Online ISSN
1350-911X
Print ISSN
0013-5194
Electronics Letters
Volume 25, Issue 13, 22 June 1989
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 25, Issue 13
22 June 1989
Fast algorithm for calculating alphabet-constrained rate-distortion functions
- Author(s): W.T. Penzhorn and G.J. Kühn
- Source: Electronics Letters, Volume 25, Issue 13, p. 809 –810
- DOI: 10.1049/el:19890544
- Type: Article
- + Show details - Hide details
-
p.
809
–810
(2)
A new algorithm is presented for the calculation of ratedistortion functions for which the reproduction alphabet has been constrained to a finite size with its reproduction symbols occurring with fixed probability. The algorithm can be used to calculate reproduction alphabets for a trellis coded quantiser for the encoding of analogue information sources.
30 Hz-linewidth, diode laser-pumped, Nd:GGG nonplanar ring oscillators by active frequency stabilisation
- Author(s): T. Day ; A.C. Nilsson ; M.M. Fejer ; A.D. Farinas ; E.K. Gustafson ; C.D. Nabors ; R.L. Byer
- Source: Electronics Letters, Volume 25, Issue 13, p. 810 –812
- DOI: 10.1049/el:19890545
- Type: Article
- + Show details - Hide details
-
p.
810
–812
(3)
We report a heterodyne linewidth of less than 30 Hz for the beatnote between the outputs of two 282 THz (1.062µm) Nd:GGG nonplanar ring oscillators (NPROs). The lasers were independently locked to adjacent axial modes of a highfinesse interferometer. The remnant frequency noise appears to be dominated by free spectral range fluctuations in the reference interferometer rather than by residual laser noise.
Improved radiation hardness of MOS devices with ultrathin nitrided oxide gate dielectrics prepared by rapid thermal processing
- Author(s): G.Q. Lo ; D.K. Shih ; W.C. Ting ; D.L. Kwong
- Source: Electronics Letters, Volume 25, Issue 13, p. 812 –813
- DOI: 10.1049/el:19890546
- Type: Article
- + Show details - Hide details
-
p.
812
–813
(2)
The radiation hardness of MOS devices with ultrathin nitrided oxides (~100A) prepared by rapid thermal nitridation (RTN) of thin oxides has been studied. The radiation was performed by exposing devices under X-rays of 50 keV to a dose of 0.5 Mrad(Si). Compared with conventional thermal oxides, the RTN oxide devices exhibit a much smaller increase in both the fixed charge Nf and the interface state Dit densities. In addition, it is found that higher RTN temperature and/or longer durations produce smaller ΔNf and ΔDit.
Stationary charge domain in GaAs MESFETs: dimensional and electrical characterisation
- Author(s): L.C. Kretly and A.J. Giarola
- Source: Electronics Letters, Volume 25, Issue 13, p. 813 –814
- DOI: 10.1049/el:19890547
- Type: Article
- + Show details - Hide details
-
p.
813
–814
(2)
Numerical results of the location, size and voltage associated with stationary dipole charge layers in GaAs MESFETs and their dependences on gate and drain bias are presented. The results suggest the need of more analytical work describing the domain characteristics for a better understanding of how the dipole charge layer influences GaAs MESFET operation.
Frequency stabilisation of λ/4-shifted DFB laser to stabilised optical resonator
- Author(s): S. Matsumoto and M. Fujise
- Source: Electronics Letters, Volume 25, Issue 13, p. 814 –816
- DOI: 10.1049/el:19890548
- Type: Article
- + Show details - Hide details
-
p.
814
–816
(3)
The frequency of a 1.55µm-range GaInAsP λ/4-shifted DFB laser is locked to the resonant frequencies of a confocal etalon of which the mirror spacing is stabilised with a frequency-stabilised HeNe laser. An Allan variance of less than 10-11 was achieved for averaging times longer than 1 s without frequency modulation of the laser diode.
