Online ISSN
1350-911X
Print ISSN
0013-5194
Electronics Letters
Volume 20, Issue 15, 19 July 1984
Volumes & issues:
-
Volume 59 (2023)
-
Volume 58 (2022)
-
Volume 57 (2021)
-
Volume 56 (2020)
-
Volume 55 (2019)
-
Volume 54 (2018)
-
Volume 53 (2017)
-
Volume 52 (2016)
-
Volume 51 (2015)
-
Volume 50 (2014)
-
Volume 49 (2013)
-
Volume 48 (2012)
-
Volume 47 (2011)
-
Volume 46 (2010)
-
Volume 45 (2009)
-
Volume 44 (2008)
-
Volume 43 (2007)
-
Volume 42 (2006)
-
Volume 41 (2005)
-
Volume 40 (2004)
-
Volume 39 (2003)
-
Volume 38 (2002)
-
Volume 37 (2001)
-
Volume 36 (2000)
-
Volume 35 (1999)
-
Volume 34 (1998)
-
Volume 33 (1997)
-
Volume 32 (1996)
-
Volume 31 (1995)
-
Volume 30 (1994)
-
Volume 29 (1993)
-
Volume 28 (1992)
-
Volume 27 (1991)
-
Volume 26 (1990)
-
Volume 25 (1989)
-
Volume 24 (1988)
-
Volume 23 (1987)
-
Volume 22 (1986)
-
Volume 21 (1985)
-
Volume 20 (1984)
-
Volume 19 (1983)
-
Volume 18 (1982)
-
Volume 17 (1981)
-
Volume 16 (1980)
-
Volume 15 (1979)
-
Volume 14 (1978)
-
Volume 13 (1977)
-
Volume 12 (1976)
-
Volume 11 (1975)
-
Volume 10 (1974)
-
Volume 9 (1973)
-
Volume 8 (1972)
-
Volume 7 (1971)
-
Volume 6 (1970)
-
Volume 5 (1969)
-
Volume 4 (1968)
-
Volume 3 (1967)
-
Volume 2 (1966)
-
Volume 1 (1965)
Volume 20, Issue 15
19 July 1984
Tunable single-mode excitation in multimode fibres
- Author(s): P. Facq ; F. de Fornel ; F. Jean
- Source: Electronics Letters, Volume 20, Issue 15, p. 613 –614
- DOI: 10.1049/el:19840422
- Type: Article
- + Show details - Hide details
-
p.
613
–614
(2)
Mode selection in lasers is used in order to provide high-purity easy-to-implement single-mode launching in optical fibres. Mode-to-mode switching automatically maintains centring, scaling and alignment. Application of the principle to selective launching into a weakly multimode fibre (V=4) is demonstrated.
Resonant frequency of a tunable rectangular patch antenna
- Author(s): D.L. Sengupta
- Source: Electronics Letters, Volume 20, Issue 15, p. 614 –615
- DOI: 10.1049/el:19840423
- Type: Article
- + Show details - Hide details
-
p.
614
–615
(2)
The uniform transmission-line model is applied to determine the resonant frequency of a coaxial probe fed rectangular patch antenna tuned by a number of passive metallic posts suitably placed within the antenna's boundary. An approximate expression is given for the resonant frequency as a function of the post location and number, and of the other characteristic parameters of the antenna. Theoretical results are compared with available measured values.
Optimisation of modulation-doped heterostructures for TEGFET operation at room temperature
- Author(s): H. Dämbkes ; W. Brockerhoff ; K. Heime ; K. Ploog ; G. Weimann ; W. Schlapp
- Source: Electronics Letters, Volume 20, Issue 15, p. 615 –617
- DOI: 10.1049/el:19840424
- Type: Article
- + Show details - Hide details
-
p.
615
–617
(3)
Optimisation of selectively doped (AlGa)As/GaAs heterostructures for TEGFET applications at room temperature is reported. The introduction of a thick (>0.1 μm) highly doped GaAs top layer considerably reduces parasitic resistances and improves device performance. Best results for 1.4 μm gate length at room temperature are: transconductance 220 mS/mm; source resistance 0.2–0.4 mm; contact resistance less than 0.1 Ω mm and cutoff frequency 25 GHz. Results from comparable structures without a thick top layer are inferior by about 25%.
