Your browser does not support JavaScript!
http://iet.metastore.ingenta.com
1887
banner image
image of Volume 23, Issue 6
Online ISSN 1350-911X Print ISSN 0013-5194

Electronics Letters

Volume 23, Issue 6, 12 March 1987

Volumes & issues:

Volume 23, Issue 6

12 March 1987

Complexity reduction in fully vector quantised stochastic coders
Design and realisation of high-gain 1.5 μm semiconductor TW optical amplifiers
  • Author(s): P. Brosson ; B. Fernier ; J. Benoit ; J.C. Simon ; B. Landousies
  • Source: Electronics Letters, Volume 23, Issue 6, p. 254 –256
  • DOI:  10.1049/el:19870186
  • Type: Article
  • + Show details - Hide details
  • p. 254 –256 (3)
    The influence of the waveguide parameters, leakage current, electrical and thermal resistances on the maximum linear gain and the corresponding tuning wavelength of buried-heterostructure (BH) semiconductor travelling-wave optical amplifiers (TWAs) operating around 1.5 μm is theoretically analysed. A 26 dB gain TWA has been designed and fabricated from a 400 μm-long BH laser with a 0.2 μm-thick active layer by using low-reflectivity SiO (R ≃ 6 × 10−4) coatings.
    Add to favourites
    Export citations
Transfer function matrix
Reduced-order models using optimal Laguerre approximations
DC and microwave characteristics of an In0.53Ga0.47As/In0.52Al0.48As modulation-doped quasi-MISFET
  • Author(s): K.S. Seo ; P.K. Bhattacharya ; K.R. Gleason
  • Source: Electronics Letters, Volume 23, Issue 6, p. 259 –260
  • DOI:  10.1049/el:19870189
  • Type: Article
  • + Show details - Hide details
  • p. 259 –260 (2)
    The DC and microwave performance of a modulation-doped InGaAs/InAlAs quasi-MISFET structure, grown by molecular beam epitaxy, is reported. Improved performance is obtained with the incorporation of Ti in the source-drain metallisation with which contact resistances as low as 0.1 Ωmm are measured. An extrinsic transconductance of 310mS/mm and a best value of fT=32 GHz in a 1.0 μ-gate device are measured at 300 K.
    Add to favourites
    Export citations
Soliton propagation in the presence of source chirping and mutual interaction in single-mode optical fibres
Content-addressable memories for storing and processing recursively subdivided images and trees
Interpretation of compact range measurements
Low-insertion-loss channel waveguides in LiNbO3 fabricated by proton exchange
Linear third-order discrete system stability under parameter variations
Novel microwave projection imaging for determination of internal structure
  • Author(s): K.I. Schultz  and  D.L. Jaggard
  • Source: Electronics Letters, Volume 23, Issue 6, p. 267 –269
  • DOI:  10.1049/el:19870195
  • Type: Article
  • + Show details - Hide details
  • p. 267 –269 (3)
    A novel microwave imaging technique based on the generalised weighted backprojection operator is introduced and tested using experimental data. Images of the internal structure of penetrable objects using this technique are compared and contrasted with images found from the classical back-projection method. It is demonstrated that the new method provides high-quality images of both discrete and continuous internal structure without the distortions characteristic of traditional methods.
    Add to favourites
    Export citations
Self: a self-timed systems design technique
Single-lobe ‘Y’ coupled laser diode arrays
Spectral attenuation measurement for fluoride glass single-mode fibres by Fourier transform techniques
  • Author(s): Y. Ohishi  and  S. Sakaguchi
  • Source: Electronics Letters, Volume 23, Issue 6, p. 272 –273
  • DOI:  10.1049/el:19870198
  • Type: Article
  • + Show details - Hide details
  • p. 272 –273 (2)
    A new spectral attenuation measurement system using a Fourier transform spectrometer is developed. The Fourier transform spectral attenuation measurement (FT-SAM) system makes the signal acquisition time for a wide wave-length range of 1.0–4.2μ much shorter than measurement with a conventional dispersive spectral attenuation measurement system. The spectral attenuation for a fluoride glass single-mode fibre, with a minimum loss of 3±1 dB/km at 2.5μm, is measured with this system.