Digital realisation of forward and inverse models of electromagnetic scattering
- Author(s): P.R. Smith
- Source: Electronics Letters, Volume 25, Issue 13, p. 816 –817
- DOI: 10.1049/el:19890549
- Type: Article
- + Show details - Hide details
-
p.
816
–817
(2)
A recent geometrical treatment of forward and inverse scattering problems, posed by electromagnetic waves illuminating a one-dimensional dielectric inhomogeneity, is interpreted within the framework of digital signal analysis. Quantitative inverse solutions are described, and are illustrated by an example in the context of real-time nondestructive evaluation.
Demonstration of novel optical multichannel grating demultiplexer receiver (MGD) for HDWDM systems
- Author(s): Y. Kanabar and N. Baker
- Source: Electronics Letters, Volume 25, Issue 13, p. 817 –819
- DOI: 10.1049/el:19890550
- Type: Article
- + Show details - Hide details
-
p.
817
–819
(3)
A novel implementation of a multichannel grating demultiplexer receiver suitable for HDWDM applications is described. The prototype receiver, capable of 10-channel operation spaced at 4nm, uses a 16-element GalnAs/InP monolithic linear photodetector array and silicon preamplifier ICs. The sensitivity at the input to the demultiplexer is – 3 1 dBm at 200Mbit/s. Optical and electrical crosstalk measurements in the receiver are presented, and limited tests have shown that there is a negligible crosstalk penalty.
High-power grating-coupled surface emitters
- Author(s): D.F. Welch ; R. Parke ; A. Hardy ; W. Streifer ; D.R. Scifres
- Source: Electronics Letters, Volume 25, Issue 13, p. 819 –820
- DOI: 10.1049/el:19890551
- Type: Article
- + Show details - Hide details
-
p.
819
–820
(2)
Surface-emitting lasers with second-order gratings for output coupling have been demonstrated to emit 2-8 W pulsed, with a differential efficiency of 20%. The radiation pattern resulting from the interference of two grating regions indicates coherent operation, and a single longitudinal mode output.
Role of velocity saturation in lifting pinchoff condition in long-channel MOSFET
- Author(s): V.K. Arora and M.B. Das
- Source: Electronics Letters, Volume 25, Issue 13, p. 820 –821
- DOI: 10.1049/el:19890552
- Type: Article
- + Show details - Hide details
-
p.
820
–821
(2)
The role of velocity saturation due to high–field mobility degradation in lifting the pinchoff condition in a longchannel MOSFET is described. The electric field on the drain end at the onset of current saturation is always extremely high leading to the velocity saturation of the carriers. This velocity saturation leads to the saturation value nsD =nsoV'g/2Vc = IDsat/qvth W on the drain end, in contrast with the well-known pinchoff behaviour, where the carrier density is shown to vanish at the saturation point. The carrier distribution, as well as the velocity distribution as a function of the channel distance along the length of the channel, is presented.
Improved dynamics and linewidth enhancement factor in strained-layer lasers
- Author(s): A. Ghiti ; E.P. O'Reilly ; A.R. Adams
- Source: Electronics Letters, Volume 25, Issue 13, p. 821 –823
- DOI: 10.1049/el:19890553
- Type: Article
- + Show details - Hide details
-
p.
821
–823
(3)
We show that a laser in which the active region consists of a strained-layer structure should have improved dynamics and noise characteristics. We find that the relaxation oscillation frequency is enhanced and the linewidth enhancement factor is reduced by strain.
Effects of deep-level states on current/voltage characteristics of heteroepitaxial GaAs
- Author(s): K. Das ; T.P. Humphreys ; N.R. Parikh ; J.B. Posthill
- Source: Electronics Letters, Volume 25, Issue 13, p. 823 –824
- DOI: 10.1049/el:19890554
- Type: Article
- + Show details - Hide details
-
p.
823
–824
(2)
The first results pertaining to current/voltage measurements of Au contacts fabricated on molecular beam epitaxial GaAs films grown on (1012) sapphire and silicon-on-sapphire (SOS) substrates are presented. A simple analysis of the corresponding l/V characteristics indicates that the dominant transport mechanism in these films is space-charge-limited current conduction in the presence of deep-level states. The nature of these deep-level states appears to be sensitive to the type of crystallographic defects present in the GaAs heteroepitaxial layers.
