Online ISSN
1350-911X
Print ISSN
0013-5194
Electronics Letters
Volume 8, Issue 20, 5 October 1972
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 8, Issue 20
5 October 1972
Apodised surface-wave transducers
- Author(s): W.H. Haydl
- Source: Electronics Letters, Volume 8, Issue 20, p. 493 –494
- DOI: 10.1049/el:19720357
- Type: Article
- + Show details - Hide details
-
p.
493
–494
(2)
A new method of fabricating surface-wave interdigital transducers is presented. The method allows a quick and simple variation of the apodisation, and many apodisation functions can be investigated on the same transducer. Results with a filter on yz lithium niobate are presented.
Calculation of characteristics of embedded coupled microstrip lines with finite thickness
- Author(s): S. Okugawa
- Source: Electronics Letters, Volume 8, Issue 20, p. 494 –495
- DOI: 10.1049/el:19720358
- Type: Article
- + Show details - Hide details
-
p.
494
–495
(2)
The letter gives a numerical method of determining characteristic impedances, propagation velocities and crosstalk parameters of coupled embedded (and unembedded or pure) microstrip lines from the relative permittivity of the substrate and geometrical data, such as the thickness of the strip conductor and that of the embedding layer. Some typical computed results are shown.
Logic array using charge-transfer devices
- Author(s): T.D. Mok and C.A.T. Salama
- Source: Electronics Letters, Volume 8, Issue 20, p. 495 –496
- DOI: 10.1049/el:19720359
- Type: Article
- + Show details - Hide details
-
p.
495
–496
(2)
A logic array that performs both AND and OR functions using charge-transfer devices is proposed. Potential barriers are used to control the directionality of charge transfer and perform the logic functions. The basic operation of the devices is described and illustrated using 2-phase charge-coupled devices.
New definition of multiple-root sensitivity
- Author(s): C.S. Phan and H.K. Kim
- Source: Electronics Letters, Volume 8, Issue 20, page: 497 –497
- DOI: 10.1049/el:19720360
- Type: Article
- + Show details - Hide details
-
p.
497
(1)
The sensitivity of a simple root of a polynominal is finite and well defined. For a multiple root, however, the existing definition becomes infinite, even when the root displacements remain finite. In this letter, a well behaved function is proposed to define a multiple-root sensitivity. It is also shown that the new definition, which degenerates to the conventional definition under a special condition, is a meaningful measure of actual root displacements.
Geometric criterion for the absence of limit cycles in nonlinear control systems
- Author(s): Jacob Rootenberg and Ralph Walk
- Source: Electronics Letters, Volume 8, Issue 20, p. 497 –499
- DOI: 10.1049/el:19720361
- Type: Article
- + Show details - Hide details
-
p.
497
–499
(3)
In most autonomous systems, the generation of periodic modes is considered to be an instability. Considering feedback systems composed of a time-invariant linear operator in cascade with an odd memoryless nonlinearity, a method is derived which provides a geometric interpretation of frequency regions in the Nyquist plane, over which simple oscillations cannot occur. This criterion answers a question of system behaviour when the Popov criterion is violated.
Improved microwave-transistor structure
- Author(s): J.A. Archer
- Source: Electronics Letters, Volume 8, Issue 20, p. 499 –500
- DOI: 10.1049/el:19720362
- Type: Article
- + Show details - Hide details
-
p.
499
–500
(2)
An improved microwave-transistor structure, in which the active and inactive base regions are formed by separate processes, is described. In this structure, a low base resistance is obtained by the use of a heavily doped inactive base region, which has a low sheet resistance and which also, by lateral diffusion, reduces the effective width of the emitter. At the same time, the active base region, formed by ion implantation, is separately optimised to improve the current-gain cutoff frequency. Transistors with the improved structure have noise factors of 2.3 dB at 4 GHz, compared with 3.6 dB for transistors with the same geometry but fabricated by the conventional double-diffusion process.
Effect of process variables on the microwave conductivity of thick-film conductors
- Author(s): J.R. Corkhill and E.R. O'Donnell
- Source: Electronics Letters, Volume 8, Issue 20, p. 500 –501
- DOI: 10.1049/el:19720363
- Type: Article
- + Show details - Hide details
-
p.
500
–501
(2)
This letter presents the preliminary results of an investigation into the effect of process variables on the microwave conductivity of thick-film conductors. The quality factor Q0 of 50 Ω closed resonators has been measured as a function of the firing temperature of the conductor and the mesh printing size. The results show that fine-mesh screens can be used without increasing the conductor losses, and that a high peak-firing temperature reduces the losses. The radio-frequency conductivity of the films as a fraction of bulk metal ranges from 0.45 at 1 GHz to 0.65 at 12 GHz.
Small-signal noise behaviour of companion p+-n-p+ and p+-n-v-p+ punchthrough microwave diodes
- Author(s): Gunnar Björkman and Craig P. Snapp
- Source: Electronics Letters, Volume 8, Issue 20, p. 501 –503
- DOI: 10.1049/el:19720364
- Type: Article
- + Show details - Hide details
-
p.
