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Online ISSN 1350-911X Print ISSN 0013-5194

Electronics Letters

Volume 28, Issue 1, 2 January 1992

Volumes & issues:

Volume 28, Issue 1

2 January 1992

Families of polyphase sequences with near-optimal two-valued autoand crosscorrelation functions
Algorithm for computing minimum product distance of TCM codes
All-optical clock recovery from 2.5 Gbit/s NRZ data using selfpulsating 1.58 μm laser diode
  • Author(s): P.E. Barnsley  and  J. Wickes
  • Source: Electronics Letters, Volume 28, Issue 1, p. 4 –6
  • DOI:  10.1049/el:19920003
  • Type: Article
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  • p. 4 –6 (3)
    For the first time, all-optical clock extraction from 2.5 Gbit/s NRZ data is demonstrated using a two contact InGaAsP semiconductor selfpulsating laser diode (SP-LD) for what the authors believe to be the first time. The saturable absorber region of the device was doped with Zn ions to reduce the carrier lifetime such that strong selfpulsations at frequencies up to 4GHz were obtained. Injection of a 10μW optical data singal at a wavelength ∼ 15 nm lower than the lasing wave-length was sufficient to synchronise the selfpulsations to the incoming NRZ data stream. Similar effects were seen for RZ foramted data. Such all-optical clock extraction tehcniques will find application in future multigigabit per second optical networks and for OEIC applications.
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Loss model for singlemode fibres
  • Author(s): M. Ohashi ; K. Sato ; Y. Katsuyama
  • Source: Electronics Letters, Volume 28, Issue 1, p. 6 –7
  • DOI:  10.1049/el:19920004
  • Type: Article
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  • p. 6 –7 (2)
    A modified Hanson model is proposed for the estimation of spectral loss. The approach to developing the model is based on multiple regression analysis. The model predicts spectral loss by using a vector containing the attenuation at three specified wavelengths of 1.31, 1.37, and 1.38 μm. The estimated errors between the measured and predicted losses are less than 0.02 dB/Km in the 1.23–1.60 μm wavelength region. This model will enable system designers to optimise systems with respect to the wavelength region without the need to use difficult procedures.
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Second substrate current peak and its relationship to gate-voltage dependent series resistance in submicrometre nMOS LDD
  • Author(s): E.A. Gutiérrez-D ; L Deferm ; G Declerck
  • Source: Electronics Letters, Volume 28, Issue 1, p. 7 –9
  • DOI:  10.1049/el:19920005
  • Type: Article
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  • p. 7 –9 (3)
    The occurrence of the second substrate current hump (SSCH) has been thoroughly investigated [1, 2, 3] and it is well known that the lateral electric field at the source sid4e (E5) is responsible for the appearance of the SSCH in sub-micrometre nMOS LDD transistors. However the fall off of the SSCH after reaching in maximum value. the so called second substrate current peak (SSCP), is not well understood and explained. In the Letter and improved model of the lateral electric field at the source side, which explains the SSCP in terms of the dependence of the source resistance Ris on the gate-source voltage, is introduced.
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New linewidth enhancement determination method in semiconductor lasers based on spectrum analysis above and below threshold
  • Author(s): Z. Toffano ; A. Destrez ; C. Birocheau ; L. Hassine
  • Source: Electronics Letters, Volume 28, Issue 1, p. 9 –11
  • DOI:  10.1049/el:19920006
  • Type: Article
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  • p. 9 –11 (3)
    Linewidth measurements of singlemode and multimode InGaAsP lasers were made above and below threshold with adapted interferometers. Linewidth against inverse power plots, Δv = f(1/P), show different Schawlow–Townes slopes above and below threshold. Differences have been observed depending on singlemode or multimode laser behaviour. In the singlemode case the linewidth enhancement factor has been determined (α = 2.6) by extrapolating and correlating results above and below threshold.
