DOI:10.1049/ree.1984.0065

出版商:IERE    

年代:1984

数据来源: IET

摘要:

The paper deals with the design principles of a type of microprocessor-based receiver for the Decca Navigator continuous-wave, hyperbolic radio-navigation system. Two experimental receivers are described, one for automatic vehicle location, the other hand-portable. Both are fully automatic in operation. Novel features of their hardware software are outlined and the results of land-vehicle, marine, airborne and hand-held field trials are presented. The results demonstrate that, although the receivers are small, light, cheap to manufacture and low in power consumption, their accuracy, fix repeatability and skywave interference sensitivity compare favourably with those of traditional analogue receivers.

DOI:10.1049/ree.1984.0066

出版商:IERE    

年代:1984

数据来源: IET

摘要:

Over the past decade or so, travelling-wave-tube amplifiers for communications have advanced from field replaceable glass bodies to packaged metal ceramic tube construction and from large, fully adjustable, linear power supplies to miniature, highly efficient, preset switched mode units. The principal features of modern tube design are based on metal ceramic technology, dispenser cathodes, two-stage depressed collectors and samarium cobalt magnets.Equally important, though often neglected in the literature, is the design and construction of the power supply and in particular the interface between tube and supply. These problems and their solutions in development and manufacture are discussed in this paper and a case is presented for a more integrated design approach.

DOI:10.1049/ree.1984.0067

出版商:IERE    

年代:1984

数据来源: IET

摘要:

The paper describes the introduction of a factory information system employing manufacturing resource planning in a plant making machine tools. Details are given of some of the initial results.

DOI:10.1049/ree.1984.0068

出版商:IERE    

年代:1984

数据来源: IET

摘要:

The GEC Hirst Research Centre was formally opened just over 60 years ago. This paper reviews the origins of the Laboratories, records their early history, and describes some of the technical work which they have undertaken. Although the Laboratories were set up to serve all the diverse activities of GEC, the present paper concentrates on electronics and communications.

DOI:10.1049/ree.1984.0069

出版商:IERE    

年代:1984

数据来源: IET

摘要:

A recent paper1has described the design and performance of a waveguide-fed parallel plate lens which provides five beams from a sixteen element antenna array, with sidelobes ≈ − 20 dB and beam crossovers ≈ − 10dB, in the frequency band 8–12 GHz. A microstrip version of this lens has been designed, constructed and tested, with the addition of a beam port overlap network to now provide nine beams with crossovers ≈ − 2 dB. Fair performance is achieved at midband, but internal reflections are found to limit the bandwidth of the microstrip lens design.

DOI:10.1049/ree.1984.0070

出版商:IERE    

年代:1984

数据来源: IET

摘要:

Radio waves can induce currents in electrical firing circuits used for blasting in quarries, and for similar industrial purposes, and could cause premature detonation if sufficiently strong. The paper describes an experimental and theoretical study of the currents in typical circuits, and a set of maximum-current curves is presented. These curves form the basis of a set of safe field-strength curves contained in the British Standard guide to the prevention of inadvertent initiation of electro-explosive devices by radio-frequency radiation.

DOI:10.1049/ree.1984.0071

出版商:IERE    

年代:1984

数据来源: IET

摘要:

The paper describes a technique for implementing moving target indication (m.t.i.) in an independent bistatic radar receiver. Conventional techniques for m.t.i., and the particular features and advantages of the bistatic radar configuration are also reviewed.The technique of phase priming by clutter echoes is suggested as a means for providing a coherent reference at the receiver, without need for any link between radar transmitter and receiver. An oscillator at the receiver is primed at the instant of switch-on at the beginning of each p.r.i. with a small sample of echo signal from close-in stable clutter, such that its phase is determined by that of the clutter echo. This enables m.t.i. processing to be obtained, just as with a conventional monostatic radar system.An experimental system using this principle is described, and results demonstrated and discussed.

DOI:10.1049/ree.1984.0072

出版商:IERE    

年代:1984

数据来源: IET