Gigabit per second operation by monolithically integrated InGaAsP/InP LD-FET
- Author(s): K. Kasahara ; J. Hayashi ; H. Nomura
- Source: Electronics Letters, Volume 20, Issue 15, p. 618 –619
- DOI: 10.1049/el:19840425
- Type: Article
- + Show details - Hide details
-
p.
618
–619
(2)
A single-step grown 1.3 μm buried-heterostructure laser and FET are monolithically integrated on a semi-insulating InP substrate. 2 Gbit/s RZ random pulse modulation has been first achieved for monolithic light sources.
Dual digital transmission system for multipair cables based on “crank-shaft coding”
- Author(s): P.J. Van Gerwen ; W.A.M. Snijders ; N.A.M. Verhoeckx
- Source: Electronics Letters, Volume 20, Issue 15, p. 619 –621
- DOI: 10.1049/el:19840426
- Type: Article
- + Show details - Hide details
-
p.
619
–621
(3)
A transmission system which provides two virtually independent digital channels for digital voice or data on a single two-wire connection is described. The basis of this system is the proposed “crank-shaft code”. Full-duplex operation can be obtained in a straightforward way by including echo cancellation.
Experimental investigation of the beam spot size radius in single-mode fibre tapers
- Author(s): R. Keil ; E. Klement ; K. Mathyssek ; J. Wittmann
- Source: Electronics Letters, Volume 20, Issue 15, p. 621 –622
- DOI: 10.1049/el:19840427
- Type: Article
- + Show details - Hide details
-
p.
621
–622
(2)
Fibre tapers have been evaluated with regard to the spot size radius enlargement effect predicted theoretically. The experiments show that the expected amount of improvement does not occur under the applied drawing conditions. For fibre tapers with taper lengths up to 1 mm and fibre core inclination angles between 0.6 and 1.2° it amounts to 20% at maximum.
Effective recombination velocity of polysilicon contacts for bipolar transistors
- Author(s): G.W. Bakker ; D.J. Roulston ; A.A. Eltoukhy
- Source: Electronics Letters, Volume 20, Issue 15, p. 622 –624
- DOI: 10.1049/el:19840428
- Type: Article
- + Show details - Hide details
-
p.
622
–624
(3)
The effective surface recombination velocity is determined analytically for a doped polysilicon contact to the emitter of a bipolar transistor in the presence of a thin interfacial oxide layer. Results are presented for various doping levels, oxide thicknesses and barrier heights. The analysis considers both tunnelling and thermionic emission through the interface.
InGaAsP 1.3 μm optical amplifier-modulator integrated with a fibre-resonator mode-locked laser
- Author(s): G. Eisenstein ; R.S. Tucker ; I.P. Kaminow ; T.P. Lee ; C.A. Burrus
- Source: Electronics Letters, Volume 20, Issue 15, p. 624 –625
- DOI: 10.1049/el:19840429
- Type: Article
- + Show details - Hide details
-
p.
624
–625
(2)
An InGaAsP 1.3 μm amplifier-modulator integrated with a laser which is mode locked in a fibre resonator is demonstrated. Transform limited pulses with 25 ps duration were gated by the amplifier-modulator at a bit rate of 1.05 Gbit/s with an on/off ratio of 20 dB.
Amplifier-modulator integrated with a cleaved-coupled-cavity injection laser
- Author(s): T.P. Lee ; C.A. Burrus ; G. Eisenstein ; W.B. Sessa ; P. Besomi
- Source: Electronics Letters, Volume 20, Issue 15, p. 625 –627
- DOI: 10.1049/el:19840430
- Type: Article
- + Show details - Hide details
-
p.
625
–627
(3)
We have demonstrated an external amplifier-modulator integrated with a cleaved-coupled-cavity injection laser on the same 1.3 μm InGaAsP/InP laser chip. The maximum available gain was 20 at an input power of −19.2 dBm, and it reduced to 10 at an input power of −10.5 dBm. High on/off extinction ratios and side-mode suppression >100:1 were achieved at about 1 Gbit/s (NRZ) modulation rate.
