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# Electronics Letters

## Filter Results

Displaying Results 1 - 25 of 34
• ### Determination of structural parameter variations in single-mode optical fibres by time-domain reflectometry

Publication Year: 1982, Page(s):489 - 490
Cited by:  Papers (7)
| | PDF (431 KB)

Backscatter measurements on single-mode fibres reveal apparent changes in local attenuation resulting from backscatter factor variations. The detailed shape of the backscatter waveforms is compared to known variations of fibre parameters. View full abstract»

• ### Low-loss fibre-coupled waveguide directional coupler modulator

Publication Year: 1982, Page(s):490 - 491
Cited by:  Papers (2)
| | PDF (465 KB)

We report a fibre-coupled Ti: LiNbO3 directional coupler modulator with total fibre-device-fibre insertion loss as low as 1.5 dB for Â¿=1.32 Â¿m. Low loss has been achieved by using diffusion parameters to give good mode match to the fibre and low propagation loss, an effective SiO2 buffer layer to eliminate electrode loading loss and a directional coupler geometry which minimises the effect of be... View full abstract»

• ### Six-port reflectometer circuit comprising three directional couplers

Publication Year: 1982, Page(s):491 - 493
Cited by:  Papers (7)
| | PDF (502 KB)

A six-port reflectometer circuit, assembled from three directional couplers and covering a waveguide passband, is described. Experimental results obtained from a WG 22 wave-guide version show that about 1 mW source power is sufficient for thermistor detectors to be used with the circuit, a level obtainable from millimeter-wave solid-state sources. View full abstract»

• ### Laser mode partition noise in optical wideband transmission links

Publication Year: 1982, Page(s):493 - 494
Cited by:  Papers (11)
| | PDF (384 KB)

Laser mode partition noise is an important source of noise in optical transmission systems operating with multimode lasers and dispersive fibres, e.g. single-mode fibres with non-zero material dispersion. The letter describes investigations which confirm the importance of considering laser mode partition noise when practical optical systems are projected. It also gives theoretical estimations and ... View full abstract»

• ### Observation of stimulated Brillouin scattering in low-loss silica fibre at 1.3 Â¿m

Publication Year: 1982, Page(s):495 - 496
Cited by:  Papers (32)
| | PDF (378 KB)

Stimulated Brillouin scattering (SBS) in low-loss single-mode silica fibre is observed at 1.32 Â¿m using a continuous-wave single-frequency Nd:YAG laser. The threshold for SBS is 5 mW and the transmitted power reaches a saturated maximum for launch powers exceeding about 10 mW. A conversion efficiency of 65% is observed. The Stokes frequency shift is 12.7Â±0.2 GHz. View full abstract»

• ### Remarks on system simplification under consideration of time responses

Publication Year: 1982, Page(s):496 - 497
Cited by:  Papers (5)
| | PDF (308 KB)

The letter highlights the significance of matching the terms of expansions around several points including s=0 and s=Â¿ in realising improved overall time-response approximation. View full abstract»

• ### Low-threshold oxide stripe GaAs/GaAlAs lasers grown by MOCVD

Publication Year: 1982, Page(s):497 - 499
| | PDF (525 KB)

MOCVD-grown insulator defined stripe GaAs/GaAlAs lasers with stripe widths of 6, 10, 20 and 150 Â¿m have been characterised. Uniform CW threshold currents as low as 45 mA, differential quantum efficiencies as high as 74%, and kink-free power levels as high as 20 mW/facet have been obtained in 160 Â¿m long, 6 Â¿m stripe lasers. The internal differential quantum efficiency measured from our 6 Â¿m st... View full abstract»

• ### New optical fibre fabrication method

Publication Year: 1982, Page(s):499 - 500
Cited by:  Papers (2)
| | PDF (338 KB)

A new method for optical fibre fabrication has been found. The method is based on the so-called sol-gel processÂ¿, which enables one to produce a core rod for optical fibre. Pure silica core fibre fabricated using this method exhibits an optical attenuation characteristic as low as 6 dB/km at a wavelength of 0.85 Â¿m. View full abstract»