Enhanced time duration constraints in hidden Markov modelling for phoneme recognition
- Author(s): Y. Ariki and M.A. Jack
- Source: Electronics Letters, Volume 25, Issue 13, p. 824 –825
- DOI: 10.1049/el:19890555
- Type: Article
- + Show details - Hide details
-
p.
824
–825
(2)
The use of enhanced time duration constraints for subword (phoneme) recognition in continuous speech is reported. Here the time duration constraints are modelled by a Gaussian probability distribution in the conventional Baum-Welch learning algorithm and are statistically enhanced to obtain the most probable path in the Viterbi decoding process. Experimental results to validate this approach are included.
Modified Lu-Lee cryptosystems
- Author(s): Lin Xu-Duan and Cai Chang-Nian
- Source: Electronics Letters, Volume 25, Issue 13, page: 826 –826
- DOI: 10.1049/el:19890556
- Type: Article
- + Show details - Hide details
-
p.
826
(1)
Lu and Lee's cryptosystem has been proved to be insecure, and Adiga and Shankar's modified Lu-Lee system has been threatened by Kannan's algorithm. Here, we propose other modified Lu-Lee cryptosystems which use nonlinear encryption functions. The new systems seem to be secure.
Physical origin of negative differential resistance in SOI transistors
- Author(s): L.J. McDaid ; S. Hall ; P.H. Mellor ; W. Eccleston ; J.C. Alderman
- Source: Electronics Letters, Volume 25, Issue 13, p. 827 –828
- DOI: 10.1049/el:19890557
- Type: Article
- + Show details - Hide details
-
p.
827
–828
(2)
From a two-dimensional solution of Laplace's equation it is shown that a significant increase in temperature occurs in the channel of SOI transistors due to the relatively poor thermal conductivity of the buried insulator. Based on this simulation an equation is derived which predicts that at small channel lengths the pinchoft point is shifted, an effect which is consistent with experimental observations. In addition, the positive 'kink' is reduced with increasing gate voltage and this effect, together with the negative differential resistance, can be explained by a temperature increase in the channel.
100 GHz active electronic probe for on-wafer S-parameter measurements
- Author(s): R. Majidi-Ahy ; M. Shakouri ; D.M. Bloom
- Source: Electronics Letters, Volume 25, Issue 13, p. 828 –830
- DOI: 10.1049/el:19890558
- Type: Article
- + Show details - Hide details
-
p.
828
–830
(3)
We report the development of an active electronic probe for 100 GHz on-wafer S-parameter measurements. Integrated on the substrate of this wafer probe were a quintupler for 100 GHz stimulus signal generation, two directional couplers for incident and reflected signals sampling, and two newly developed harmonic mixers to down-convert these 100 GHz signals to 20 MHz. We have also demonstrated all-electronic on-wafer 75-100 GHz two-port S-parameter measurements using these probes.
Room-temperature operation of AlGaAs/GaAs resonant tunnelling structures grown by metalorganic vapour-phase epitaxy
- Author(s): R.D. Schnell ; H. Tews ; R. Neumann
- Source: Electronics Letters, Volume 25, Issue 13, p. 830 –831
- DOI: 10.1049/el:19890559
- Type: Article
- + Show details - Hide details
-
p.
830
–831
(2)
This letter reports improvements in resonant tunnelling through AlGaAs/GaAs double barrier quantum wells grown by metalorganic vapour-phase epitaxy. At room temperature peak-to-valley current ratios up to 2.4 and peak current densities of 1.9 × 104 A/cm2 are obtained.
1 Gbit/s, 32×32 high-speed space-division switching module for broadband ISDN using SST LSIs
- Author(s): N. Yamanaka ; S. Kikuchi ; Y. Yoshioka ; M. Suzuki
- Source: Electronics Letters, Volume 25, Issue 13, p. 831 –833
- DOI: 10.1049/el:19890560
- Type: Article
- + Show details - Hide details
-
p.