Integrated VIS SC filter with lattice reference structure
- Author(s): D. Brückmann and U. Kleine
- Source: Electronics Letters, Volume 20, Issue 15, p. 627 –628
- DOI: 10.1049/el:19840431
- Type: Article
- + Show details - Hide details
-
p.
627
–628
(2)
Symmetric VIS SC filters simulating reference filters in classical lattice configuration can be realised with less hardware. A fifth-order PCM lowpass with only three operational amplifiers has been designed and integrated in standard CMOS Si-gate technology. VIS SC lattice filters show excellent passband-sensitivity properties. Owing to the higher stopband sensitivity with respect to element tolerances, stopband attenuation requirements in excess of about 35–40 dB can be satisfied only by cascading lower-order SC lattice filters.
Integrated bipolar master/slave D-flip-flop with multiplexing capability for Gbit/s operation
- Author(s): R.H. Derksen ; H.-M. Rein ; J. Vathke
- Source: Electronics Letters, Volume 20, Issue 15, p. 628 –630
- DOI: 10.1049/el:19840432
- Type: Article
- + Show details - Hide details
-
p.
628
–630
(3)
A versatile integrated bipolar circuit developed for a broadband communication system is described. It consists of a master/slave D-flip-flop with a 2:1 time-division multiplexer at the input and a powerful buffer stage at the output. Despite realisation in a relatively simple bipolar technology, bit rates up to 1.5 Gbit/s (NRZ) were measured.
Scheme for detection of subcarrier modulated optical signals using switched parametric amplification
- Author(s): S. Rakshit ; N.B. Chakraborti ; R. Sarin
- Source: Electronics Letters, Volume 20, Issue 15, p. 630 –631
- DOI: 10.1049/el:19840433
- Type: Article
- + Show details - Hide details
-
p.
630
–631
(2)
Switched parametric amplification is used to amplify detected subcarrier modulated fibre-opt)c signals. A large gain of the order of 23 dB has been easily obtained, and the distortion is found to be below 25 dB over an input signal range of 20 dB.
Effect of laser chirp on optical systems—initial tests using a 1480 nm DFB laser
- Author(s): D.A. Frisch and D.A. Henning
- Source: Electronics Letters, Volume 20, Issue 15, p. 631 –632
- DOI: 10.1049/el:19840434
- Type: Article
- + Show details - Hide details
-
p.
631
–632
(2)
Initial assessment of the effect of laser “chirp” on optical systems is described. Measurements of the wavelength shift and its effect on the received pulse after 4 km and 80 km of dispersive fibre are presented. The results are in good agreement with simple modelling, which predicts no penalty for this system Further tests are needed to determine whether this behaviour is typical.
Double-polarisation radar measurements
- Author(s): M. Gherardelli ; D. Giuli ; M. Fossi
- Source: Electronics Letters, Volume 20, Issue 15, p. 633 –634
- DOI: 10.1049/el:19840435
- Type: Article
- + Show details - Hide details
-
p.
633
–634
(2)
This letter shows some experimental results obtained with a double-polarisation S-band radar using fixed circular polarisation at transmit and two orthogonal circularly polarised channels at receipt. The results refer to the short-time polarisation behaviour of aircraft target and ground clutter. From these results it can be inferred that adaptative polarisation techniques can be effective in improving the signal/clutter ratio.
Electroabsorption in InGaAsP-InP double heterostructures
- Author(s): N.K. Dutta and N.A. Olsson
- Source: Electronics Letters, Volume 20, Issue 15, p. 634 –635
- DOI: 10.1049/el:19840436
- Type: Article
- + Show details - Hide details
-
p.
634
–635
(2)
This letter reports the measurements of electroabsorption in InGaAsP-InP double heterostructures for electric fields in the range of 10–300 kV/cm. The absorption of the waveguide modes is very large (-40 cm−1 cm at−5 V applied bias) for photon energies ~;100 meV from the bandgap The electro-absorption is polarisation dependent. The absorption for light polarised along the field (TM-mode) is larger than that for light polarised normal to the field (TE-mode). The electroabsorption effect can be used to produce light amplitude modulators, polarisers and photodetectors.