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Normalised frequency-domain adaptive filter based on optimum block algorithm
Uniform 8×8 array InGaAs/InP multiquantum well asymmetric Fabry–Perot modulators for flipchip solder bond hybrid optical interconnect
  • Author(s): A.J. Moseley ; M.Q. Kearley ; R.C. Morrie ; D.J. Robbins ; J. Thompson ; M.J. Goodwin
  • Source: Electronics Letters, Volume 28, Issue 1, p. 12 –14
  • DOI:  10.1049/el:19920008
  • Type: Article
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  • p. 12 –14 (3)
    The first 8×8 arrays of multiquantum well asymmetric Fabry–Perot modulators in the InGaAs/InP material system are reproted. These arrays have optical access through the substrate and are flipchip solder bond assembled for direct connection to silicon integrated circuits for optical interconnect applications. A high degree of uniformity of response is obtained across the array with a mean contrast ratio of 35 dB, with a standard deviation of 0.25 dB. Over a 4×4 mm2 chip the standard deviation of peak operating wavelength of the cavity resonance is 3.3 nm.
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Fully engineered coherent multichannel transmitters and receivers with low-cost potential
Form of field in small-offset longitudinal slot in broad wall of rectangular waveguide
X-band directive single microstrip patch antenna using dielectric parasite
  • Author(s): R. Afzalzadeh  and  R.N. Karekar
  • Source: Electronics Letters, Volume 28, Issue 1, p. 17 –19
  • DOI:  10.1049/el:19920011
  • Type: Article
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  • p. 17 –19 (3)
    A new method to enhance the gain of a single microstrip patch antenna using spaced superstates as a dielectric parasite is presented. The experimental results of radiation pattern using alumina parasites with different thicknesses and spacings are given. The minimum beamwidth obtainable with a single patch using present studies is only 18° with symmetric lobes in the H and E planes. This simple method can also be used to vary the beamwidth of the patch between 18 and 125° with proper choice of parasite parameters.
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Hot-carrier reliability in double-implanted lightly doped drain devices for advanced drams
  • Author(s): A. Ditali ; P. Fazan ; I. Khan
  • Source: Electronics Letters, Volume 28, Issue 1, p. 19 –21
  • DOI:  10.1049/el:19920012
  • Type: Article
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  • p. 19 –21 (3)
    Hot-electron degradation in short-channel (0.50 μm and 0.83 μm) double-implanted lightly doped drain (DI-LDD) devices was characterised using DC stress tests. Compared to lightly doped drain (LDD) devices of the same effective channel length Leff, the measurements indicate that channel hot-electron injection is more prevalent in devices with the p+-pocket implant due to a higher peak channel electric field. Degradation is more severe in both the drain current and transconductance. However, an improvement in shortchannel effects was seen in DI-LDD devices over LDD devices. For the same Leff, the punch-through voltage was higher and the subthreshold swing lower for the DI-LDD devices.
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Pulsed and CW high temperature operation of InGaAs/GaAs strained layer vertical cavity surface emitting lasers
  • Author(s): A. von Lehmen ; T. Banwell ; L. Carrion ; N. Stoffel ; L. Florez ; J. Harbison
  • Source: Electronics Letters, Volume 28, Issue 1, p. 21 –22
  • DOI:  10.1049/el:19920013
  • Type: Article
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  • p. 21 –22 (2)
    The performance of Strained layer InGaAs/GaAs vertical cavity surface emitting lasers defined by ion implantation over a ∼ 75°C temperature range is reported on. Maximum CW output levels for the temperature extremes of 10 and 86°C are 7.5mW and 200μW, respectively, for 20 × 20μm2 devices. The temperature dependence of the CW threshold current exhibits exponential behaviour to 80°C.
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Input and output queueing ATM switch architecture with spatial and temporal slot reservation control
New rate-1/3 trellis codes with 8-PSK signals for bandlimited AWGN channels
  • Author(s): L.H.C. Lee ; K.W.W. Leung ; Z.N. Lee ; M.L. Yau
  • Source: Electronics Letters, Volume 28, Issue 1, p. 24 –26
  • DOI:  10.1049/el:19920015
  • Type: Article
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  • p. 24 –26 (3)
    New rate-1/3; linear trellis (convolutional) codes with 8-PSK modulation for bandlimited additive white Gaussian noise channels are reported. The simulated bit error probability performance of the trellis-coded modulation schemes with unquantised Viterbi decoding shows useful coding gains over the uncoded coherent BPSK having the same bandwidth efficiency of 1 bit/s/Hz, and the schemes are suitable for use in many practical bandlimited channels.