831
–833
(3)
A high-speed 32×32 space-division switching module for high-definition TV broadcasting and switching systems is described. It employs a newly developed Si-bipolar SST 8×8 switch LSI, high-speed peripheral ICs and a high-speed impedance-controlled board. The module is capable of a 10 Gbit/s signal speed using 1:1 and 1: n connections.
Behaviour of circuit-switched multistage networks in presence of memory hot spot
- Author(s): A. Pombortsis and C. Halatsis
- Source: Electronics Letters, Volume 25, Issue 13, p. 833 –834
- DOI: 10.1049/el:19890561
- Type: Article
- + Show details - Hide details
-
p.
833
–834
(2)
This letter addresses the important problem of evaluating the performance of tightly coupled multiprocessor systems under memory hot spot traffic by presenting an interference analysis of multistage interconnection networks (MINs) for such systems. It is shown that the tree saturation effect does not occur in nonblocking circuit-switched MINs.
Phase-noise-cancelling dual-frequency heterodyne optical fibre communication system
- Author(s): Y.H. Cheng and T. Okoshi
- Source: Electronics Letters, Volume 25, Issue 13, p. 835 –836
- DOI: 10.1049/el:19890562
- Type: Article
- + Show details - Hide details
-
p.
835
–836
(2)
An experimental 2OMbit/s PSK heterodyne system using a dual-frequency phase-noise-cancelling scheme has been constructed, and the bit error rate (BER) has been measured. The experimental result shows that the laser phase noise can be cancelled successfully.
More boundary conditions at double current sheet
- Author(s): J. van Bladel
- Source: Electronics Letters, Volume 25, Issue 13, p. 836 –837
- DOI: 10.1049/el:19890563
- Type: Article
- + Show details - Hide details
-
p.
836
–837
(2)
Boundary conditions across a double sheet of tangential currents are derived for En and Htang
Continuously tunable single-frequency laser diode utilising transverse tuning scheme
- Author(s): M.C. Amann ; S. Illek ; C. Schanen ; W. Thulke ; H. Lang
- Source: Electronics Letters, Volume 25, Issue 13, p. 837 –839
- DOI: 10.1049/el:19890564
- Type: Article
- + Show details - Hide details
-
p.
837
–839
(3)
A new wavelength-tunable single-frequency laser diode has been developed using a tunable twin-guide structure. The applied transverse tuning scheme provides a basically continuous tuning behaviour with only a single wavelength control current. The first 400μm-long, λ = 1.56μm devices are tunable over a range of 1.5 nm and show the expected continuous tuning behaviour.
Weighted overlap-add method for packet speech transmission
- Author(s): S.N. Koh and P. Sivaprakasapillai
- Source: Electronics Letters, Volume 25, Issue 13, p. 839 –840
- DOI: 10.1049/el:19890565
- Type: Article
- + Show details - Hide details
-
p.
839
–840
(2)
A novel system which employs the filter bank analysis and synthesis method for the packetisation of speech is proposed. Preliminary computer simulation studies of the system and informal subjective listening tests indicate that significant improvement in the perceptual quality of the recovered speech can be obtained, compared with the conventional technique of straight packetisation of PCM speech.
Second-order DFB lasers fabricated by deep UV contact lithography and GSMBE
- Author(s): E. Goarin ; D. Bonnevie ; M. Boulou
- Source: Electronics Letters, Volume 25, Issue 13, p. 840 –841
- DOI: 10.1049/el:19890566
- Type: Article
- + Show details - Hide details
-
p.
840
–841
(2)
DFB ridge waveguide lasers at 1.55μm with uniform second-order gratings defined by deep UV lithography have been realised for the first time. The lasers have been fabricated using gas source molecular beam epitaxial (GSMBE) hetero-structures grown in a two-step process. The characteristics of the DFB lasers (28 mA minimum threshold current, single-mode behaviour at output power in excess of 5 mW for more than 80% of the lasers and very low dispersion (±0.6nm) of the lasing wavelength) demonstrate that deep UV lithography can be successfully used for the fabrication of DFB lasers.
