Your browser does not support JavaScript!
http://iet.metastore.ingenta.com
1887
banner image
image of Volume 18, Issue 21
Online ISSN 1350-911X Print ISSN 0013-5194

Electronics Letters

Volume 18, Issue 21, 14 October 1982

Volumes & issues:

Volume 18, Issue 21

14 October 1982

Transmission experiments through 101 km and 84 km of single-mode fibre at 274 Mbit/s and 420 Mbit/s
  • Author(s): M.M. Boenke ; R.E. Wagner ; D.J. Will
  • Source: Electronics Letters, Volume 18, Issue 21, p. 897 –898
  • DOI:  10.1049/el:19820611
  • Type: Article
  • + Show details - Hide details
  • p. 897 –898 (2)
    Four transmission experiments through low-loss single-mode optical fibre at 1.3 μm have been performed at 274 Mbit/s and 420 Mbit/s with different objectives. The first demonstrates transmission through 101 km of single-mode fibre at 274 Mbit/s with negligible dispersion penalty. The second experiment at 274 Mbit/s and 84 km uses only components suitable for use in an undersea cable system. Two additional experiments, both at 420 Mbit/s, accomplish a bitrate × distance product of 35 GHzkm with 84 km of fibre and show no dispersion penalty with 63 km and 2.4 ps/km nm dispersion.
    Add to favourites
    Export citations
Compact and rugged all-fibre coupler for wavelength division multiplexing
Implementation of digital signatures
Generation of single-longitudinal-mode subnanosecond light pulses by high-speed current modulation of monolithic two-section semiconductor lasers
  • Author(s): K.J. Ebeling ; L.A. Coldren ; B.I. Miller ; J.A. Rentschler
  • Source: Electronics Letters, Volume 18, Issue 21, p. 901 –902
  • DOI:  10.1049/el:19820614
  • Type: Article
  • + Show details - Hide details
  • p. 901 –902 (2)
    The spectral behaviour of monolithic two-section GaInAsP/InP lasers is studied. Single-longitudinal-mode light pulses of less than 750 ps length are produced by driving the long section of the laser only or by prebiasing the long cavity and modulating the short section with a current pulse of 1 ns halfwidth. The wavelength of the output light can be changed by varying the operation temperature or the prebias level.
    Add to favourites
    Export citations
Measurement of beam parameters of index-guided and gain-guided single-frequency InGaAsP injection lasers
Observation of transient spectra and mode partition noise of injection lasers
Fast decipherment algorithm for RSA public-key cryptosystem
Measurement of polarisation mode dispersion in elliptical-core single-mode fibres at 1.3 μm
Low field mobility, effective saturation velocity and performance of submicron GaAs MESFETs
  • Author(s): M.S. Shur
  • Source: Electronics Letters, Volume 18, Issue 21, p. 909 –910
  • DOI:  10.1049/el:19820619
  • Type: Article
  • + Show details - Hide details
  • p. 909 –910 (2)
    An analytical model is proposed which relates the transconductance of submicron GaAs MESFETs to a low field mobility, effective electron saturation velocity and device geometry and doping. The model predicts that the effective saturation velocity determines the performance of the devices at relatively high pinch-off voltages (Vpo > 5 V). At smaller pinch-off voltages (especially for enhancement-mode devices) the low field mobility becomes increasingly important, leading to additional advantages of GaAs devices over Si devices. Another prediction is a higher transconductance in thinner and higher-doped devices. This effect is also more important for devices with low pinch-off voltages. The obtained results may be used to deduce the effective values of the electron drift velocity in GaAs MESFETs as a function of the gate length.
    Add to favourites
    Export citations
How iterative transformations can help to crack the Merkle-Hellman cryptographic scheme
Single-mode optical-fibre index profiling with improved resolution
Radio propagation within buildings at 900 MHz
Simple low-cost correlator and multiplier circuits
Fluctuations on OTS-Earth copolar link against diurnal and seasonal variations
  • Author(s): A. Vander Vorst ; D. Vanhoenacker ; L. Mercier
  • Source: Electronics Letters, Volume 18, Issue 21, p. 915 –917
  • DOI:  10.1049/el:19820624
  • Type: Article
  • + Show details - Hide details
  • p. 915 –917 (3)
    Measurements on the copolar level of the 11.575 GHz OTS-Earth link have been analysed during the year 1981, using a 1 s sampling time. The variation of the fluctuations amplitude is evaluated as a function of the time of day and of the month of the year. It is compared to the number of attenuation events over the same period and against the same parameters. The statistic of the number of occurrences is calculated as a function of the amplitude of the events.
    Add to favourites
    Export citations
Theoretical random process for prediction of rain attenuation statistics in site diversity satellite links above 10 GHz
  • Author(s): C. Capsoni  and  E. Matricciani
  • Source: Electronics Letters, Volume 18, Issue 21, p. 917 –919
  • DOI:  10.1049/el:19820625
  • Type: Article
  • + Show details - Hide details
  • p. 917 –919 (3)
    Site diversity systems are foreseen for earth-to-satellite links in localities with high rain-induced attenuation operating at frequencies above 10 GHz. An analytical model for the rain-rate statistical process is developed using radar-derived information on the rain structure collected at Spino d'Adda in the framework of the Sirio experiment. The procedure for estimating rain attenuation in both single and site diversity systems is outlined in a general formulation which makes it applicable to different situations. The model gives results very similar to experimental ones.