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Programmable binary phase-only optical device based on ferroelectric liquid crystal SLM
Field programmable analogue array based on MOSFET transconductors
Ultrahigh-sensitivity low coherence otdr using Er1+-doped high-power superfluorescent fibre source
  • Author(s): K. Takada ; M. Shimizu ; M. Yamada ; M. Horiguchi ; A. Himeno ; K. Yukimatsu
  • Source: Electronics Letters, Volume 28, Issue 1, p. 29 –31
  • DOI:  10.1049/el:19920018
  • Type: Article
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  • p. 29 –31 (3)
    The first-known demonstration of an Er3+-doped superfluorescent fibre source coupled to a high-resolution OTDR based on low coherence interference (low coherence OTDR) is reported. Linearly-polarised light with 14 mW output from the source achieves a – 146dB minimum detectable reflectivity at 3 Hz bandwidth. The spatial resolution determined by spectral FWHM is 28 μm for silica-based waveguides.
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Novel RF oscillator using optical components
GaAs/AlGaAs delta-doped staircase avalanche photodiode with separated absorption layer
  • Author(s): M. Toivonen ; A. Salokatve ; M. Hovinen ; M. Pessa
  • Source: Electronics Letters, Volume 28, Issue 1, p. 32 –34
  • DOI:  10.1049/el:19920020
  • Type: Article
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  • p. 32 –34 (3)
    A GaAs/AIGaAs staircase SAM-APD containing a 10 stage undoped staircase multiplication region is demonstrated. Doping dipoles were inserted in GaAs/Al0.45Ga0.55As interfaces to increase the effective conduction band offset. Typical dark current at 0.9VB was 70pA. The maximum avalanche gain of 1500 was measured near the onset of breakdown. An effective ionisation rate ratio kaff = 0.2 was obtained from multiplication noise measurements.
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New tapered active fibres for very low noise amplifier applications
  • Author(s): A. Bjarklev ; O. Lumholt ; J.H. Povlsen ; T. Rasmussen ; K. Rottwitt ; S. Dahl-Petersen ; C.C. Larsen
  • Source: Electronics Letters, Volume 28, Issue 1, p. 34 –36
  • DOI:  10.1049/el:19920021
  • Type: Article
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  • p. 34 –36 (3)
    A new Er-doped fibre design for low noise amplifier applications is presented. The active fibre is continuously uptapered from the signal input end to the signal output end. Generated amplified spontaneous emission is thus reduced and high gain properties are preserved. Noise figure reductions of more than 0.5dB for copropagating pump and 2.0dB for counterpropagating pump are predicted.
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Dynamic latch for high speed GaAs domino circuits
  • Author(s): K.R. Nary  and  S.I. Long
  • Source: Electronics Letters, Volume 28, Issue 1, p. 36 –37
  • DOI:  10.1049/el:19920022
  • Type: Article
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  • p. 36 –37 (2)
    A latch for use with GaAs domino logic gates is presented. A hybrid of a GaAs domino logic gate and a two-phase dynamic FET logic gate, the latch stores data during the precharge phase of domino logic operation. It enables the use of domino logic in large scale systems without the need for interfacing with power consumptive static latches. It is implemented with depletion mode MESFETs and dissipates 0.8 mW.
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1.5<λ<1.7 μm strained multiquantum well InGaAs/InGaAsP diode lasers
Electron beam controlled latch operating under electron beam testing conditions
Analysis of radiative efficiency of long wavelength semiconductor lasers
Element dependency in dielectric tuning of frequency selective surfaces
Effects of chromatic dispersion, Kerr nonlinearity and amplifier noise in long PSK optical fibre systems
Metals semiconductor-metal photodector using Fe-implanted In0.53Ga0.47As
  • Author(s): M.V. Rao ; S.M. Gulwadi ; W.-P. Hong ; C. Caneau ; G.K. Chang ; N. Papanicolaou
  • Source: Electronics Letters, Volume 28, Issue 1, p. 46 –47
  • DOI:  10.1049/el:19920028
  • Type: Article
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  • p. 46 –47 (2)
    A two finger interdigitated metal-semiconductor-metal detector has been made using high-resistance Fe-implanted In0.53Ga0.47As material grown on InP:Fe. The fingers are 30μm long with 1μm width and 1.5μm separation. The breakdown voltage of the device is 5V. At 2V bias, the device has a dark current of 250 nA and a DC responsivity of 0.375 A/W at 13μm. The full width at half maximum of the response of the detector at 1.3μm is 260 ps.