Double epitaxy improves single-photon avalanche diode performance
- Author(s): A. Lacaita ; M. Ghioni ; S. Cova
- Source: Electronics Letters, Volume 25, Issue 13, p. 841 –843
- DOI: 10.1049/el:19890567
- Type: Article
- + Show details - Hide details
-
p.
841
–843
(3)
A new single-photon avalanche diode (SPAD) with double-epitaxial silicon structure is presented. The device has a time response with short diffusion tail (270 ps time-constant), high resolution (45 ps FWHM, full-width at half maximum of the peak) and low noise, i. e. low dark-count rate.
Measurement of transmitted power in untapered multifibre unions: oscillatory spectral behaviour
- Author(s): P.R. Horche ; M.A. Muriel ; A.J. Martán-Pereda
- Source: Electronics Letters, Volume 25, Issue 13, p. 843 –844
- DOI: 10.1049/el:19890568
- Type: Article
- + Show details - Hide details
-
p.
843
–844
(2)
In the letter we show a new structure, the untapered multifibre union, with similar oscillation behaviour to that of tapered single-mode fibres. As a consequence conical regions are not relevant to the final results. This oscillatory behaviour opens the way to low-cost all-fibre devices such as optical filters.
Three-beam amplification in BSO crystals
- Author(s): D.C. Jones and L. Solymar
- Source: Electronics Letters, Volume 25, Issue 13, p. 844 –845
- DOI: 10.1049/el:19890569
- Type: Article
- + Show details - Hide details
-
p.
844
–845
(2)
It is shown that by applying the right detuning to two pump beams incident upon the BSO crystal from the same side, a third signal beam may be amplified. The maximum amplification was 12000 for a 1 cm-thick crystal which represents the highest value ever measured in BSO. It is further shown that the amplification strongly depends on the input power of the signal beam and full amplification is achieved for a beam ratio in excess of 107.
High-speed (ft = 78 GHz) AlInAs/GaInAs single heterojunction HBT
- Author(s): C.W. Farley ; M.F. Chang ; P.M. Asbeck ; N.H. Sheng ; R. Pierson ; G.J. Sullivan ; K.C. Wang ; R.B. Nubling
- Source: Electronics Letters, Volume 25, Issue 13, p. 846 –847
- DOI: 10.1049/el:19890570
- Type: Article
- + Show details - Hide details
-
p.
846
–847
(2)
High-performance AlInAs/GalnAs HBTs for low-power digital circuits have been demonstrated. Large-area devices exhibit high current gain (up to 600), observable down to low currents. Small-area devices display ft up to 78 GHz and fmax up to 45 GHz. Fitting S-parameter measurements to an equivalent circuit model shows that fmax is limited by a large RbCbc time constant in the base circuit. These transistors have been used to fabricate the first frequency divider demonstrated in this material system.
AlGaAs Schottky reflection modulator and detector for Gbit/s optical transmission systems
- Author(s): U. Prank ; W. Kowalsky ; T. Hackbarth ; K.J. Ebeling
- Source: Electronics Letters, Volume 25, Issue 13, p. 847 –849
- DOI: 10.1049/el:19890571
- Type: Article
- + Show details - Hide details
-
p.
847
–849
(3)
An electro-optic reflection modulator operated at incidence normal to the surface is presented attaining a switching contrast of 87:1 up to Gbit/s bit rates. The underlying mechanism is electroabsorption in the multilayered AlGaAs device. Operating the device for photodetection, we achieve a responsivity of about 1 A/W.
Mode field profile converting optical channel waveguide with tapered refractive index and cross-section
- Author(s): H. Yanagawa ; S. Nakamura ; K. Watanabe ; H. Miyazawa
- Source: Electronics Letters, Volume 25, Issue 13, p. 849 –850
- DOI: 10.1049/el:19890572
- Type: Article
- + Show details - Hide details
-
p.
