# Electrical Engineers, Proceedings of the Institution of

## Filter Results

Displaying Results 1 - 25 of 43
• ### Evaluation of beam-scanning dual-reflector antennas

Publication Year: 1977, Page(s):1111 - 1113
Cited by:  Papers (3)
| | PDF (268 KB)

The gain/scan characteristics of four different types of dual-reflector antenna are compared. The theoretical analysis is based on the receive mode of operation in which geometrical optics, geometrical theory of diffraction and physical-optics technique are applied. Measured results of one of the designed antenna are found to agree well with prediction. View full abstract»

• ### Some resonance effects in scattering of microwaves by hydrometeors

Publication Year: 1977, Page(s):1114 - 1116
Cited by:  Papers (1)
| | PDF (327 KB)

Investigation of the polarisation properties of scattered electromagnetic waves from spheroidal raindrops in the microwave region has resulted in the discovery of a resonance effect at 6 GHz. The behaviour of the scattering amplitudes and crosspolarisation of several drop sizes are shown. It is further shown that such effects occur at millimetre wave frequencies for ice particles, an example being... View full abstract»

• ### Computer-program description. Computer-program system for evaluating partial and total antenna directivities from measured data. Computer-program description

Publication Year: 1977, Page(s):1117 - 1120
| | PDF (655 KB)

A system of three computer programs is described which process data from far-field amplitude antenna pattern measurements to give partial and total directivity mappings (where partial directivityÂ¿ refers to one polarisation only). The measurement data is acquired by sampling the radiation distribution over a spherical region enclosing the test antenna, first in one polarisation and then in the o... View full abstract»

• ### Erratum: Reappraisal of computer-corrected network analyser design and calibration

Publication Year: 1977
| PDF (60 KB)
• ### Erratum: Self-excitation of dual-excited synchronous machines

Publication Year: 1977
| PDF (60 KB)
• ### Noise reduction in integrated Norton amplifiers

Publication Year: 1977, Page(s):1121 - 1124
| | PDF (500 KB)

The effects of current-mirror emitter degeneration on monolithic Norton amplifier operation are described. The limits on practical improvement in noise performance obtainable are discussed. An active filter is used to illustrate the substantial noise reduction that can be achieved over standard handbook designs, and the predictions are verified experimentally. View full abstract»

• ### Combined effects of terrestrial diffraction and ionospheric reflection on medium-frequency sky wave propagation

Publication Year: 1977, Page(s):1125 - 1126
| | PDF (251 KB)

A theoretical analysis is made on the titled subject as an extension of the classical theory (elaborated by H. Bremmer) of the ionospheric propagation. A physical parameter, which is akin to the conventional convergence or divergence coefficient introduced by Bremmer, is formulated in an approximate integral representation which is applicable at low to negative angles of departure/arrival, and the... View full abstract»

• ### Rectifier circuit performance: some new approximate formulas

Publication Year: 1977, Page(s):1127 - 1134
Cited by:  Papers (4)
| | PDF (683 KB)

New formulas are offered for the calculation of the performance parameters of halfwave and fullwave rectifiers: average output voltage, effective and peak values of diode current, peak-peak ripple and troughÂ¿ value of output voltage (the lower extreme of the ripple). These are expressed in terms of the impedance and frequency of the a.c. source, the size of the reservoir capacitor and the load c... View full abstract»

• ### Interference suppression by multi-interval integration in analogue-digital convertors

Publication Year: 1977, Page(s):1135 - 1138
| | PDF (440 KB)

A generalised conception of multi-interval integration for the solution of the problem of interference suppression in integrating analogue-digital (a.d.) convertors is presented. Three types of multi-interval integration are described namely nonoverlapped, overlapped and combined. The characteristics of a number of corresponding integration techniques are given in tabular form for several indices ... View full abstract»

• ### Differential coding of Pal video signals using intrafield prediction

Publication Year: 1977, Page(s):1139 - 1147
Cited by:  Papers (1)
| | PDF (1460 KB)

The paper discusses the application of differential pulse-code modulation (d.p.c.m.) and hybrid d.p.c.m./p.c.m. coding as a means of reducing the bit rate required for broadcast-quality System I (Pal, 625-line, 5.5 MHz) video signals. In the d.p.c.m. codes investigated, each codeword indicated the difference in magnitude between a sample of a video signal and a prediction of this sample based on s... View full abstract»

• ### High-speed regeneration of phase-shift keying signals using phase-script logic

Publication Year: 1977, Page(s):1148 - 1154
| | PDF (866 KB)

A novel method of regeneration of digital phase-modulated (phase-shift keying) signals is proposed, analysed and demonstrated using a parametric-subharmonic oscillator (p.s.o.) as a phase-script logic element. This technique of regeneration proceeds at carrier frequency without the need for down-conversion. An analysis of the switching performance of such regenerators is presented and applied to t... View full abstract»

• ### Crossmodulation in ring modulators

Publication Year: 1977, Page(s):1155 - 1159
| | PDF (536 KB)

This paper deals with the crossmodulation in ring modulators. By means of an approximate calculation the effective half-value of the e.m.f. of the undesired signal at the input of the ring modulator, giving rise to a crossmodulation factor of 1%, is investigated as a function of the maximum available power of the oscillator. The results of the theory used here show very good agreement with the mea... View full abstract»

