Experimental demonstration of real-time optical OFDM Transmission at 7.5 Gb/s over 25-km SSMF using a 1-GHz RSOA

The 7.5-Gb/s real-time end-to-end optical orthogonal frequency-division- multiplexing (OOFDM) transceivers incorporating variable power loading on each individual subcarrier are demonstrated experimentally using a live-optimized reflective semiconductor optical amplifier intensity modulator having a modulation bandwidth as narrow as 1 GHz. Real-time OOFDM signal transmission at 7.5 Gb/s over 25-km standard single-mode fiber is achieved across the $C$-band in simple intensity modulation and direct detection systems without in-line optical amplification and dispersion compensation. © 2006 IEEE.

20 Gb/s QPSK transmission using an electro-optically modulated vertical-cavity surface-emitting laser

20 Gb/s QPSK transmission over 100 m of OM3 fibre using an EOM VCSEL under QPSK modulation is reported. Bit-error-ratio measurements are carried out to express the quality of the transmission scheme. © 2011 OSA.

Effects of constraint curvature on structural instability: tensile buckling and multiple bifurcations

Bifurcation of an elastic structure crucially depends on the curvature of the constraints against which the ends of the structure are prescribed to move, an effect which deserves more attention than it has received so far. In fact, we show theoretically and we provide definitive experimental verification that an appropriate curvature of the constraint over which the end of a structure has to slide strongly affects buckling loads and can induce: (i.) tensile buckling; (ii.) decreasing- (softening), increasing- (hardening), or constant-load (null stiffness) postcritical behaviour; (iii.) multiple bifurcations, determining for instance two bifurcation loads (one tensile and one compressive) in a single-degree-of-freedom elastic system. We show how to design a constraint profile to obtain a desired postcritical behaviour and we provide the solution for the elastica constrained to slide along a circle on one end, representing the first example of an inflexional elastica developed from a buckling in tension. These results have important practical implications in the design of compliant mechanisms and may find applications in devices operating in quasi-static or dynamic conditions.

Uncooled DWDM transmission system using tunable laser sources with anti-mode-hop control protocol

We propose an uncooled DWDM system where errors from uncontrolled laser mode-hopping are avoided by using a control protocol based on monitoring SMSR. We describe a proof-of-principle demonstration of a novel uncooled 50GHz DWDM system. © 2011 IEEE.

Multiplexed classical and quantum transmission for high bitrate quantum key distribution systems

We report the operation of a gigahertz clocked quantum key distribution system, with two classical data communication channels using coarse wavelength division multiplexing over a record fibre distance of 80km. © 2012 OSA.

Optimal constraint tightening policies for robust variable horizon model predictive control

This paper develops a technique for improving the region of attraction of a robust variable horizon model predictive controller. It considers a constrained discrete-time linear system acted upon by a bounded, but unknown time-varying state disturbance. Using constraint tightening for robustness, it is shown how the tightening policy, parameterised as direct feedback on the disturbance, can be optimised to increase the volume of an inner approximation to the controller's true region of attraction. Numerical examples demonstrate the benefits of the policy in increasing region of attraction volume and decreasing the maximum prediction horizon length. © 2012 IEEE.

Demonstration of Radio-over-Fibre Transmission of Broadband MIMO over Multimode Fibre using Mode Division Multiplexing

Abstract (40-Word Limit): A novel method for sending MIMO wireless signals to remote antenna units over a single multimode fibre is proposed. MIMO streams are sent via different fibre modes using mode division multiplexing. Combined channel measurements of 2km MMF and a typical indoor radio environment show in principle a 2x2 MIMO link at carrier frequencies up to 6GHz.