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Genetic based training of two-layer, optoelectronic neural network
High-frequency operation of very low voltage, 1.55 μm single-mode optical waveguide modulator based on Wannier-Stark localisation
Pulses satisfying the Nyquist criterion
  • Author(s): J.O. Scanlan
  • Source: Electronics Letters, Volume 28, Issue 1, p. 50 –52
  • DOI:  10.1049/el:19920031
  • Type: Article
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  • p. 50 –52 (3)
    Pulses having zero intersymbol interference are necessary in data communications systems of various types. The requirement is that a bandlimited pulse p(t) is such that p(nT) = 0, n ≠ 0, and the well known cosine rolloff pulse is widely used in this context. The purpose of this Letter is to present a closed-form time-domain expression for generating all such pulses satisfying the Nyquist criterion, and to demonstrate that pulses exist which are superior to the cosine rolloff in terms of sensitivity to timing error.
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Monolithic integration of GaAs MSM photodetector and SiO2/Si3N4 dielectric optical waveguide
Fundamental phase noise limit in optical fibres due to temperature fluctuations
High linearity power operation of AlGaAs/GaAs HBT at 10 GHz
  • Author(s): N.L. Wang ; W.J. Ho ; J.A. Higgins
  • Source: Electronics Letters, Volume 28, Issue 1, p. 55 –56
  • DOI:  10.1049/el:19920034
  • Type: Article
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  • p. 55 –56 (2)
    Digital communication requires high linearity operation in both the receiver and the transmitter. AlGaAs/GaAs HBTs have achieved excellent saturated power operation throughout the microwave frequency range. The two-tone test of the HBT at 10 GHz was carried out on both CE and CB configurations. At −44 dBc IMD3, the CE HBT achieved 12 dB gain with a single carrier power density of 0.097 mW/μm2 and 5.8% collector efficiency. These results show that HBT linearity performance is as competitive as the MESFET in power transistor applications.
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Digital sampling process for audio class D, pulse width modulated, power amplifiers
  • Author(s): P.H. Mellor ; S.P. Leigh ; B.M.G. Cheetham
  • Source: Electronics Letters, Volume 28, Issue 1, p. 56 –58
  • DOI:  10.1049/el:19920035
  • Type: Article
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  • p. 56 –58 (3)
    Digital audio class D amplifiers require a digital process to convert the sampled audio signal into a pulse width modulated (PWM) signal. The present methods of generating PWM are either analogue (natural sampling) and are unsuitable for digital systems or use a digital process (uniform sampling) which introduces excessive distortion. An alternative sampling process is described which is suitable for digital implementation yet introduces the low levels of distortion usually associated with natural sampling.
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High efficiency, low threshold amplification and lasing at 0.8 μm in monomode Tm3+ -doped fluorozirconate fibre
Comment: State space models using simplified Routh approximation method
Lower bound of sample word length in bit/digit serial architectures
Microwave properties of free-standing dielectric films
  • Author(s): W.M. Robertson ; G. Arjavalingam ; G. Hougham ; G.V. Kopcsay ; D. Edelstein ; M.-H. Ree ; J.D. Chapple-Sokol
  • Source: Electronics Letters, Volume 28, Issue 1, p. 62 –63
  • DOI:  10.1049/el:19920039
  • Type: Article
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  • p. 62 –63 (2)
    Measurement of the broadband (15–150 GHz) microwave dielectric properties of free-standing films is demonstrated using the technique of coherent microwave transient spectroscopy. The accuracy of the method is verified by experiments on a fused silica sheet whose dielectric properties are well known. Results of measurements on (∼200μm thick) polymer films are presented.
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Zero-net-strain and conventionally strained InGaAsp/InP multiquantum well lasers
Coding to increase number of channels in QAM-SCM-IM/DD lightwave system
  • Author(s): J.H. Wu ; Y.-H. Lee ; J. Wu
  • Source: Electronics Letters, Volume 28, Issue 1, p. 65 –67
  • DOI:  10.1049/el:19920041
  • Type: Article
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  • p. 65 –67 (3)
    For a fibre-optic QAM-SCM-IM/DD system, clipping noise can severely limit the channel transport capability. A theoretical analysis of the QAM-SCM-IM/DD system employing BCH codes to increase the number of channels is presented. The relations among the system parameters such as received signal power, modulation index, and carrier-to-noise ratio are investigated. A general expression of the number of channels in terms of these parameters is also presented. The example shows that by using a (255, 239) BCH code, the number of channels can be increased up to fivefold, and the influence of clipping noise can also be greatly reduced.
