Showing papers in "Electronics Letters in 1969"
TL;DR: An explicit formula for the inversion of the Laplace transform is derived in this article, and the formula permits the inverse to be readily evaluated numerically, which is the case of the inverse in this paper.
Abstract: An explicit formula for the inversion of the Laplace transform is derived The formula permits the inverse to be readily evaluated numerically
320 citations
TL;DR: In this paper, a novel technique has been developed for measurement of dispersion and wavelength in microstrip transmission line laid down on an Al2O3 substrate, which can be satisfactorily used at far higher frequencies.
Abstract: A novel technique has been developed for measurement of dispersion and wavelength in microstrip transmission line laid down on an Al2O3 substrate. The frequency range so far investigated has been 4-12GHz, although the method could be satisfactorily used at far higher frequencies. The measurement accuracy is better than within 1%. Techniques for producing well matched transitions to any thickness substrate have also been established.
172 citations
TL;DR: In this paper, the mode patterns of circular disc resonant sections are analyzed and the radiation losses are expected to be small for the dominant mode, which would therefore have the highest Q value.
Abstract: Mode patterns of circular disc resonant sections are analysed. Radiation losses are expected to be small for the dominant mode, which would therefore have the highest Q value.
155 citations
TL;DR: In this article, an analytical demonstration of image theory is given for the case where a vertical magnetic dipole is located over a dissipative half-space, provided that distances are large with a skin depth in the ground yet small compared with the wavelength.
Abstract: An analytical demonstration of image theory is given for the case where a vertical magnetic dipole is located over a dissipative half-space. It is shown that the image concept is valid, provided that distances are large with a skin depth in the ground yet small compared with the wavelength.
79 citations
TL;DR: In this article, a numerical iterative scheme is presented for the solution of the 1- and 2-dimensional semiconductor d.c. transport equations, applied to an n-p-n transistor structure.
Abstract: A numerical iterative scheme is presented for the solution of the 1- and 2-dimensional semiconductor d.c. transport equations. This scheme is applied to an n-p-n transistor structure. Input data are geometry, doping profile, boundary conditions and, optionally, mobility dependencies and generation-recombination law.
75 citations
TL;DR: In this article, a method of determining small variations in delay time of acoustic surface waves is described which is both simple and accurate as an example of the technique applied to determining the temperature vanation of delay times of surface waves propagating in the z direction on a y face of lithium niobate.
Abstract: A method of determining small variations in delay time of acoustic surface waves is described which is both simple and accurate As an example, the technique is applied to determining the temperature vanation of delay time of surface waves propagating in the z direction on a y face of lithium niobate
65 citations
TL;DR: A simple method of designing a stable (n – m)-state observer for an n-state linear deterministic system with m independent outputs is presented.
Abstract: A simple method of designing a stable (n – m)-state observer for an n-state linear deterministic system with m independent outputs is presented
64 citations
TL;DR: Bulk and surface waves are strongly coupled at a corrugated surface as mentioned in this paper, and experiments have demonstrated transduction losses of less than 1dB and bandwidths of 20% Methods of implementation at high frequencies are discussed
Abstract: Bulk and surface waves are strongly coupled at a corrugated surface Experiments have demonstrated transduction losses of less than 1dB and bandwidths of 20% Methods of implementation at high frequencies are discussed
60 citations
TL;DR: In this paper, it was shown that the validity of the Rayleigh hypothesis is dependent on the distribution of singularities in the analytic continuation of the exterior scattered field; the hypothesis is fulfilled if, and only if, these are concentrated in a sufficiently small domain.
Abstract: It is shown that the validity of the Rayleigh hypothesis is dependent on the distribution of singularities in the analytic continuation of the exterior scattered field; the hypothesis is fulfilled if, and only if, these are concentrated in a sufficiently small domain. Conclusions reached by Burrows in a recent letter are criticised.
58 citations
TL;DR: A fast combinational circuit is described which can be used both as a multiplier and as an adder, either separately or together, giving a parallel binary output.
Abstract: A fast combinational circuit is described which can be used both as a multiplier and as an adder, either separately or together, giving a parallel binary output. The structure, which is completely iterative in terms of both cell logic and cell-interconnection pattern, is advantageous in large-scale integration.
56 citations
TL;DR: In this article, the characteristics of the switching phenomena observed in chalcogenide glasses are described in terms of the Joule heating within the material, and the model is also used to explain the nonohmic behaviour observed in the low-conductance state.