• ### Equivalent network of a variable-height post in a rectangular waveguide

Publication Year: 1977, Page(s):1160 - 1162
Cited by:  Papers (2)
| PDF (297 KB)
• ### Net coding gain of error-correcting codes

Publication Year: 1977
| PDF (101 KB)
• ### Net coding gain of error-correcting codes

Publication Year: 1977
| PDF (101 KB)
• ### Turbogenerator short circuits with delayed current zeros

Publication Year: 1977, Page(s):1163 - 1169
Cited by:  Papers (4)
| | PDF (891 KB)

It has been observed in practice that, following a fault at the terminals of a synchronous generator, the armature currents may not pass through zero for some considerable time, and this phenomenon may result in serious damage to a generator breaker attempting to interrrupt the fault current. In this paper, the various factors which affect the non-zero time are investigated. An analytical study is... View full abstract»

• ### Implementation of new approach to determination of synchronous-machine parameters from tests

Publication Year: 1977, Page(s):1170 - 1178
Cited by:  Papers (16)
| | PDF (1285 KB)

This is a follow-up to a published paper dealing with a new theory on the analysis of the results of tests on generators in order to determine electromagnetic parameters. The application of the new theory to tests such as sudden stator short-circuit tests, stator-decrement tests, rotor-decrement tests and frequency-response tests is discussed, and examples of the analysis of such tests are present... View full abstract»

• ### Discussion on "Transient voltages and currents in series-compensated e.h.v. lines"

Publication Year: 1977, Page(s):1178 - 1180
| PDF (553 KB)
• ### Heating in transformer cores due to radial leakage flux. Part 2: Computed results

Publication Year: 1977, Page(s):1181 - 1186
Cited by:  Papers (1)
| | PDF (859 KB)

The experimental loss and flux-density distributions, given in the companion paper for two full-scale transformer core-leg models, are compared with theoretical results obtained by computer. The computer program provides a 3-dimensional solution of the leakage flux distribution, both outside and inside the core. The flux penetration into the core leg is calculated using an anisotropic-core model, ... View full abstract»

• ### Three-dimensional theory of eddy-current couplings with copper-faced loss drums

Publication Year: 1977, Page(s):1187 - 1196
Cited by:  Papers (3)
| | PDF (1046 KB)

The paper gives a 3-dimensional theory of eddy-current couplings with solid-iron drums, with a layer of copper at the airgap surface. It is shown that the iron has a significant effect on performance and that this effect can be adequately accounted for using linear theory. General double-Fourier series are derived to describe the field distributions in the drum and airgap. These are then successiv... View full abstract»

• ### Construction of Lyapunov function for power systems

Publication Year: 1977, Page(s):1197 - 1202
Cited by:  Papers (6)
| | PDF (575 KB)

A systematic procedure of constructing Lyapunov functions for power systems is considered. A new approach is presented, which uses a construction technique of the Lagrange's function resulting from 2nd-order ordinary differential equations. The application of this new method to power-system transient-stability problems is illustrated by considering a single-machine system, taking into account the ... View full abstract»

• ### Behaviour of contactors protected by fuses during short-circuit currents

Publication Year: 1977, Page(s):1203 - 1206
| | PDF (428 KB)

The behaviour of contactors protected by fuses under short-circuit currents is analysed using a simple model to represent the electric circuit and the contactor. The resulting performance equations are given and an example of application is illustrated. Experimental results are reported which agree well with those computed. The existence is confirmed of a definite range of prospective short-circui... View full abstract»

• ### Some new solutions to ferroresonance problem in power system

Publication Year: 1977, Page(s):1207 - 1211
Cited by:  Papers (1)
| | PDF (484 KB)

A parametric equation of the envelope on the GÂ¿1(jw) plane for the general polynomial-type nonlinearity is derived. An analytical method has been suggested for the evaluation of threshold frequency for the occurrence of ferroresonance. Mathematical equations have been deduced for computing the jump-to points for quintic nonlinearity. A generalised equation for asymptotic values of percentage unst... View full abstract»

• ### Theory of resistance commutation with particular reference to carbon-fibre brushes

Publication Year: 1977, Page(s):1212 - 1214
| | PDF (380 KB)

Commutation in small machines depends on changing brush-segment resistances. The manner in which these resistances change, and the consequent brush current densities, can be influenced by the shape of the commutator segments. Simple equations are derived from the current density during commutation, and these are used to show that specially shaped segments can lead to lower maximum values. This con... View full abstract»

• ### Unifying approach to the static torque of stepping-motor structures

Publication Year: 1977, Page(s):1215 - 1224
Cited by:  Papers (10)
| | PDF (1496 KB)

Important stepping-motor structures are compared and their logical relationship to a basic doubly-salient machine is demonstrated. This leads to a single expression for holding torque, applicable to the majority of motors, comprising a product of the following terms: (a) a theoretical limiting mean torque, (b) a factor allowing for finite excitation, (c) the fraction of rotor volume effectively ut... View full abstract»

## Aims & Scope

The Proceedings of the Institution of Electrical Engineers was published by the IET between 1963 and 1979.

Full Aims & Scope