• ### Two fast algorithms to compute the discrete receding horizon control gains

Publication Year: 1982, Page(s):500 - 501
| | PDF (300 KB)

Two fast algorithms are proposed to calculate the feedback gains of the receding horizon method to suboptimally control linear time-invariant multi-input, multi-output discrete systems. View full abstract»

• ### Output power saturation of BH laser under high current operation

Publication Year: 1982, Page(s):501 - 502
Cited by:  Papers (7)
| | PDF (289 KB)

Output power saturation of BH lasers under high current operation is analysed and it is concluded that such saturation is due to increase of leakage current through the burying layers. The mechanism of such leakage can be explained by a turn-on model of the bipolar transistor around the active region. View full abstract»

• ### z-plane analysis of networks of distributed and discrete systems

Publication Year: 1982, Page(s):502 - 504
| | PDF (372 KB)

A general electromagnetic transient analysis method is given for networks of distributed and discrete systems in any combination and interconnection. The principal properties of the method derive primarily from an initial equation-system formulation in the z-plane. View full abstract»

• ### Transient stimulated Brillouin scattering in long single-mode fibres

Publication Year: 1982, Page(s):504 - 506
Cited by:  Papers (15)
| | PDF (395 KB)

Recent experiments show that stimulated Brillouin scattering (SBS) in low-loss fibres could place a severe limitation on optical power levels for coherent optical transmission. The letter analyses the transient stimulated scattering produced when the laser is modulated, and it is concluded that the limitations due to SBS could be circumvented by using particular modulation techniques. View full abstract»

• ### Packet radio in a Rayleigh channel

Publication Year: 1982, Page(s):506 - 507
Cited by:  Papers (38)
| | PDF (264 KB)

Statistical multiple access is analysed for a number of independent transmitter-receiver pairs exchanging data packets over a shared mobile-radio channel. Rayleigh fading softensÂ¿ the channel, resulting in less packet contentions and higher traffic capacity than for the standard Aloha channel. View full abstract»

• ### CW room-temperature visible single quantum well Ga0.73Al0.27As diode lasers grown by metalorganic chemical vapour deposition

Publication Year: 1982, Page(s):507 - 509
Cited by:  Papers (1)
| | PDF (469 KB)

Room-temperature CW laser operation at 7125 Ã has been achieved in a (Ga1Â¿xAlxAs, xÂ¿0.27) single quantum well double heterostructure (SQW-DH) diode laser. The laser consists of a 9 Â¿m-wide delineated shallow proton stripe. The pulsed threshold current for a 250 Â¿m long device is 115 mA whereas the CW threshold current is 140 mA. The CW external differential quantum efficiency is 60%. View full abstract»

• ### Dielectric-waveguide filters using parallel-coupled grating resonators

Publication Year: 1982, Page(s):509 - 510
Cited by:  Papers (2)
| | PDF (332 KB)

Results for a new class of dielectric-waveguide bandpass filters are presented. The filters use pairs of gratings on a guide to make a resonator, and the resonators are coupled by side-by-side placement. Attenuation is by reflection around the passband and by absorption elsewhere. View full abstract»

• ### Speed power in planar two-dimensional electron gas FET DCFL circuit: a theoretical approach

Publication Year: 1982, Page(s):510 - 512
Cited by:  Papers (2)
| | PDF (463 KB)

A comparative study is made on the speed power of the two-dimensional electron gas FET (TEGFET) and the conventional GaAs FET. It is shown that the TEGFET is three times faster than the GaAs FET. Propagation delay times of 10 and 6 ps are predicted at 300 and 77 K, respectively, for a gate length of about 1 Â¿m. Effects of electron velocity and mobility are given. View full abstract»

• ### ZAP! Introducing the Zero-bias Avalanche Photodiode

Publication Year: 1982, Page(s):512 - 514
| | PDF (465 KB)