Abstract: The characteristics of the switching phenomena observed in chalcogenide glasses are described in terms of the Joule heating within the material. Calculations for an infinite-slab geometry are given. The model is also used to explain the nonohmic behaviour observed in the low-conductance state.
TL;DR: A practical method is described for encoding an unrestricted binary signal into a form suitable for transmission through a binary regenerated signal path while incurring only a small increase in modulation rate.
Abstract: A practical method is described for encoding an unrestricted binary signal into a form suitable for transmission through a binary regenerated signal path while incurring only a small increase in modulation rate
TL;DR: In this paper, two active RC networks are presented for the realisation of a second-order all-pass function, each of which uses one differential-input operational amplifier and two RC networks.
Abstract: Two active networks are presented which are suitable for the realisation of a second-order allpass function. Each uses one differential-input operational amplifier and RC networks. The realisation is achieved to within a constant multiplier always smaller than unity.
TL;DR: Two examples of filters using Rayleigh waves, at the frequencies of 25 MHz and 150 MHz, are described in this paper, where the shape, almost rectangular, of the frequency response is determined by drawing one transducer.
Abstract: Two examples of filters using Rayleigh waves, at the frequencies of 25 MHz and 150 MHz, are described. The shape, almost rectangular, of the frequency response is determined by drawing one transducer.
TL;DR: In this paper, it was shown that the Rayleigh hypothesis is exact, although, in general, it is necessary to interpret it in a generalised function sense, i.e., the point-matching method is equivalent to the exact extended-boundary-condition method.
Abstract: Methods based on the Rayleigh hypothesis (e.g. the point-matching method) for numerically solving wave-diffraction problems are shown to be equivalent to the exact extended-boundary-condition method. It is concluded that the Rayleigh hypothesis is exact, although, in general, it is necessary to interpret it in the generalised function sense.
TL;DR: In this paper, the design formulas for realising any biquadratic voltage transfer function are given, and the configuration uses ten or fewer resistors, two capacitors and four single-ended operational amplifiers.
Abstract: Complete design formulas for realising any biquadratic voltage transfer function are given. The configuration uses ten or fewer resistors, two capacitors and four single-ended operational amplifiers. The realisation achieves extremely low sensitivity and can readily be used in realising stable high Q factor active filters up to 100kHz.
TL;DR: An external cavity coupled to a continuously operating GaAs diode laser has been found to cause modulation of the light output at a frequency within the range of 0.6-2.2GHz.
Abstract: An external cavity coupled to a continuously operating GaAs diode laser has been found to cause modulation of the light output at a frequency within the range of 0.6–2.2GHz. The modulation depth is close to 100% and the linewidth is 200kHz.
TL;DR: In this article, the input impedance of a monopole antenna in a rectangular waveguide is investigated experimentally, and it is found that theoretical results based on the assumption of a sinusoidal current distribution are in good agreement for monopole lengths up to about 0.6 of the guide height and about 1/4 λ 0.
Abstract: The input impedance of a monopole antenna in a rectangular waveguide is investigated experimentally. It is found that theoretical results based on the assumption of a sinusoidal current distribution are in good agreement for monopole lengths up to about 0.6 of the guide height and about 1/4 λ0. For longer monopoles, a more accurate theory should be sought.
TL;DR: In this paper, a magnetoelastic surface wave is shown to exist in an elastically isotropic ferrite, e.g. y.i.d., and exhibits a non-reciprocal behaviour.
Abstract: A magnetoelastic surface wave is shown to exist in an elastically isotropic ferrite, e.g. y.i.g. The wave exhibits a nonreciprocal behaviour, and is found to have no counterpart in a purely elastic medium.
TL;DR: In this article, an approximate analysis of fields in a corrugated horn is considered using spherical hybrid modes, and a procedure is described for the determination of the horn radiation pattern.
Abstract: An approximate analysis of fields in a corrugated horn is considered using spherical hybrid modes. Under the special condition where the slots are about a quarter-wavelength deep, the approximations are slight in the far-field region of the horn. Solutions are presented for the lowest-order spherical hybrid modes, and a procedure is described for the determination of the horn radiation pattern. A first step in the procedure involves the calculation of the hybrid-mode field in the horn aperture. Because diffraction will be minimal in wide-angle corrugated horns, the aperture and radiation patterns should be similar when the far-field approximation applies. This feature is verified for a 120° horn making use of experimental results due to Kay.
TL;DR: In this article, a Fourier analysis of a symmetrically placed microstrip line in a dielectric-loaded guide is performed, and the results of the dispersion for the fundamental even-odd Hz mode are presented.