501
–503
(3)
The frequency and current dependence of the noise factor of tuned microwave amplifiers, utilising punchthrough injection transit-time diodes, has been determined. Noise factors as low as 10 and 11 dB were obtained from companion p+-n-p+ and p+-n-v-p+ structures, respectively, when tuned to frequencies in the vicinity of 7.5 GHz.
Computer-aided placement for high-density chip-interconnection systems
- Author(s): N.R. Crocker ; R.W. McGuffin ; R. Naylor
- Source: Electronics Letters, Volume 8, Issue 20, p. 503 –504
- DOI: 10.1049/el:19720365
- Type: Article
- + Show details - Hide details
-
p.
503
–504
(2)
A placement algorithm is presented for high-density chip-interconnection systems. The algorithm is novel in that the irregular nature of the pad positions and geometries of integrated-circuit chips are accommodated and used. The placement technique is based on the solution of a set of zeroth-order simultaneous equations, and is demonstrated by a simple example.
Comment on ‘Design of optimal-control systems with prescribed closed-loop poles’
- Author(s): B. Porter
- Source: Electronics Letters, Volume 8, Issue 20, p. 504 –505
- DOI: 10.1049/el:19720366
- Type: Article
- + Show details - Hide details
-
p.
504
–505
(2)
It is shown that certain results in inverse optimal-control theory can be used as the basis of a method for the design of optimal-control systems with prescribed dosed-loop poles which is much simpler and more direct than an iterative method recently proposed by Widodo.
Pole assignment in linear control systems
- Author(s): R.J. Widodo
- Source: Electronics Letters, Volume 8, Issue 20, p. 505 –506
- DOI: 10.1049/el:19720367
- Type: Article
- + Show details - Hide details
-
p.
505
–506
(2)
A design procedure is proposed to find the feedback vector, such that the closed-loop system achieves a set of prescribed poles. Based on normalised systems, the feedback vector can be directly expressed by the poles of the open- and closed-loop system.
First-order parameter sensitivities of nonlinear device models
- Author(s): P.F. Ridler
- Source: Electronics Letters, Volume 8, Issue 20, p. 506 –507
- DOI: 10.1049/el:19720368
- Type: Article
- + Show details - Hide details
-
p.
506
–507
(2)
This letter presents a method of obtaining the parameter sensitivities of device models for use in the determination of parameters by nonlinear optimisation. The method removes the necessity for any equation solutions, other than that required for the solution of the nonlinear circuit of the device itself.
Conductive contacting spheres on the centre of the broad wall of rectangular waveguides
- Author(s): P.I. Somlo and D.L. Hollway
- Source: Electronics Letters, Volume 8, Issue 20, p. 507 –508
- DOI: 10.1049/el:19720369
- Type: Article
- + Show details - Hide details
-
p.
507
–508
(2)
It has been found that metallic balls (held by external magnets) in rectangular waveguides produce a frequency-independent reflection, and an empirical formula is given for the magnitude of the reflection coefficient.
Simplified method for synthesis of distributed resistance networks
- Author(s): Cordell C. Hoffins
- Source: Electronics Letters, Volume 8, Issue 20, p. 508 –509
- DOI: 10.1049/el:19720370
- Type: Article
- + Show details - Hide details
-
p.
508
–509
(2)
A new distributed-resistance-network geometry is defined, which is suitable for the realisation of a wide variety of networks. An accurate, simplified synthesis procedure, based on a property of the linear fractional transformation and transmission-line concepts, is presented.
Amplitude dependence of frequency in oscillators
- Author(s): E. Vilar and P.A. Matthews
- Source: Electronics Letters, Volume 8, Issue 20, p. 509 –511
- DOI: 10.1049/el:19720371
- Type: Article
- + Show details - Hide details
-
p.
509
–511
(3)
The lower part of the f.m. spectrum in oscillators is discussed and experimental results at 36 GHz are compared with Edson's theory. The discrepancy found is explained by Blaquière's frequency-amplitude dependence, and the parameter involved in this dependence is evaluated by equating experimental and theoretical linewidths. The signal-power spectrum is also presented.
Novel method for numerical analysis of electron trajectories in electrostatic fields of implicit functional forms
- Author(s): Sadamu Kita ; Masahiro Hashimoto ; Kazuo Fujisawa
- Source: Electronics Letters, Volume 8, Issue 20, p. 511 –512
- DOI: 10.1049/el:19720372
- Type: Article
- + Show details - Hide details
-
p.
511
–512
(2)
A novel method for calculating 2-dimensional electron trajectories is given, which is useful for the case when the electric fields are expressed by implicit functional forms which are not suited to a conventional electron-trajectory analysis. This method is applied to parallel-plate and parallel-cylinder deflection systems.
Erratum: Active realisation of nth-order all-pass transfer functions
- Author(s): F. Anday
- Source: Electronics Letters, Volume 8, Issue 20, page: 512 –512
- DOI: 10.1049/el:19720373
- Type: Article
- + Show details - Hide details
-
p.
512
(1)
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
