amplifiers which will be positioned at each end node. In theory these 'colourless' nodes will be temperature insensitive and capable of uncooled operation. This has been thoroughly studied and temperature ranges for uncooled operation identified with different end node components. Different cooling techniques have also been studied; one technique using a phase change material for passive cooling with no direct power consumption and the other using a thermo-electric cooler. The efficiencies of these techniques have been compared by analysing their impact on fuel burn. The use of distributed feedback lasers in a WDM PON has also been investigated and a novel method for reducing power consumption has been proposed. It has been predicted that this could reduce the power consumption of the optical transmitters in a realistic avionic environment by up to 20 %. This network has been compared to the network using the spectrum slicing technique with particular attention paid to the relative power consumptions. The merits of both networks in the avionic context have been discussed and different scenarios where each network is suitable have been identified