Abstract: A Fourier analysis of a symmetrically placed microstrip line in a dielectric-loaded guide is performed. Computed results of the dispersion for the fundamental even Ez-odd Hz mode are presented.
TL;DR: The letter presents a method of calculating the first- and second-order sensitivities of a linear time-invariant non-reciprocal network using only the single matrix inversion involved in the original network analysis.
Abstract: The letter presents a method of calculating the first- and second-order sensitivities of a linear time-invariant non-reciprocal network using only the single matrix inversion involved in the original network analysis.
TL;DR: Complex solutions to the characteristic equation for wave propagation along a lossless dielectric cylinder are shown in this article, suggesting that the well known general features of leaky waves may be exhibited by this particular structure.
Abstract: Complex solutions to the characteristic equation for wave propagation along a lossless dielectric cylinder are shown to exist, suggesting that the well known general features of leaky waves may be exhibited by this particular structure The influence of losses is discussed
TL;DR: The letter defines an algorithm and examines its performance in this task of initialising a learning machine and finds a method of providing a good starting state for the learning machine.
Abstract: Pattern recognition has usually been regarded as a two-part process requiring both measurement and classification. It has also been accepted by many workers that the classifier can best be designed using an automatic learning process. However it is well known that many of the proposed learning schemes sometimes fail to realise the most efficient use of the available storage. This difficulty usually arises whenever the initial classifier was a poor approximation to the teacher. The design of the classifier using such learning techniques would clearly be more successful if a method could be found of providing a good starting state for the learning machine. The letter defines an algorithm and examines its performance in this task of initialising a learning machine.
TL;DR: Four building blocks have been found that realise the biquadratic transfer function T(s) with very low sensitivities to variations in the passive and active components, and with the possibility of trimming σo, ωoo, σop and ωop independently each by one resistor.
Abstract: Four building blocks have been found that realise the biquadratic transfer function T(s)=K s2 + 2σos + σoo2/s2 + 2σps + σop2 with very low sensitivities to variations in the passive and active components, and with the possibility of trimming σo, ωoo, ωop and ωop independently each by one resistor. The networks may be manufactured in standardised integrated blocks which may be trimmed for specific applications.
TL;DR: In this article, a general method for handling partial products in a parallel multiplier is proposed, which leads to a network of AND gates and full adders, availables as i.c.s which can have an operation time of less than 10 ns per bit.
Abstract: A general method for handling partial products in a parallel multiplier is proposed. It leads to a network of AND gates and full adders, availables as i.c.s which can have an operation time of less than 10 ns per bit of the result.
TL;DR: In this paper, the propagation behavior of a corrugated cylinder is considered with particular reference to the application of such structures to hybrid-mode feeds for large reflector antennas, and a procedure for achieving a balanced hybrid condition in the horn aperture is discussed.
Abstract: The propagation behaviour of a corrugated cylinder is considered with particular reference to the application of such structures to hybrid-mode feeds for large reflector antennas. Results are presented which relate to the design of narrow-flare-angle horns of circular cross-section. These include the parametric dependence of a number of special points on the propagation curves. A procedure for achieving a balanced hybrid condition in the horn aperture is discussed following the proposal made by Bryant.
TL;DR: In this paper, a point-matching solution for the surface current density (not the scattered field) is shown to be rigorously based on the Rayleigh hypothesis for electromagnetic scattering.
Abstract: A recent suggestion, that the Rayleigh hypothesis for electromagnetic scattering is exact, is shown, by counterexample, to be questionable. A point-matching solution for the surface current density (not the scattered field) is shown to be rigorously based. The solution is similar to that for the scattered field derived from the Rayleigh hypothesis.
TL;DR: In this paper, a Green's function of the vector potential for a microstrip is derived on the basis of the image theory after Silvester and the duality property of electric and magnetic fields of the TEM mode.
Abstract: A Green's function of the vector potential for a microstrip is derived on the basis of the image theory after Silvester and the duality property of electric and magnetic fields of the TEM mode. It is also shown that the stationary equation similar to the variational equation for the electrostatic capacitance of the microstrip is given for its inductance with a magnetic substrate.
TL;DR: In this paper, a CO2-N2-He laser was described in which the discharge plasma was excited in the volume between two coaxial silica tubes by means of a radial r.c.f. field.
Abstract: A CO2-N2-He laser is described in which the discharge plasma was excited in the volume between two coaxial silica tubes by means of a radial r.f. field. Additional power was fed into the plasma by a longitudinal d.c. field applied to internal electrodes. With an outer tube 46.5 mm in diameter and 1.2m long, an output power of 250W was obtained at 12% efficiency.