    Add to favourites
    Export citations
Low-leakage InGaAs photodiodes grown on gaAs substrates using a graded strained-layer superlattice
General formalism for the study of nonlinear pulse propagation in optical fibres
Improved HF broadband wire antenna
Dielectric slab matched ferrite gyrator
  • Author(s): J. Uher ; F. Arndt ; J. Bornemann
  • Source: Electronics Letters, Volume 23, Issue 6, p. 278 –279
  • DOI:  10.1049/el:19870202
  • Type: Article
  • + Show details - Hide details
  • p. 278 –279 (2)
    A 180° nonreciprocal ferrite phase shifter with stepped dielectric impedance transformer sections at both ends is designed using the method of field expansion into eigenmodes. The rigorous optimisation method includes the higher-order mode interaction between the step discontinuities. The design achieves compact and simple components, as relatively thick, and consequently short, uniform ferrite slabs of standard dimensions may utilised. A computer-optimized design example provides about 180° ± 1° nonreciprocal differential phase shift between 12.2 and 12.8 GHz together with more than 24dB return loss.
    Add to favourites
    Export citations
Low-loss dispersion-shifted polarisation-maintaining fibres
Stress-relieved magnetoelastic amorphous metal DC magnetometer
Low-noise 8 GHz PIN/FET optical receiver
  • Author(s): J.L. Gimlett
  • Source: Electronics Letters, Volume 23, Issue 6, p. 281 –283
  • DOI:  10.1049/el:19870205
  • Type: Article
  • + Show details - Hide details
  • p. 281 –283 (3)
    An ultrawide-bandwidth, low-noise optical receiver has been designed for use in both multigigabit direct-detection or coherent heterodyne systems at 1.3 and 1.55 μm wavelengths. The receiver consists of a low-capacitance InGaAs PIN photodiode connected to a high-impedance three-stage GaAs FET preamplifier. Inductive peaking at the front end is used to reduce the receiver noise at high frequencies. The receiver has an equivalent input RMS noise current of < 12 pA/√Hz from 4 to 7 GHz. The measured 3 dB bandwidth of 8 GHz is the widest receiver bandwidth reported to date.
    Add to favourites
    Export citations
Measurement of flicker phase noise of 1.4 GHz MESFET amplifier at temperatures between 300 K and 1.26 K
  • Author(s): M.D. Hürlimann  and  W.N. Hardy
  • Source: Electronics Letters, Volume 23, Issue 6, p. 283 –284
  • DOI:  10.1049/el:19870206
  • Type: Article
  • + Show details - Hide details
  • p. 283 –284 (2)
    We have measured the phase noise of a low-noise 1.4GHz MESFET amplifier at temperatures between 300K and 1.26K and for sideband frequencies between 0.15 Hz and I kHz. In our experimental configuration the phase noise between 4.2 K and 2.17 K was large and mainly caused by bubbling of the liquid helium cryogen. However, the intrinsic phase noise, observed below 2.17 K, was lower than at room temperature, in contrast to earlier reported behaviour of amplifiers operated at X-band.
    Add to favourites
    Export citations
Fabrication and performance of an InP/InGaAsP monolithic 12 × 12-element matrixed LED array
  • Author(s): L.A. Koszi ; H. Temkin ; B.H. Chin ; S.G. Napholtz ; B.P. Segner
  • Source: Electronics Letters, Volume 23, Issue 6, p. 284 –286
  • DOI:  10.1049/el:19870207
  • Type: Article
  • + Show details - Hide details
  • p. 284 –286 (3)
    The fabrication of a large-area InP/InGaAsP double-heterostructure LED monolithic matrixed array of 144 light-emitting elements is presented. Each LED produces ˜2.5 mW at an operating current of 150mA with per-element bandwidths of ˜200 Mbit/s. The array, which we believe to be the largest integrated optoelectronic circuit fabricated in this material system, is thus capable of very high power output and bandwidth. Such arrays are expected to be useful in many optical data link applications.
