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# Electronics Letters

## Filter Results

Displaying Results 1 - 24 of 24
• ### Easy and accurate method for the characterisation of dielectric materials at X-band

Publication Year: 1976, Page(s): 573
| | PDF (115 KB)

A method of characterising dielectric materials at microwave frequencies is described. The technique overcomes the problem of airgaps in the commonly used filled-cavityÂ¿ technique. Results of measurements of the permittivity/temperature characteristics of both quartz and a titanium loaded composite dielectric with a negative slope are presented. The accuracy of the technique is described and a h... View full abstract»

• ### Theory on long time delays, Q-switching and related phenomena in GaAs junction lasers

Publication Year: 1976, Page(s):574 - 575
Cited by:  Papers (2)
| | PDF (290 KB)

We present a theory that explains long time delays. Q-switching and related phenomena in GaAs junction lasers, based only on processes known to occur in these lasers. View full abstract»

• ### Experimental 4Ã4 optical switching network

Publication Year: 1976, Page(s):575 - 577
Cited by:  Papers (25)
| | PDF (621 KB)

An optical waveguide 4Ã4 switching network fabricated by integrating five switched directional couplers with stepped Â¿Ã reversal on a single LiNbO3 substrate is reported. The maximum crosstalk observed on any output waveguide was down by 18 dB. View full abstract»

• ### Compensation of microstrip bends by using square cutouts

Publication Year: 1976, Page(s):577 - 579
| | PDF (409 KB)

An alternative to the commonly used technique of mitring for compensation of microstrip bends is described. Experimental data are presented for the case where a square cutout is removed, at either the inner or outer corner of the 90Â° bend. This approach eases artwork generation. View full abstract»

• ### Dispersionless coupled microstrip over fused silica-like anisotropic substrates

Publication Year: 1976, Page(s):579 - 580
Cited by:  Papers (16)
| | PDF (212 KB)

A Green's function for coupled microstrip with cover over anisotropic substrates has been obtained in integral and series form. It is applied to obtain the even- and odd-mode characteristic impedances and normalised phase velocities for fused silica-like substrates. It is shown that, for certain anisotropies, the transmission lines are dispersionless. View full abstract»

• ### Frequency/stress sensitivity of s.a.w. resonators

Publication Year: 1976, Page(s):580 - 582
Cited by:  Papers (5)
| | PDF (417 KB)

Surface-acoustic-wave resonators can be used as stress sensors for measuring force and pressure. Experiments at 160 MHz using rotated y-cut substrates indicate that larger linear changes in resonator frequency can be obtained by deforming the substrate. The s.a.w. transducers, besides being small in size, are also stable in frequency. View full abstract»

• ### V-groove power junction field-effect transistor for v.h.f. applications

Publication Year: 1976, Page(s):582 - 583
Cited by:  Papers (2)
| | PDF (416 KB)

A new high-power, high-frequency junction field-effect transistor with a nonplanar V-shaped channel fabricated by preferential etching of Â¿100Â¿ silicon is described. The structure of this transistor is very simple, requires only three photolithographic masking steps and results in a very high packing density. A device having an effective channel length of 2 Â¿m was fabricated. This transistor ex... View full abstract»

• ### High-resolution guided radar system

Publication Year: 1976, Page(s):583 - 584
Cited by:  Papers (3)
| | PDF (360 KB)

A high-resolution guided radar system with commercial application in intrusion and obstacle detection is described. View full abstract»

• ### Linearisation of microwave point-contact-detector characteristics

Publication Year: 1976, Page(s): 585
| | PDF (147 KB)

The characteristics of microwave measuring-grade point-contact detectors can be linearised over a wide dynamic range with a simple circuit with only one adjustable parameter for nonlinearity. The need for matching of detectors is also largely eliminated. View full abstract»

• ### S.A.W. co-ordinate sensor

Publication Year: 1976, Page(s):586 - 587
Cited by:  Papers (5)
| | PDF (2003 KB)

The co-ordinates of the tip of a pencil lightly pressed on a piezoelectric crystal are deduced from measurements of the time necessary for surface acoustic waves (s.a.w.) to propagate from interdigital transducers to the pencil. Graphs drawn by the pencil moving on the crystal can be stored in a computer at a fast rate. Examples of data acquisition are given. View full abstract»

• ### Better phase-modulation error performance using trellis phase codes

Publication Year: 1976, Page(s):587 - 588
Cited by:  Papers (11)
| | PDF (284 KB)

We construct phase codes for use in phase- and frequency-shift modulation. A trellis structure allows simple decoding using the Viterbi algorithm. Even short codes give a large improvement in error performance. View full abstract»

• ### Moments of an output feedback system

Publication Year: 1976, Page(s):588 - 589
Cited by:  Papers (1)
| | PDF (245 KB)

The moments of an output feedback system are given explicitly in terms of the moments of the open-loop system and the feedback gain. From these expressions, it is clear that the moments of a high-order system and reduced model are the same under output feedback law provided that they are identical for the open-loop case. View full abstract»

• ### Phase normalised m-sequences with the inphase decimation property {m(k)}={m(2k)}

