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# Electronics Letters

## Filter Results

Displaying Results 1 - 21 of 21
• ### New c.c.d. programmable transversal filter

Publication Year: 1977, Page(s):521 - 523
Cited by:  Papers (13)
| | PDF (502 KB)

A c.c.d. transversal-filter structure is described which is capable of processing signals at high data rates. The tap weights can be programmed as digital words. A 32-stage prototype device has been tested at clock rates up to 20 MHz; operation at even higher data rates appears feasible. View full abstract»

• ### Leakage factor and burst noise in transistor arrays

Publication Year: 1977, Page(s):523 - 524
| | PDF (181 KB)

Investigation of 4-transistor arrays in which the devices are very well matched at emitter currents above 100 nA has revealed correlation between burst noise and the departure from matchnessÂ¿ at lower currents. A figure of merit based on the leakage currents ICBO,ICEO is introduced to compare individual devices and arrays. View full abstract»

• ### Stepped-impedance phase shifters

Publication Year: 1977, Page(s):524 - 525
| | PDF (225 KB)

A coupled-line phase shifter can be decomposed in two lines of stepped characteristic impedances, interconnected by a 180Â° hybrid. This network permits phase responses which cannot be realised with coupled lines. Practical simplifications are possible by omitting one of the two lines or by using a 90Â° hybird. View full abstract»

• ### Horizontal shear surface waves on a laminated composite

Publication Year: 1977, Page(s):525 - 526
| | PDF (342 KB)

The existence is demonstrated of a new type of acoustic surface wave that has a horizontally polarised shear displacement and which propagates along the free surface of a halfspace comprised of a periodically layered composite. This wave contrary to other types of dispersive waves, has unique bandpass and bandstop dispersive characteristics that suggest new filter applications. View full abstract»

• ### Properties of X-ray guides

Publication Year: 1977, Page(s):527 - 529
Cited by:  Papers (1)
| | PDF (494 KB)

The transmission and power enhancement of X-rays in cylindrical waveguides are investigated as functions of the length and bore diameter. Measurements were made at a wavelength of 1.54 Ã using hollow, lead glass tubing. Discrepancies between the observed values and theoretical predictions may be ascribed to surface roughness and variations in the guide dimensions. View full abstract»

• ### High-bit-rate pulse regeneration and injection laser modulation using a diode circuit

Publication Year: 1977, Page(s):529 - 530
Cited by:  Papers (1)
| | PDF (395 KB)

The push-pull diode circuit investigated regenerates pulse trains near 1 Gbit/s with a power amplification of 8.4 dB. As a particular application, the direct modulation of a laser diode was carried out with this circuit at a bit rate of 1 Gbit/s. View full abstract»

• ### Calculation of wideband random-noise powers in television systems

Publication Year: 1977, Page(s):530 - 532
| | PDF (323 KB)

Expressions are derived for the loss experienced by wideband random noise with various power-density spectra in networks associated with television transmission systems. Values are tabulated for television system I with the total noise power modified by each of two weighting networks used in noise measuring circuits and/or the de-emphasis network used to complement pre-emphasis with f.m. radio tra... View full abstract»

• ### Modes in curved step-index optical fibres

Publication Year: 1977, Page(s):532 - 535
Cited by:  Papers (2)
| | PDF (562 KB)

By using parabolic, instead of circular, cylindrical co-ordinates the field distributions of the natural modes of curved step-index fibres can be described completely, yet simply. The mode caustics corresponding to the geometrical guiding limit of the equivalent rays of curved fibre can be clearly demonstrated. Near-field mode patterns and caustics obtained experimentally are in excellent agreemen... View full abstract»

• ### New type of constant-impedance bandpass microwave filter based on the commutating principle

Publication Year: 1977, Page(s):535 - 536
| | PDF (195 KB)

The basic principles are presented for a class of nonreflective bandpass microwave filters or amplitude equalisers that comprise cascades of power-divider elements with differentialphase networks interposed between them. These filters exhibit low transmission loss and minimal group-delay variation. View full abstract»

• ### Differential pulse regenerator driven by 1 Gbit/s p.c.m.-type signals from an avalanche photodiode

Publication Year: 1977, Page(s):536 - 537
Cited by:  Papers (3)
| | PDF (224 KB)

A hybrid-integrated pulse regenerator circuit, essentially employing an ultrabroadband 180Â° hybrid, step-recovery diodes and bipolar-transistor emitter followers, was operated by 1 Gibt/s signals delivered from an avalanche photodiode. A voltage gain of 20 dB could be measured on a single regenerator stage. RZ output pulses of halfwidths down to 100 ps were obtained, with the pulse shape being in... View full abstract»

• ### Modelling of Gunn-domain effects in GaAs m.e.s.f.e.t.s

Publication Year: 1977, Page(s):537 - 539
Cited by:  Papers (7)
| | PDF (379 KB)

GaAs m.e.s.f.e.t. [S22] values larger than unity have been measured from 1 to 10 GHz in the region where the ID/VD curves display a negative slope. An explanation of this phenomenon is proposed in terms of Gunn-domain formation. An equivalent-circuit model which includes this effect is presented and discussed. View full abstract»