    Add to favourites
    Export citations
Influence of pressure on temperature sensitivity of GaxIn1−xAsyP1−y lasers
Quantum mechanical explanation of spontaneous emission K-factor
  • Author(s): D. Marcuse
  • Source: Electronics Letters, Volume 18, Issue 21, p. 920 –922
  • DOI:  10.1049/el:19820627
  • Type: Article
  • + Show details - Hide details
  • p. 920 –922 (3)
    The rate of spontaneous photon emission in an injection laser depends on whether the laser modes are gain-guided or index-guided. For gain-guided modes the ratio of spontaneous to stimulated emission is greater by a factor K to the corresponding ratio for index-guided modes. Recently, the validity of the K-factor was questioned by means of a quantum mechanical argument. It is the purpose of this letter to show that quantum theory does not contradict the classical derivation of the K-factor but instead confirms its validity and sheds new light on the physics of spontaneous emission into gain-guided laser modes.
    Add to favourites
    Export citations
Limit cycles in relay systems
Resolution of monochromatic signal sources using a simple receiving antenna array
Ground station antenna crosspolarisation measurements with an imperfectly polarised ancillary antenna
  • Author(s): K.M. Keen
  • Source: Electronics Letters, Volume 18, Issue 21, p. 924 –926
  • DOI:  10.1049/el:19820630
  • Type: Article
  • + Show details - Hide details
  • p. 924 –926 (3)
    A technique has been described for measuring the crosspolarisation radiation patterns of linearly polarised, frequency reuse satellite ground station antennas, using a satellite as the remote source. This involves sampling of the imperfect satellite wave with a high polarisation purity ancillary antenna, and the application of a correction factor to the measured crosspolarisation levels. In practice, the ancillary antenna may have a small but finite crosspolarisation level, and error levels due to this are of interest. Error level expressions are given here, and some typical results are considered.
    Add to favourites
    Export citations
Cascaded bandpass vth-law devices
  • Author(s): A.K. Gupta ; W.B. Garner ; E.J. Baghdady
  • Source: Electronics Letters, Volume 18, Issue 21, p. 926 –927
  • DOI:  10.1049/el:19820631
  • Type: Article
  • + Show details - Hide details
  • p. 926 –927 (2)
    The effect of the n-cascaded bandpass vth-law devices on the sum of a strong signal and a weak signal is analysed. It is shown that if any of the nonlinear devices is a hard-limiter, the n-cascaded nonlinearities have the same effect as that of a single hard-limiter. If two such cascaded nvth-law devices (differing in at least one vth-value) or two complex bandpass nonlinearities are connected in parallel, we obtain the generalised form of a ‘power-division’ multiplex system which utilises a feed-forward across a limiter technique.
    Add to favourites
    Export citations
Residue number system error checking using expanded projection
  • Author(s): W.K. Jenkins
  • Source: Electronics Letters, Volume 18, Issue 21, p. 927 –928
  • DOI:  10.1049/el:19820632
  • Type: Article
  • + Show details - Hide details
  • p. 927 –928 (2)
    A new concept called expanded projection is presented that simplifies the process of error detection and location in redundant residue number codes. Expanded projection simplifies the circuit complexity of the error checker, resulting in a structure which is potentially useful for VLSI implementation. It is expected that simplified designs for the error checker will result in more practical applications of residue number arithmetic to achieve fault tolerant performance in special-purpose digital processors.
    Add to favourites
    Export citations
1.5 μm optical heterodyne system operating over 30 km of monomode fibre
DICMOS—novel MOS logic
  • Author(s): B.J. Hosticka ; U. Kleine ; H. Vogt ; G. Zimmer
  • Source: Electronics Letters, Volume 18, Issue 21, p. 930 –932
  • DOI:  10.1049/el:19820634
  • Type: Article
  • + Show details - Hide details
  • p. 930 –932 (3)
    A novel dynamic ratioless logic called DICMOS is proposed. The main features are low power dissipation and high packing density. No quiescent power is consumed. The realisation of a logic function requires only one MOS transistor per input variable and only one additional pull-up device; e.g. the pull-up element could be implemented as a Schottky-barrier diode, i.e. a simple contact.
    Add to favourites
    Export citations
Dielectric guiding due to an inverted gain profile in GaAs/GaAlAs lasers
Selected-area molecular beam epitaxy on ion-implanted GaAs substrates
Erratum: Floating voltage-controlled resistors in CMOS technology
Erratum: Reply to Comment on ‘Fundamental mode spot-size measurement in single-mode optical fibres’
Erratum: Phototransistors in digital optical communications systems for 1–1.6 μm wavelength
Erratum: Finite-element analysis of flat overlay waveguides for acoustic surface waves using acoustic surface impedance
Erratum: Turn-on delay for Josephson logic devices with high damping
Erratum: Parasitic insensitive toggle-switched capacitor and its applications to switched-capacitor networks

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