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Energy quantisation in figure eight fibre laser
Enhancement of effective Schottky barrier height on n-type InP
  • Author(s): M.C. Ho ; Y. He ; T.P. Chin ; B.W. Liang ; C.W. Tu
  • Source: Electronics Letters, Volume 28, Issue 1, p. 68 –71
  • DOI:  10.1049/el:19920043
  • Type: Article
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  • p. 68 –71 (4)
    The effective Schottky barrier height on n-type InP is increased by a thin heavily-doped p-type surface layer grown by gas-source molecular beam epitaxy. The relationships between the barrier height increment and the doping level and thickness of the surface layer have been studied. The Schottky diodes fabricated by this method show reasonably low leakage current at high reverse bias and high reverse break-down voltage.
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Parallel acquisition of MR images using time multiplexed coils
Optimum multistage multirate switched capacitor architectures for highly selective interface filtering
  • Author(s): R.P. Martins  and  J.E. Franca
  • Source: Electronics Letters, Volume 28, Issue 1, p. 72 –75
  • DOI:  10.1049/el:19920045
  • Type: Article
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  • p. 72 –75 (4)
    Based on the cascade of switched capacitor decimating sections, with optimum implementation and operating with multiple clock rates, a new design methodology is proposed for implementing highly selective filtering functions for analogue-digital interface systems. When compared with more traditional designs, the proposed solution demonstrates remarkable savings both with respect to the capacitance spread and total capacitor area, and the speed at which the operational amplifiers have to operate. Both attributes are paramount for applications where chip size and power consumption are at premium.
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Coplanar waveguide aperture coupled patch antennas with ground plane/substrate of finite extent
  • Author(s): R.N. Simons  and  R.Q. Lee
  • Source: Electronics Letters, Volume 28, Issue 1, p. 75 –76
  • DOI:  10.1049/el:19920046
  • Type: Article
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  • p. 75 –76 (2)
    Coplanar waveguide (CPW)/aperture coupled microstrip patch antennas constructed with ground coplanar waveguide (GCPW), finite coplanar waveguide (FCPW) and channelised coplanar waveguide (CCPW) are demonstrated. The measured characteristics show that the CCPW/aperture coupled microstrip patch antenna has the largest bandwidth, whereas the GCPW/aperture coupled microstrip patch antenna has the best front-to-back ratio.
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Hysteresis effects in instantaneous frequency scaling of attenuation on 20 and 30 GHz satellite links
  • Author(s): D.G. Sweeney ; T. Pratt ; C.W. Bostian
  • Source: Electronics Letters, Volume 28, Issue 1, p. 76 –78
  • DOI:  10.1049/el:19920047
  • Type: Article
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  • p. 76 –78 (3)
    It has been observed with 20/30 GHz satellite beacon measurements that the ratio of 30 GHz to 20 GHz attenuation changes during some fade events. This ratio displays a hysteresis effect. This effect can be explained by a change in the drop size distribution (DSD) during the event. However it appears only above approximately 6–8 dB of attenuation at 20 GHz. Instantaneous frequency scaling of attenuation is being proposed as part of an algorithm for uplink power control (ULPC) and the dynamic range of such an algorithm must be appropriately limited to avoid the hysteresis.
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New broadband tunable monolithic microwave floating active inductor
Relative occurrence probabilities of minimum phase and nonminimum phase fades
  • Author(s): L. Martin  and  B. Giraud
  • Source: Electronics Letters, Volume 28, Issue 1, p. 81 –82
  • DOI:  10.1049/el:19920049
  • Type: Article
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  • p. 81 –82 (2)
    A semi-empirical method to compute the relative occurrence probabilities of minimum and nonminimum phase fades, occurring during selective fading, is presented. It is based on the assumption that the multipath fade depths at a single frequency are Rice distributed and that the total received power is constant. A Rice fade depth distribution can be parametrised with PR, the relative mean power of the received Rayleigh distributed vector. The relative occurrence probabilities of minimum and nonminimum phase fades, depending on PR, can then be computed for each radio path.