• ### Commutativity of time-varying systems

Publication Year: 1977, Page(s):539 - 540
| | PDF (184 KB)

Results are given concerning the commutativity of time-varying systems. It is shown that a constant-parameter dynamic system does not commute with a time-varying dynamic system. Conditions are derived for low-order time-varying systems to commute. A general condition for a set of time-varying systems to commute is the existence of a variable time scaling which reduces the time-varying systems to a... View full abstract»

• ### Medium-numerical aperture low-pulse-dispersion fibre

Publication Year: 1977, Page(s):540 - 542
Cited by:  Papers (2)
| | PDF (326 KB)

A multilayer graded-index fibre with a numerical aperture of 0.2 which shows low modal dispersion has been fabricated with the aid of the plasma activated c.v.d. process. At 905 nm, the f.w.h.m. modal broadening was found to be about 150 ps/km, obtained for full mode excitation. View full abstract»

• ### Model for the excitation of 1/f noise by high-frequency a.c. signals

Publication Year: 1977, Page(s):542 - 544
Cited by:  Papers (1)
| | PDF (325 KB)

A model is presented for the excitation of 1/f noise in carbon and semiconductor resistors by high-frequency a.c. signals. The model does not require special theories on 1/f noise; the observed 1/f noise is attributed, as usual, to resistance fluctuations. View full abstract»

• ### Optical silicon lifetime measurements in heavily doped diffused regions

Publication Year: 1977, Page(s):544 - 545
Cited by:  Papers (2)
| | PDF (241 KB)

Monochromatic visible light at various wavelengths was used to generate photocurrent in a silicon n+-p diffused diode. A numerical model which includes electric field, heavy doping band gap reduction and doping level mobility dependence was used with fitting techniques to determine the carrier lifetime in the n+-region at each wavelength. View full abstract»

• ### Intensity modulation of light transmitted in curved optical fibres

Publication Year: 1977, Page(s):545 - 546
Cited by:  Papers (1)
| | PDF (343 KB)

Coupled-mode theory is used to explain the intensity modulation of transmitted light which results from small changes in the radius of curvature. It is shown that the mode coupling induced by bends in small-V fibres introduces an uncertainty into light-transmission measurements. View full abstract»

• ### Subjective quality of television pictures impaired by linear waveform distortion

Publication Year: 1977, Page(s):546 - 548
Cited by:  Papers (1)
| | PDF (467 KB)

Existing subjective results relating to the effect of undistorted echo in television have been applied to determine the psychophysical relationship between subjective picture quality and the objective measure of linear waveform distortion, termed the K-ratingÂ¿. Values of the coefficients G and KM are given, which, starting with a known value of K, permit estimates to be made of mean picture qual... View full abstract»

• ### Winograd's algorithm applied to number-theoretic transforms

Publication Year: 1977, Page(s):548 - 549
Cited by:  Papers (1)
| | PDF (429 KB)

We show how to perform a number-theoretic transform (n.t.t.) using an algorithm analogous to that of S. Winograd for computing the discrete Fourier transform (d.f.t.). Using this algorithm, the range of data lengths and word lengths is much larger than that available with conventional fast n.t.t.s. View full abstract»

• ### Simplified GaAs m.e.s.f.e.t. model to 10 GHz

Publication Year: 1977, Page(s):549 - 551
Cited by:  Papers (50)
| | PDF (359 KB)

A simplified design-oriented equivalent circuit for the GaAs m.e.s.f.e.t. is presented. Its relation to a common, but more complex, model is derived and characteristics are compared. Element values are easily determined from measurements, and the simple model shows good agreement with measured parameters to 10 GHz for 1 Â¿m-gate m.e.s.f.e.t.s. View full abstract»

• ### Subjective data for random noise measured through the new CMTT unified weighting network for television

Publication Year: 1977, Page(s):551 - 553
| | PDF (424 KB)

Parameters are calculated that describe the subjective effect of noise on colour-television pictures in terms of the noise level as measured through the new CMTT unified weighting network. For the `averageÂ¿ spectral shape likely to occur in practice, signal/noise ratios are given at a number of mark points expressed in terms of summable subjective impairment (imp) units. View full abstract»

• ### High-order mode coupler for millimetre wavelengths

Publication Year: 1977, Page(s):553 - 554
| | PDF (228 KB)

A new type of injection filter has been developed that can be used for local-oscillator injection in millimetre-wave mixers and other narrowband diplexing applications. The insertion loss for nonresonance frequencies is typically less than 0.25 dB. For the selected resonant modes, the coupler acts as a 3 dB power divider. Insertion losses of 1.5 dB or less can be reached at these frequencies. View full abstract»

## Aims & Scope

Electronics Letters is internationally renowned for its rapid communication of new developments and emerging topics across the broad and interdisciplinary field of modern electronics and electrical engineering.

Full Aims & Scope

## Meet Our Editors

Editors-in-Chief

Professor Chris Toumazou
Director of the Biomedical Institute
Imperial College, London, UK

Professor Ian White
Head of Photonics Research
University of Cambridge, UK