A novel heterostructure p-n junction diode is described which provides a photocurrent gain of 2 under zero external bias conditions. The necessary energy required to produce the additional electron-hole pair would be supplied by the internal electric field associated with the heterojunction energy gap difference. The ZAP diode structure has energy conversion applications as a photovoltaic detector... View full abstract»

• ### Special cases of Fliege's complementary transformation for active RC networks

Publication Year: 1982, Page(s):514 - 515
| | PDF (261 KB)

A transformation is given which consists of the application of Fliege's complementary transformation in a special way to a network of restricted topology. Since the transformation is a special case of Fliege's transformation, it does not alter the denominator of the network's voltage transfer ratio. However, whereas in Fliege's general transformation the numerator has to be determined by circuit a... View full abstract»

• ### Relationship between path length and attenuation of radio waves transmitted in a uniform rain-filled medium

Publication Year: 1982, Page(s):515 - 517
| | PDF (377 KB)

It has been accepted that rain attenuation (in an environment in which the rainfall rate is assumed uniform along the whole length of the radio link) is linear with respect to path length. It is shown here that for nonspherical raindrops this is not generally the case. Results over the frequency band 3Â¿30 GHz are presented. These demonstrate that, in certain circumstances, use of the path-length-... View full abstract»

• ### High-speed low-power DCFL using planar two-dimensional electron gas FET technology

Publication Year: 1982, Page(s):517 - 519
Cited by:  Papers (11)
| | PDF (445 KB)

Planar two-dimensional electron gas FETs (TEGFETs) have been shown to have ultra-high speed and low power in DCFL circuits operating at room temperature: 18.4 ps at 900 Â¿W and 32.5 ps at 62 Â¿W. The latter result and the simplicity of the process involved are compatible with VLSI requirements. View full abstract»

• ### Global convergence of Newton's method in the DC analysis of single-transistor networks

Publication Year: 1982, Page(s):519 - 520
Cited by:  Papers (1)
| | PDF (312 KB)

Global convergence of Newton's method is proved for the DC equations of a one-transistor network. Sufficient conditions are also given for global convergence in networks of n transistors. View full abstract»

• ### Mutual coupling between microstrip patch antennas

Publication Year: 1982, Page(s):520 - 522
Cited by:  Papers (14)
| | PDF (472 KB)

A theoretical approach to the mutual coupling phenomenon between microstrip patch antennas of arbitrary geometry and alignment is presented. The theory employs an equivalent magnetic wall model for each single radiator, a series expansion in resonant modes in connection with a reaction concept treatment of antenna interaction. Good agreement of theoretical and experimental data is observed in a wi... View full abstract»

• ### Intermittent fault coverage during test of electronic components and systems

Publication Year: 1982, Page(s):522 - 523
Cited by:  Papers (1)
| | PDF (298 KB)

Fault-detection experiments for electronic components and systems are usually designed for the detection of permanent or data-dependent faults. Treatment of intermittent faults in the literature has been restricted to the use of Markov models for the design of fault experiments capable of detecting intermittent faults having specified transition probabilities. In the letter a transformation has be... View full abstract»

• ### Experimental assessment of a 140 Mbit/s coherent optical receiver at 1.52 Â¿m

Publication Year: 1982, Page(s):523 - 525
Cited by:  Papers (6)
| | PDF (506 KB)

Homodyne detection has given a 10 dB improvement in receiver sensitivity over direct detection at a wavelength of 1.52 Â¿m and a data rate of 140 Mbit/s. This result was achieved with a local oscillator power of only Â¿32 dBm. View full abstract»

• ### Resistive multiport scattering matrix realisation using operational amplifiers

Publication Year: 1982, Page(s):525 - 527
| | PDF (419 KB)

A new structure realising the voltage-scattering matrix of resistive n-port networks using resistors and operational amplifiers is proposed. The effect of a finite gain-bandwidth product of operational amplifiers is discussed. 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