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IEE Review

Issue 1 • Date Jan. 1989

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Displaying Results 1 - 5 of 5
  • Public telecoms networks. Is the UK on the right line?

    Page(s): 37 - 39
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (239 KB)  

    The introduction of digital telephone exchanges, among other factors, is causing telephone operators worldwide to set their standards for the new systems. The UK is following a slightly different path from most other countries. The main differences cover equipment specification and approval, and the installation, operation and maintenance of new equipment. British Telecom has opted for a strategy based largely on the hierarchical technique-a separate digital overlay network of 53 main switching networks interlinked by CCITT Number 7 signalling. The author discusses how this differs from the digital-island technique used in other countries. The UK regulatory situation, standards and administration practices are also discussed.<> View full abstract»

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  • Powering up-a higher system voltage for cars

    Page(s): 29 - 32
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (356 KB)  

    The author briefly describes the history of vehicle electrical system voltages. The electrical loads within a car are likely to increase in the future so a higher voltage will be necessary. The author points out that the optimum choice of voltage involves trade-offs between cost, safety, economy performance and function. The obvious choice is 24 V, which is used in commercial vehicles. The author discusses the use of this and higher voltages and whether AC or DC systems should be used.<> View full abstract»

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  • Leaders for every occasion (French engineering education)

    Page(s): 26 - 27
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (182 KB)  

    In France, graduate engineers enjoy a higher prestige and better career prospects than in most Western countries. The reasons for this lie in the educational system. The author discusses the role played by grandes ecoles-small or medium sized autonomous establishments created in response to precise needs, notably in engineering, applied science and management studies. The curriculum is briefly described. The author then discusses in more detail the way in which the students are trained for leadership.<> View full abstract»

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  • Stretching the fibre-the promise of coherent transmission

    Page(s): 19 - 22
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (281 KB)  

    Coherent transmission could transform the performance of optical systems, with jeopardising the investment in existing fibre networks. The author discusses the advantages of coherent transmission and how it was first demonstrated. The technology involved, polarisation control, and the use of frequency division multiplexing are also discussed.<> View full abstract»

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  • Pictures by telephone

    Page(s): 7 - 10
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (461 KB)  

    Normal television pictures contain far too much information to be transmitted by normal telephone systems. One way round this problem is offered by slow-scan television (SSTV). The author briefly discusses the shortcomings of fax before describing the SSTV technique. The speed of transmission and hence resolution of the picture is discussed. The applications of SSTV such as for shopping centre security are also discussed. Future developments and potential applications are mentioned.<> View full abstract»

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