Publication Year: 1976, Page(s):590 - 591
Cited by:  Papers (1)
| | PDF (244 KB)

The inphase decimation property of a binary sequence {f(k)} is defined such that f(k)=f(2k) for all k=0, 1, 2,Â¿ Given a primitive generator polynomial G(D) of degree r with its even and odd parts Ge(D) and Go(D), it is shown that there is a unique version of the corresponding m-sequence with this inphase decimation property, resulting as Ge(D)/G(D) if r is odd and Go(D)/G(D) if r is even. An m-se... View full abstract»

• ### ZOGMOST: an improved m.o.s.t. for c.c.d. peripheral circuits

Publication Year: 1976, Page(s):591 - 592
Cited by:  Papers (1)
| | PDF (291 KB)

An improved formation for m.o.s. transistors fabricated with the shadow-etchÂ¿ c.c.d. process is reported. The narrow self-aligned gaps produced by the process are used to provide an additional screen gate, which allows the gate-drain overlap capacitance to be minimised, thereby improving the frequency characteristics of linear and digital m.o.s. circuits. Depending on the gain of the stage invol... View full abstract»

• ### Bandstop iris for rectangular waveguide

Publication Year: 1976, Page(s):592 - 594
Cited by:  Papers (13)
| | PDF (454 KB)

A description is given of a bandstop resonant iris for rectangular waveguide. An approximate theory is developed to predict the frequency response of the iris, and predicted results are shown to compare well with measured data. View full abstract»

• ### Detection of shallowly buried objects

Publication Year: 1976, Page(s):594 - 595
| | PDF (295 KB)

Electromagnetic detection of nonmetallic objects buried near the earth's surface is hampered by the strong signal returned from the surface. Pointing a directive antenna forward is shown experimentally to greatly reduce the surface return, thus improving the ability of the system to detect buried targets. View full abstract»

• ### ZnO film concave transducer for focusing radiation of microwave ultrasound

Publication Year: 1976, Page(s):595 - 596
Cited by:  Papers (6)
| | PDF (291 KB)

A ZnO piezoelectric film has been satisfactorily deposited on a concave substrate of a gold hemispherical shell to produce a concave transducer for microwave ultrasound. The fabrication process of the concave transducer, with a focal distance of 5Â¿9 mm, and also experiments on focusing radiation in water at 100 MHz. are described. View full abstract»

• ### Beam squint in a linearly polarised offset reflector antenna

Publication Year: 1976, Page(s):596 - 597
Cited by:  Papers (1)
| | PDF (263 KB)

A beam squint has been found to occur in the field radiated by an offset paraboloid antenna illuminated by a feed with linear polarisation in the plane of offset. The squint, whose existence has been confirmed by computed and measured radiation patterns, occurs in the offset plane, and is typically 0.03 of a beamwidth for a reflector of 6-wavelengths diameter. An assessment is given of the likely ... View full abstract»

• ### Inexpensive equipment for driving GaAs lasers with 100 ps risetime pulses

Publication Year: 1976, Page(s): 598
| | PDF (264 KB)

A single-stage current amplifier permits 250 Mb/s modulation of a GaAs laser. The compensated 50 Â¿ bias input can be used to inject a 100 ps-risetime pulse, produced by a charged line generator with mercury-wetted reed relays and skin-effect compensated signal delay line. View full abstract»

• ### Class of majority-logic-decodable codes with a minimum distance of 4

Publication Year: 1976, Page(s):599 - 600
| | PDF (283 KB)

We prove that the (n = 4a2 + 4a + l, k = 4a2) binary code generated by 1+X2a+X2a+1+X4a+1 has a minimum distance of 4 and is 1-step majority-Iogic-decodable. View full abstract»

• ### Room-temperature 1.3 μm c.w. operation of a glass-clad Nd:y.a.g. single-crystal fibre laser end pumped with a single l.e.d.

Publication Year: 1976, Page(s):600 - 602
Cited by:  Papers (8)
| | PDF (403 KB)

Room-temperature c.w. laser action at 1.3 μm wavelength has been obtained using single-crystal glass-clad Nd:y.a.g. fibres end pumped with a single high-radiance l.e.d. The fibres were 0.5 cm long, 50 μm in diameter and had a cladding 3 μm thick. Threshold in a nonoptimum configuration was less than twice that at 1.06 μm. Application of a transparent, adherent glass... View full abstract»

• ### Cost-function minimisation in RC midseries ladder networks

Publication Year: 1976, Page(s):602 - 603
| | PDF (231 KB)

A complete class of transformed networks obtained by congruent transformation is given and necessary and sufficient conditions for the transformation matrix elements to give nonnegative values of the transformed network components are presented. The minimisation of the transformed network cost function is discussed. View full abstract»

• ### Comment on Electric-field control in planar Gunn-effect device with Schottky-barrier anode [and reply]

Publication Year: 1976, Page(s):603 - 604
| | PDF (162 KB)

First Page of the Article
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• ### Erratum: Dislocation-limited minority-carrier lifetime in n-type GaP

Publication Year: 1976
| | PDF (73 KB)

First Page of the Article
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## 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