    Add to favourites
    Export citations
Coherent lightwave transmission at 2 Gbit/s over 170 km of optical fibre using phase modulation
  • Author(s): A.H. Gnauck ; R.A. Linke ; B.L. Kasper ; K.J. Pollock ; K.C. Reichmann ; R. Valenzuela ; R.C. Alferness
  • Source: Electronics Letters, Volume 23, Issue 6, p. 286 –287
  • DOI:  10.1049/el:19870208
  • Type: Article
  • + Show details - Hide details
  • p. 286 –287 (2)
    We report coherent lightwave transmission at a data rate of 2Gbit/s over 170 km of optical fibre. Phase modulation is employed, and a bit error rate lower than 10-9 is achieved. The receiver sensitivity of –39.0 dBm 10-9 BER) is an improvement of 2.4 dB over the best previously published direct-detection result for non-return-to-zero transmission.
    Add to favourites
    Export citations
Low-temperature process for high-mobility polysilicon TFTs
Optical sampling with gain-switched, pulse-compressed, distributed feedback laser diodes
  • Author(s): D.L. Franzen ; Y. Yamabayashi ; T. Kanada
  • Source: Electronics Letters, Volume 23, Issue 6, p. 289 –290
  • DOI:  10.1049/el:19870210
  • Type: Article
  • + Show details - Hide details
  • p. 289 –290 (2)
    Chirped pulses from gain-switched, distributed feedback laser diodes at a wavelength of 1.3μm are compressed to 8.7ps. FWHM by the linear dispersion properties of single-mode fibre. These pulses are used to optically sample fast waveforms from other 1.3 pm laser diodes. The high time resolution sampling system uses a fibre coupler to combine beams; this eliminates critical alignment and results in a practical design.
    Add to favourites
    Export citations
Endless polarisation control using four fibre squeezers
Serial-data computation on twin pipelines
Computer simulation of an induction heating power supply using power MOSFETs
InP/GaInAs heterojunction bipolar transistors with improved electrical characteristics grown on strained buffer layers
100 Mbit/s PSK heterodyne experiment using a travelling-wave laser amplifier
High-transconductance AlInAs/GaInAs HIFETs grown by MOCVD
Wavelength dependence of optical oxidation of silicon
20 GHz dynamic frequency divider with GaAs advanced SAINT and air-bridge technology
Refractive waveguide lenses: a new design
Highly efficient InGaAs/InAIAs MQW waveguide phase shifter
  • Author(s): K. Wakita ; Y. Yoshikuni ; Y. Kawamura
  • Source: Electronics Letters, Volume 23, Issue 6, p. 303 –304
  • DOI:  10.1049/el:19870220
  • Type: Article
  • + Show details - Hide details
  • p. 303 –304 (2)
    Characteristics of an optical waveguide phase shifter that uses field-induced variation of the refractive index change in reverse-biased PIN InGaAs/InAlAs multiple quantum wells (MQWs) are reported for the first time. High mesa waveguides are fabricated by molecular beam epitaxy and wet chemical etching. The largest phase-shifting efficiency (66° / V mm) ever reported in a reverse-biased structure operating at long wavelengths is obtained near the bandgap; however, this is located in a low absorption wavelength region.
    Add to favourites
    Export citations
High carrier rejection for a 3.7 to 4.2 GHz BPSK modulator
Erratum: Polarisation fluctuation in optical-fibre submarine cable under 8000 m deep sea environmental conditions
Erratum: Analysis of singular systems using Taylor series approach
Erratum: Taylor series approach to functional approximation for inversion of Laplace transforms
Erratum: Coupled mode analysis of wavefront properties of phased array diode lasers
Erratum: New analysis of LED to single-mode fibre coupling
Erratum: Compact broadband microstrip antenna
Erratum: Convolutional coding for BPSK system with orthogonal sounding tone on fast Rayleigh fading channel

Most viewed content for this Journal

Article
content/journals/el
Journal
5
Loading

Most cited content for this Journal

Print this page
This is a required field
Please enter a valid email address