849
–850
(2)
A mode field size converting optical channel waveguide with tapered refractive index and cross-sectional dimensions is proposed. The layer thicknesses and the core index of a silica waveguide were tapered along the waveguide by modulating the raw material gas flow in a flame hydrolysis deposition method. A channel width taper was also formed by photolithography.
Intermodulation and harmonic distortion in GaInAsP distributed feedback lasers
- Author(s): S.J. Wang and N.K. Dutta
- Source: Electronics Letters, Volume 25, Issue 13, p. 850 –852
- DOI: 10.1049/el:19890573
- Type: Article
- + Show details - Hide details
-
p.
850
–852
(3)
Measurements and calculations of intermodulation and harmonic distortion in 1.3μm high-speed distributed feedback lasers at multiGHz modulation frequencies are presented. The observed frequency and power dependence of the distortion levels are well explained by a perturbation analysis of the laser rate equations using parameters derived from the measured small-signal optical response of the laser.
Architecture design of optical customer premises network
- Author(s): H.J. Chao and L.S. Smoot
- Source: Electronics Letters, Volume 25, Issue 13, p. 852 –853
- DOI: 10.1049/el:19890574
- Type: Article
- + Show details - Hide details
-
p.
852
–853
(2)
A new optical customer premises network (CPN), which we call H-bus, has been designed to terminate future broadband ISDN signals and distribute the available bandwidth to terminal equipment connected to the CPN. The physical layer of the network makes use of the synchronous optical network (SONET) transmission format. The user information is carried using the asynchronous transfer mode (ATM) technique. The reliability of H-bus is improved through the use of a new optical component.
Novel transverse electro-optic waveguide phase modulator realised in titanium-diffused and proton-exchanged LiNbO3
- Author(s): S. McMeekin and R.M. de La Rue
- Source: Electronics Letters, Volume 25, Issue 13, p. 853 –855
- DOI: 10.1049/el:19890575
- Type: Article
- + Show details - Hide details
-
p.
853
–855
(3)
A new configuration for an electro-optic waveguide phase modulator, using electrodes transversely arranged on either side of a very thin substrate is described. The device has been tested with both titanium-indifTused and proton-exchanged waveguides in lithium niobate and used to estimate the electro-optic coefficients in the guides. Photorefractive effects have been observed in well-annealed single-mode protonexchanged waveguides at moderate power densities at λ = 0.6328 μm.
High-efficiency pulsed GaAs pin avalanche diodes for V-band oscillators
- Author(s): S. Huber ; M. Claassen ; H. Grothe
- Source: Electronics Letters, Volume 25, Issue 13, p. 855 –856
- DOI: 10.1049/el:19890576
- Type: Article
- + Show details - Hide details
-
p.
855
–856
(2)
GaAs pin avalanche diodes have been fabricated for millimetre-wave frequencies using molecular beam epitaxy. The highest obtained pulsed output power was 15 W with 8% efficiency at 50.1 GHz. The maximum observed efficiency was 11.1% at 57.4 GHz and 8.3 W output power.
CMOS quaternary latch
- Author(s): K.W. Current
- Source: Electronics Letters, Volume 25, Issue 13, p. 856 –858
- DOI: 10.1049/el:19890577
- Type: Article
- + Show details - Hide details
-
p.
856
–858
(3)
A new CMOS current-mode quaternary threshold logic latch circuit is presented. This circuit accepts and requantises quaternary logical currents during a SETUP clock mode and latches the input value during the HOLD clock mode. Using logical current increments of 10μA, the quaternary latch has been simulated to have a worst-case, three logic level transition, total SETUP and HOLD time of about 40 ns, and single level transition total SETUP and HOLD time of about 10 ns.
Effect of finite rectangular groundplane on near-in sidelobes of small linear slotted waveguide arrays
- Author(s): D.A. McNamara and L. Botha
- Source: Electronics Letters, Volume 25, Issue 13, p. 858 –860
- DOI: 10.1049/el:19890578
- Type: Article
- + Show details - Hide details
-
p.
858
–860
(3)
The effect of finite rectangular groundplane size on the sidelobes of linear slotted waveguide arrays is discussed.
