摘要:

A large number of single mode fibre components have been developed over the last decade for telecommunication, local area network, and fibre sensor applications. They include passive components, in particular directional couplers, polarizers, polarization controllers, and filters, as well as active components, such as fibre sources and amplifiers and frequency and phase modulators. This paper presents a review of the technologies involved in these various fibre components, emphasizing in particular physical principles of operation, optical characteristics and relative performance.

DOI:10.1049/jiere.1988.0045

出版商:IERE    

年代:1988

数据来源: IET

摘要:

Over the past few years a number of advances have been made towards the development of a new type of optical sensor based on the activation and detection by optical means of resonant vibrations in simple mechanical devices. This paper describes three strands of technology—resonator sensing, optical fibre systems and silicon micromachining—the judicious interweaving of which underlies the most promising of these advances; it then presents a review of the published work to date and ends with a personal view of possible future developments.

DOI:10.1049/jiere.1988.0044

出版商:IERE    

年代:1988

数据来源: IET

摘要:

Hybrid optical sensors which use conventional sensing methods to give an optical output combine the benefits of established measurement methods with the advantages of optical fibre transmission and may incorporate intelligence. Non-resonant and resonant systems are reviewed; resonant systems give a stable digital output which can be corruption free. The potential of non-hybrid resonant optical sensors is evaluated.

DOI:10.1049/jiere.1988.0043

出版商:IERE    

年代:1988

数据来源: IET

摘要:

A fibre-optic frequency shifter based on the use of flexure waves to produce a travelling perturbation which couples the polarization modes of birefringent optical fibre is described. In experiments, frequency shifts of about 790 kHz were produced. A dispersion relation for the flexure waves in the fibre has been derived and was shown to be valid in experiments. The device is described using coupled mode theory, and it is shown that optimum mode coupling will occur when the wavelength of the flexure waves is twice the birefringent beat length of the fibre.

DOI:10.1049/jiere.1988.0042

出版商:IERE    

年代:1988

数据来源: IET

摘要:

The unique advantages afforded in a number of application areas by the use of distributed fibre-optic sensor (DFOS) systems have been recognized by many researchers. Approaches described to date can be categorized as being either ‘intrinsic-distributed’ or ‘quasi-distributed’. In the case of intrinsic-distributed sensing, a single length of fibre forms an extended sensor element which senses the measurand field continuously over its entire length, whereas quasi-distributed sensing approaches utilize discrete fibre or non-fibre sensor elements typically arranged in a linear array. More geometrically versatile sensor network topologies can also be formed by multiplexing several discrete ‘point’ sensors with common input/output fibres. This paper reviews this broad and rapidly expanding area of distributed and multiplexed optical fibre sensor technology.

DOI:10.1049/jiere.1988.0041

出版商:IERE    

年代:1988

数据来源: IET

摘要:

An analysis of fully-distributed optical-fibre sensor (DOFS) systems, with particular reference to the measurement of pressure, strain and temperature in industrial environments, is presented. The analysis seeks to establish relationships between primary system parameters such as sensitivity, accuracy, bandwidth, resolution and dynamic range. These relationships allow appropriate trade-offs to be made in order to meet any given set of industrial requirements, and also allow quantitative comparisons to be made amongst the various kinds of DOFS systems.The physical phenomena which may be used in DOFS are considered, leading to the conclusion that, to give a performance likely to be generally attractive for industrial application, systems which use optical phase modulation by the measurand should be used.The present state-of-the-art with regard to component technology in support of DOFS is reviewed, with the conclusion that most of the requirements can be met already, and that present trends should soon take care of the remainder.

DOI:10.1049/jiere.1988.0048

出版商:IERE    

年代:1988

数据来源: IET

摘要:

The transition from analogue coaxial cable to digital optical fibre submarine systems has required a new technology to be established and complementary technologies to be developed for the design, evaluation and operational support of these new systems. The common design parameter throughout is reliability; not only must the overall system design satisfy the reliability objective but the component parts must be shown to exhibit the necessary low level of failure for this to be achieved.1988 sees the commissioning of TAT-8, the first trans atlantic optical fibre submarine cable system. In addition a number of submarine cable systems linking the UK mainland with other British Islands and Europe will be made available. This paper reviews the current generation of submarine cable systems based on 1.3μm and emerging 1.55μm technologies and discusses the opportunities offered to planners and network operators from developments in networking, optical repeaters and non-silica fibres.

DOI:10.1049/jiere.1988.0047

出版商:IERE    

年代:1988

数据来源: IET