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A free-space optical 64/spl times/64 fibre-to-fibre crossbar switch with spatial light modulators as the crosspoint elements is described. The design and performance of the optical and electrical components is discussed including lenses, diffraction gratings, polarising beam splitters, fibre mountings, baseplate construction, ferroelectric liquid-crystal spatial light modulators with their VLSI drive circuits and transceivers. A control system is proposed and a number of applications including avionics and computing are described. A demonstration model has been built and its performance is reported.

Adapting commercial standards to aviation provides a number of advantages over implementing specialist solutions. There has been a steady increase in the capabilities of Ethernet, particularly a 100-fold increase in available bandwidth and the introduction of extra capabilities such as Class/Quality of Service (CoS/QoS) and Virtual Local Area Networks (VLANs.) Ethernet is non-deterministic and is not error-resistant and so there have been attempts to overcome these shortcomings. BAE Systems has developed the Deterministic Ethernet-based Fault Tolerant NETwork (DEFTNET) concept. Unlike Avionics Full-Duplex Switched Ethernet (AFDX), this represents a set of techniques that require no specialised hardware or software components in the end systems. This paper summarises recent efforts to identify suitable components to demonstrate an optical, deterministic Ethernet network suitable for avionics use, including legacy, electrical, systems.

We have presented a complete GPS-over-fiber system for aircraft attitude determination. The main conclusions are that in order to a achieve a fix of phase ambiguities in a time slot of 50 s, the maximum optical attenuation of the Base path must be less than 12 dB and that in a WDM system, the maximum optical power of a baseband signal must be below -16 dBm.

Singlemode fibres will be required for airborne applications such as sensor systems, RF over fibre and wavelength division multiplexing of data. Deployment of singlemode fibres on aircraft has been slower than multimode. This is partly because of concerns over maintaining core alignment within connectors in harsh environments (vibration, shock, temperature variations etc.) but also the perceived effects of contamination given the small core size. These concerns apply to butt-coupled connectors where fibre cores are in intimate contact at a connection. Mitigation of these effects is often suggested by the use of expanded-beam technology. However, quantitative data generated using real contaminants is not freely available.

DAPHNE (Developing Aircraft PHotonic NEtworks) is a 3-year European FP7 project (started September 2009). The aim of DAPHNE is to exploit terrestrial optical networking technology (with associated performance advantages) in future aircraft and systems. The consortium comprises fifteen partners (from seven nations) ranging from major air framers (both fixed and rotary wing) through component and equipment manufacturers and leading European universities. The project is coordinated by Airbus.

Fibre optic cable is an essential component for delivering both communications and sensor information over an avionic fibre optic network. This paper discusses the performance of some potential simplex cable designs for future applications with an operating temperature of -55 to 125degC