Capacitive coupling of floating body well to sensitive nodes prevents high-resistance CMOS circuit from latching-up
- Author(s): M. Bafleur ; J. Buxo ; A. Elmoznine ; P. Rossel
- Source: Electronics Letters, Volume 25, Issue 13, p. 860 –861
- DOI: 10.1049/el:19890579
- Type: Article
- + Show details - Hide details
-
p.
860
–861
(2)
A new concept is derived whereby voltage transients occurring in the bulk substrate of a floating p− -well CMOS circuit can be conveniently decoupled near the sensitive n+/p− source-well parasitic junctions of n-channel transistors, thereby preventing latch-up occurrence. The ability of the well body to accommodate a nonequipotential situation is then taken advantage of to design a new and compact filter circuit that would certainly trigger latch-up if implemented on a grounded p−-well.
Abrupt high hole concentration profiles in GaAs by Zn+P dual implantation
- Author(s): A.C.T. Tang ; B.J. Sealy ; A. Rezazadeh
- Source: Electronics Letters, Volume 25, Issue 13, p. 861 –863
- DOI: 10.1049/el:19890580
- Type: Article
- + Show details - Hide details
-
p.
861
–863
(3)
In the letter we report that through the use of rapid thermal annealing (RTA) and the coimplantation of phosphorus an effective way of preventing the in-diffusion of zinc has been achieved. We have observed that the electrical activation characteristics of the Zn-implanted samples have been modified after the coimplantation of phosphorus. Furthermore, abrupt electrical profiles with hole concentrations of the order of 6×1019/cm3 have been achieved after annealing at 850°C for 30s.
Reduction of optical-feedback-induced frequency noise in pigtailed laser diodes
- Author(s): J.H. Midgley ; C.N. Pannell ; D.A. Jackson
- Source: Electronics Letters, Volume 25, Issue 13, p. 863 –864
- DOI: 10.1049/el:19890581
- Type: Article
- + Show details - Hide details
-
p.
863
–864
(2)
Two schemes for active cavity length control for close-coupled laser diode to butt-ended fibre are described and it is shown that at specific fibre-to-facet distances a significant reduction in feedback-induced laser frequency noise occurs.
Modelocking of AlGaAs laser diode by intracavity AlGaAs phase-modulator
- Author(s): J. BÖsl ; R. Bauer ; H. Rauch ; U. Penning ; G. Weimann ; W. Schlapp
- Source: Electronics Letters, Volume 25, Issue 13, p. 864 –866
- DOI: 10.1049/el:19890582
- Type: Article
- + Show details - Hide details
-
p.
864
–866
(3)
Active modelocking of an 830 nm AlGaAs laser diode by an intracavity AlGaAs phase-modulator is reported. The typical states of modelocking by pure phase-modulation, the even state, the odd state and double pulsing are demonstrated. The behaviour of a semiconductor laser in this experiment corresponds to that one known from the HeNe laser and Nd: YAG laser.
Digital model for switching transistors in series-gated ECL
- Author(s): C.S. Choy and C.Y. Ho
- Source: Electronics Letters, Volume 25, Issue 13, p. 866 –867
- DOI: 10.1049/el:19890583
- Type: Article
- + Show details - Hide details
-
p.
866
–867
(2)
A digital model is proposed that allows function verification and timing analysis of series-gated ECL to be performed on a logic simulator. Traditionally, an analogue simulator will be necessary because series-gated ECL circuits are constructed from transistors rather than primitive gates. The model is meant to replace each switching transistor in a series-gated ECL. A simulation time at least two magnitudes lower has been achieved.
Slow-wave microcoplanar variable phase shifter
- Author(s): A. Benghalia ; M. Ahmadpanah ; H. Baudrand
- Source: Electronics Letters, Volume 25, Issue 13, p. 867 –868
- DOI: 10.1049/el:19890584
- Type: Article
- + Show details - Hide details
-
p.