Low-dark-current low-voltage 1.3–1.6 μm avalanche photodiode with high-low electric field profile and separate absorption and multiplication regions by molecular beam epitaxy
- Author(s): F. Capasso ; A.Y. Cho ; P.W. Foy
- Source: Electronics Letters, Volume 20, Issue 15, p. 635 –637
- DOI: 10.1049/el:19840437
- Type: Article
- + Show details - Hide details
-
p.
635
–637
(3)
The operation of the recently disclosed heterojunction avalanche photodiode with high-low electric field profile and separate absorption and multiplication regions (HI-LO SAM APD) is demonstrated. This new structure which features a doping spike in the wide gap layer offers several advantages over conventional SAM APDs (lower dark current and excess noise factor, greater gain stability). Low dark currents (≃1 nA), low voltage operation (−26 V) and gains as high as 50 at 1.60 μm are demonstrated in an Al0.48In0.52As/Ga0 47In0 53As prototype grown by molecular beam epitaxy.
Simplified Green's function for SAW generation which allows for the LSW
- Author(s): F. Huang
- Source: Electronics Letters, Volume 20, Issue 15, p. 637 –638
- DOI: 10.1049/el:19840438
- Type: Article
- + Show details - Hide details
-
p.
637
–638
(2)
An approximation for the Green's function used to analyse surface-acoustic-wave generation on piezoelectrics is proposed. It allows for the effect of the leaky surface wave. The result is useful for calculating the reflectivity of, and velocity change due to, thin metal dots on Y-cut LiNbO3.
Single error correcting and multiple unidirectional error detecting cyclic an arithmetic codes
- Author(s): N. Gaitanis
- Source: Electronics Letters, Volume 20, Issue 15, p. 638 –640
- DOI: 10.1049/el:19840439
- Type: Article
- + Show details - Hide details
-
p.
638
–640
(3)
We present cyclic AN arithmetic codes capable of single error correction and multiple unidirectional error detection. These codes can be used throughout a fault-tolerant computer, and they eliminate the need for encoding/decoding circuits and code translation circuits. We use criteria for the determination of the unidirectional error detection capability for a given AN code, and we present a new error correction/detection scheme.
Generation of 4 ps light pulses from directly modulated V-groove lasers
- Author(s): D. Bimberg ; K. Ketterer ; H.E. Schöll ; H.P. Vollmer
- Source: Electronics Letters, Volume 20, Issue 15, p. 640 –641
- DOI: 10.1049/el:19840440
- Type: Article
- + Show details - Hide details
-
p.
640
–641
(2)
4 ps light pulses at repetition rates up to 10 MHz with an output power of some milliwatts are generated at 840 nm by directly modulating commercial GaAlAs V-groove lasers by specially designed avalanche generators. The pulses are measured using an ultrafast streak camera and present the fastest light pulses obtained until now by direct modulation of a semiconductor laser. The avalanche generators produce pulses of 125–200 ps FWHM with voltages up to 25 and 38 V, respectively.
Most viewed content for this Journal
Article
content/journals/el
Journal
5
Most cited content for this Journal
-
Extreme multistability in a memristive circuit
- Author(s): Bo-Cheng Bao ; Quan Xu ; Han Bao ; Mo Chen
- Type: Article
-
Absorptive frequency selective surface using parallel LC resonance
- Author(s): Qiang Chen ; Liguo Liu ; Liang Chen ; Jiajun Bai ; Yunqi Fu
- Type: Article
-
Partial spectral search-based DOA estimation method for co-prime linear arrays
- Author(s): Fenggang Sun ; Peng Lan ; Bin Gao
- Type: Article
-
Experimental verification of on-chip CMOS fractional-order capacitor emulators
- Author(s): G. Tsirimokou ; C. Psychalinos ; A.S. Elwakil ; K.N. Salama
- Type: Article
-
54 Gbit/s OOK transmission using single-mode VCSEL up to 2.2 km MMF
- Author(s): G. Stepniak ; A. Lewandowski ; J.R. Kropp ; N.N. Ledentsov ; V.A. Shchukin ; N. Ledentsov Jr. ; G. Schaefer ; M. Agustin ; J.P. Turkiewicz
- Type: Article
