Development and application of optical fibre strain and pressure sensors for in-flight measurements

Fibre optic based sensors are becoming increasingly viable as replacements for traditional flight test sensors. Here we present laboratory, wind tunnel and flight test results of fibre Bragg gratings (FBG) used to measure surface strain and an extrinsic fibre Fabry–Perot interferometric (EFFPI) sensor used to measure unsteady pressure. The calibrated full scale resolution and bandwidth of the FBG and EFFPI sensors were shown to be 0.29% at 2.5 kHz up to 600 με and 0.15% at up to 10 kHz respectively up to 400 Pa. The wind tunnel tests, completed on a 30% scale model, allowed the EFFPI sensor to be developed before incorporation with the FBG system into a Bulldog aerobatic light aircraft. The aircraft was modified and certified based on Certification Standards 23 (CS-23) and flight tested with steady and dynamic manoeuvres. Aerobatic dynamic manoeuvres were performed in flight including a spin over a g-range −1g to +4g and demonstrated both the FBG and the EFFPI instruments to have sufficient resolution to analyse the wing strain and fuselage unsteady pressure characteristics. The steady manoeuvres from the EFFPI sensor matched the wind tunnel data to within experimental error while comparisons of the flight test and wind tunnel EFFPI results with a Kulite pressure sensor showed significant discrepancies between the two sets of data, greater than experimental error. This issue is discussed further in the paper

The case for "Open Access" communications infrastructure in Africa : the SAT-3/WASC cable - a briefing

This study examines the impact the SAT-3 fibre optic submarine cable has had on telecommunications in four African countries has found that the potential of the cable has not been properly exploited. Instead, ownership of the cable by telecoms incumbents in the countries researched has reinforced their market positions. The study analyses the effect ownership of the South Atlantic 3/West Africa Submarine Cable (SAT-3/WASC) has had on the communications markets in Angola, Cameroon, Ghana and Senegal. It focuses on the 'Africa section' of the submarine cable -running along the west coast of Africa down to southern Africa- with a specific emphasis on access and cost

In-sewer field-evaluation of an optical fibre-based condition monitoring system

A Fiber Bragg Grating (FBG) based monitoring system for continuous humidity and temperature measurement has been designed and evaluated experimentally in a sewer environment with high corrosion rates, humidity and the presence of gaseous hydrogen sulfide. The monitoring system has been designed specifically for field use, including packaging prepared for the harsh environment and the challenges of the operation. The system is battery powered and has hardware for controlling the interrogation equipment, power management, data logging and 4G connectivity. Results obtained show the long-term performance, over a 6-month period of non-stop monitoring of real-time data using the same probe. The data acquired was compared to the environmental data of temperature and precipitation for this period from the same location, which showed a good correlation between the expected and the measured data values. The data obtained point to the success of the optical fibre-based sensor system for monitoring in these harsh environments over long periods

Next Generation Satellite Broadband for enabling Universal Service Commitment

Peer reviewedPublisher PD

National FTTH plans in France, Italy and Portugal

In this paper, we analyze the specific national broadband plans which have been developed by some European governments to foster the deployment of next generation access networks, namely in France, Italy, and Portugal. In particular, we discuss the strategies adopted to achieve wide fibre coverage and encourage co-investment between competing operators. Finally, we highlight the similarities and differences between the strategies followed in these three countries.broadband; fibre; next generation access networks; regulation

Superfast broadband: the future is in your hands

The National Broadband Network (NBN) will deliver a comprehensive upgrade to Australia’s national broadband infrastructure. This will be of profound importance to Australia’s long-term productivity agenda. This paper, commissioned by Vodafone Australia, assesses new opportunities for the NBN. In particular, we examine how the growth of mobile services has transformed the telecommunications industry and how NBN has the potential to dramatically improve mobile telecommunications. It makes the case that the NBN, far from becoming redundant due to the explosion in mobile internet access, is in fact crucial to delivering better mobile services to both regional and urban areas without any significant increases in cost. It argues that the recent development of small mobile base stations (able to be placed on lampposts for example), connected to the NBN, can significantly increase and improve mobile coverage in both urban and regional Australia. This has the potential to radically reshape Australia’s economic and social future