867
–868
(2)
The phase-shifting properties of a slow-wave microcoplanar structure are studied by means of a rigorous theoretical approach and the propagation losses are calculated. The Green function, which is used for the two-dimensional determination of the depletion layer profile, satisfies the real boundary conditions of the physical structure. The results obtained for the structure's electrical length are compared with the corresponding experimental data and a good agreement is obtained, in particular for zero-bias conditions.
Interference resonance of microstrip patch antenna fed with coaxial probe
- Author(s): J.P. Seaux ; A. Jecko ; A. Reineix
- Source: Electronics Letters, Volume 25, Issue 13, p. 868 –870
- DOI: 10.1049/el:19890585
- Type: Article
- + Show details - Hide details
-
p.
868
–870
(3)
This letter gives an interpretation of interference resonance in a microstrip patch antenna fed with coaxial probe and illuminated by electromagnetic pulses. An equivalent circuit is established over a wide frequency range. This circuit takes into account the interference resonance that we show in this study. Very good agreement is obtained between the analytical model, the numerical computation and the experimental measurements.
Full-wave analysis of microstrip leaky-wave antenna
- Author(s): M. Ghomi and H. Baudrand
- Source: Electronics Letters, Volume 25, Issue 13, p. 870 –871
- DOI: 10.1049/el:19890586
- Type: Article
- + Show details - Hide details
-
p.
870
–871
(2)
A full-wave analysis of a microstrip leaky-wave structure excited by the dominant LSM mode is presented. This approach is based on the waveguide model in which Galerkin's method is applied. Then, the far-field radiation can be computed from near fields using Fourier transforms.
W-band GaAs camel-cathode Gunn devices produced by MBE
- Author(s): R.B. Beall ; S.J. Battersby ; P.J. Grecian ; S. Jones ; G. Smith
- Source: Electronics Letters, Volume 25, Issue 13, p. 871 –873
- DOI: 10.1049/el:19890587
- Type: Article
- + Show details - Hide details
-
p.
871
–873
(3)
The DC and microwave performance of a novel secondharmonic W-band GaAs Gunn device incorporating a camel barrier are reported. Comparison with conventional Gunn devices shows significant improvement in power output and DC to RF conversion efficiency for the new structure. The frequency at which the maximum power is produced is lower for the camel cathode Gunn device, an observation attributed to a reduction in the length of the acceleration zone.
Translinear class AB current amplifier
- Author(s): C. Toumazou ; F.J. Lidgey ; M. Yang
- Source: Electronics Letters, Volume 25, Issue 13, p. 873 –874
- DOI: 10.1049/el:19890588
- Type: Article
- + Show details - Hide details
-
p.
873
–874
(2)
A new translinear class AB current amplifier is presented. Based on current-mode techniques, the circuit is readily configured into a high-performance voltage amplifier yielding wide gain-independent bandwidth and high slew rate, outperforming earlier designs.
Scheme for phase-locking a local oscillator in submillimetre-wave receiver
- Author(s): S. Padin
- Source: Electronics Letters, Volume 25, Issue 13, p. 874 –875
- DOI: 10.1049/el:19890589
- Type: Article
- + Show details - Hide details
-
p.
874
–875
(2)
A technique for phase-locking a low-power fundamental local oscillator in an SIS submillimetre-wave receiver is described. The arrangement uses the low-noise SIS mixer itself to downconvert the local oscillator signal from a Josephson junction or quantum well oscillator. A highfrequency phase-locked reference tone is required but for a typical SIS receiver the tone power is less than 10 nW. Even at terahertz frequencies this could easily be generated using a simple multiplier.
Practical gain of in-line semiconductor laser amplifiers
- Author(s): M. Sumida and M. Koga
- Source: Electronics Letters, Volume 25, Issue 13, p. 875 –877
- DOI: 10.1049/el:19890590
- Type: Article
- + Show details - Hide details
-
p.
875
–877
(3)
This letter proposes a novel coefficient called ‘practical gain’ which determines how much increase in transmission length a laser amplifier can provide. It confirms that a high-speed transmission system needs a laser amplifier with high saturation power.
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