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Fast heterodyne optical phase-lock loop using double quantum well laser diodes
Thermo-optical modulation at 1.5μm in silicon etalon
InP/InGaAs double-heterojunction bipolar transistors with high speed, gain and current-driving capability
  • Author(s): M.L. Parrilla ; D.J. Newson ; J.A. Quayle ; M.D.A. MacBean ; D.J. Skellern
  • Source: Electronics Letters, Volume 28, Issue 1, p. 85 –86
  • DOI:  10.1049/el:19920052
  • Type: Article
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  • p. 85 –86 (2)
    InP/InGaAs double-heterojunction bipolar transistors (DHBTs) have been fabricated with an emitter area of 9 × 9 μm2 using a nonselfaligned process. Small-signal current gain in excess of 400 was obtained. Device measurements given an f1 = 39 GHz which, to the authors' knowledge, is the highest value reported for an InP/InGaAs DHBT. The value of f1 is in excess of 30GHz for a range of current densities from 8 to 100kA cm-2.
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Schottky-collector vertical PNM bipolar transistor
  • Author(s): S. Akbar ; S. Ratanaphanyarat ; J.B. Kuang ; S.F. Chu ; C.M. Hsieh
  • Source: Electronics Letters, Volume 28, Issue 1, p. 86 –87
  • DOI:  10.1049/el:19920053
  • Type: Article
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  • p. 86 –87 (2)
    A submicrometre inverted vertical PNM bipolar transistor with a platinum-silicide (PtSi) silicon Schottky collector-base diode and a p+n emitter-base diode is demonstrated. The transistor presents normal bipolar device characteristics with a DC current gain as high as 40. Faster switches can be made by using PNM transistors. They offer a desirable performance leverage when implemented in VLSI logic circuits.
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Swelling characteristics of proton-exchanged LiNbO3 waveguides
Series feedback integrated active microstrip antenna synthesis and characterisation
  • Author(s): V.F. Fusco
  • Source: Electronics Letters, Volume 28, Issue 1, p. 89 –91
  • DOI:  10.1049/el:19920055
  • Type: Article
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  • p. 89 –91 (3)
    A methodology for the optimal design of a FET based integrated active microstrip antennas is demonstrated; the electrical characteristics of the antenna are also discussed. The antenna consists of a rectangular microstrip patch peripherally loaded with a single GaAs MESFET. The microstrip patch acts as both the radiating element and the optimal FET drain load impedance required for oscillator synthesis. The active patch element operates as a series feedback oscillator and the microstrip patch is resonated in its fundamental mode. An NEC 71084 packaged FET is used as the active device in the patch element which itself is constructed on RT-Duroid 5880 material. The element has a free running frequency of 9.625 GHz (at 3 V) and exhibits excellent electrical characteristics. Experimental results are presented for the frequency pushing characteristics of the element which are nearly linear. The active element is capable of producing an output power level of 8mW with 10% efficiency at 2.3 V, and has an external Q factor of 32.
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Dynamic programming algorithm for linear prediction using thinned-lattice filter
  • Author(s): C.-F. Chan
  • Source: Electronics Letters, Volume 28, Issue 1, p. 91 –92
  • DOI:  10.1049/el:19920056
  • Type: Article
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  • p. 91 –92 (2)
    A new linear predictive modelling technique is introduced based on using a high-order lattice filter with only a few nonzero reflection coefficients. The objective of this modelling is to provide a better matching to the speech spectrum while keeping the number of bits for encoding the filter parameters low. An efficient algorithm based on dynamic programming techniques has been developed to find the nonzero coefficients and their corresponding delays for the thinned lattice filter.
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Dual-truncation ΔΣ digital-to-analogue convertors
Determination of line length using Hough transform
Matched filter for Gbit/s applications
30 Gbit/s multiplexer and demultiplexer ICs in silicon bipolar technology
  • Author(s): H.-M. Rein ; J. Hauenschild ; M. Möller ; W. McFarland ; D. Pettengill ; J. Doernberg
  • Source: Electronics Letters, Volume 28, Issue 1, p. 97 –99
  • DOI:  10.1049/el:19920060
  • Type: Article
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  • p. 97 –99 (3)
    A 2:1 multiplexer and a 1:2 demultiplexer IC fabricated in a 0.8 μm silicon bipolar technology were operated up to 30 Gbit/s. The increase in speed compared to former measurements is obtained by improving the mounting technique and the measuring setup and by increasing the clock voltage swing. This is the highest data rate reported for any monolithic integrated circuit in any semiconductor technology.
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Gain enhancement in Nd3+ doped ZBLAN fibre amplifier using mode coupling filter
Erratum: Signal linewidth broadening due to fibre nonlinearities in long-haul coherent optical fibre communication systems
Erratum: Novel amplifier gain insensitive switched capacitor integrator with same sample correction properties

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