In this paper, triangular lattice index-guiding photonic crystal fibres (PCFs) are synthesized to compensate the chromatic dispersion of a single mode fibre (SMF-28) for an 80 km optical link operating at 1.55 μm, by using a directed tabu search algorithm. Hole-to-hole distance, circular air-hole diameter, solid-core diameter, ring number and PCF length parameters are optimized for this purpose. Three synthesized PCFs with different physical parameters are compared in terms of their objective functions values, residual dispersions, compensation ratios and confinement losses.

This article proposes and examines a solution in which the base-station for the fifth generation radio access network is simplified by using a single millimeter-wave oscillator in the central-station and distributing its millimeter-wave signal to the base-stations. The system is designed in such a way that the low-phase-noise signal generated by an opto-electronic oscillator is transmitted from the central-station to multiple base-stations via a passive optical network infrastructure. A novel flexible approach with a single-loop opto-electronic oscillator at the transmitting end and a tunable dispersion-compensation module at the receiving end(s) is proposed to distribute a power-penalty-free millimeter-wave signal in the radio access network. Power-penalty-free signal transmission from 10 MHz up to 45 GHz with an optical length of 20 km is achieved by a combination of a tunable dispersion-compensation module and an optical delay line. In addition, measurements with a fixed modulation frequency of 39 GHz and discretely incrementing optical fiber lengths from 0.625 km to 20 km are shown. Finally, a preliminary idea for an automatically controlled feedback-loop tuning system is proposed as a further research entry point.

A 100 km long dense wavelength division multiplexed optical network design with a capacity of 1.28 Tbps is proposed in this paper. The novelty of this work is the use of a dispersion compensating fibre as a Raman amplifier in the S-band for a high-capacity dense wavelength division multiplexing network. The transmission is accomplished auspiciously in the wavelength range from 196 THz to 202. 35THz. The coupling of a Raman amplifier made the realisation of the S-band possible in the network, as the erbium-doped fibre amplifier is competent for amplification in C- and L-bands only. Further, a pump coupler is used for multiple pumping to enlarge the gain spectrum for a high-capacity optical network. The performance analysis of the network is carried out systematically in terms of bit error rate (BER), eye diagram, Q-factor, and optical signal to noise ratio (OSNR). The results demonstrate that the proposed set-up shows adequately low BER, sufficient Q-factor values, wide eye-opening, and commendable OSNR for all receiving channels.