Online ISSN
1350-911X
Print ISSN
0013-5194
Electronics Letters
Volume 12, Issue 15, 22 July 1976
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 12, Issue 15
22 July 1976
Solid-state microwave noise radar
- Author(s): J.R. Forrest and J.P. Meeson
- Source: Electronics Letters, Volume 12, Issue 15, p. 365 –366
- DOI: 10.1049/el:19760280
- Type: Article
- + Show details - Hide details
-
p.
365
–366
(2)
Microwave solid-state devices such as impatts can provide moderately high levels of noise power. A simple noise radar has been demonstrated using a cable delay line and correlator. Further experiments for greater range using variable s.a.w. delay lines and downconversion of the microwave signal are outlined.
Filtering secondary mirror for a dual-band Cassegrain reflector antenna
- Author(s): R.J. Langley and E.A. Parker
- Source: Electronics Letters, Volume 12, Issue 15, p. 366 –367
- DOI: 10.1049/el:19760281
- Type: Article
- + Show details - Hide details
-
p.
366
–367
(2)
A dual-frequency Cassegrain reflector antenna has been investigated in which the secondary mirror is constructed from a stack of waveguides. The secondary mirror behaves as a highpass filter, giving access to the prime-focus feed position at the higher-frequency band. The copolar and crosspolar radiation patterns are discussed.
Control of divergence in Kalman filters
- Author(s): F.M. Boland and H. Nicholson
- Source: Electronics Letters, Volume 12, Issue 15, p. 367 –369
- DOI: 10.1049/el:19760282
- Type: Article
- + Show details - Hide details
-
p.
367
–369
(3)
Techniques for control of divergence of the Kalman filter are considered. The application in practice of three decision-directed methods for divergence prevention is investigated. A critical study of the measures of filter quality and the control actions which these methods employ is presented and a new method is suggested for control of divergence in the standard filter.
Preparation of graded-index optical glass fibres in the alkali germanosilicate system
- Author(s): H.M.J.M. van Ass ; R.G. Gossink ; P.J.W. Severin
- Source: Electronics Letters, Volume 12, Issue 15, p. 369 –370
- DOI: 10.1049/el:19760283
- Type: Article
- + Show details - Hide details
-
p.
369
–370
(2)
Multicomponent glass fibres with a graded refractive index have been made in the alkali germanosilicate system using the double-crucible method. The index profile is based on Na+ ⇌ K+ ion exchange. Bulk-glass absorption losses of ≤10 dB/km at 752 nm have been measured. The present minimum level of fibre attenuation is 35 dB/km.
Integration of GaAs m.e.s.f.e.t.s and Gunn elements in a 4 bit-gate device
- Author(s): N. Hashizume and S. Kataoka
- Source: Electronics Letters, Volume 12, Issue 15, p. 370 –372
- DOI: 10.1049/el:19760284
- Type: Article
- + Show details - Hide details
-
p.
370
–372
(3)
A GaAs m.e.s.f.e.t. and a Schottky electrode-triggered Gunn element have been integrated into a single device which operated as a negative logic inhibitor. A monolithic device of four such inhibitors, connected in cascade, was operated in a stable manner, with a signal delay per gate as small as 40 ps.
New type of thermal-function i.c.: the 4-quadrant multiplier
- Author(s): V. Székely
- Source: Electronics Letters, Volume 12, Issue 15, p. 372 –373
- DOI: 10.1049/el:19760285
- Type: Article
- + Show details - Hide details
-
p.
372
–373
(2)
A new type of thermal-function i.c. is presented: the 4-quadrant multiplier. The design consists of three diffused resistance heaters and arrays of Si-Al contact sensors. The multiplier is quite linear and its frequency response is suitable for many applications. The structure is extremely simple and compatible with usual i.c. technology.
GaAs f.e.t. mixer operation with high intermediate frequencies
- Author(s): B. Loriou and J.C. Leost
- Source: Electronics Letters, Volume 12, Issue 15, p. 373 –375
- DOI: 10.1049/el:19760286
- Type: Article
- + Show details - Hide details
-
p.
373
–375
(3)
GaAs f.e.t. mixer operation is investigated at 6 GHz when the intermediate frequency is around 1 GHz. A 3 dB improvement in noise figure is measured, compared with 30 MHz i.f. operation. Other characteristics, such as conversion gain and dynamic range, are similar. Broadband operation is also investigated. With 0.5 μm gate device, on s.s.b. noise figure of 5.6 dB is achieved with a conversion gain of 10 dB.
High-speed transistor bistable circuits
- Author(s): E.V. Jones
- Source: Electronics Letters, Volume 12, Issue 15, p. 375 –376
- DOI: 10.1049/el:19760287
- Type: Article
- + Show details - Hide details
-
p.
375
–376
(2)
A bistable circuit is described which attempts to overcome some of the speed limitations of existing designs. Discrete-component realisations of the circuit have yielded toggle rates of up to 1.2 GHz.
Pitch synchronous differential predictive encoding system
- Author(s): C.S. Xydeas and R. Steele
- Source: Electronics Letters, Volume 12, Issue 15, p. 376 –378
- DOI: 10.1049/el:19760288
- Type: Article
- + Show details - Hide details
-
p.
376
–378
(3)
A pitch synchronous differential predictive encoding system (p.s.d.p.e.) is described, which reduces the dynamic range of voiced speech to a value similar to that of unvoiced speech. As a consequence, the signal encoded has a smaller dynamic range than the speech signal and results in an improvement in the signal/noise ratio for a given transmitted number of bits per sample. This improvement is approximately 8 dB compared with an a.d.p.c.m. codec, when the p.s.d.p.e. system uses an adaptive p.c.m. encoder and the transmission rate is 3 bit/sample.
Implementation of number-theoretic transforms
- Author(s): J.M. Pollard
- Source: Electronics Letters, Volume 12, Issue 15, p. 378 –379
- DOI: 10.1049/el:19760289
- Type: Article
- + Show details - Hide details
-
p.
378
–379
(2)
We propose various methods for the implementation of number-theoretic transforms to a prime or prime-power modulus. Such transforms may be performed in a processor or by special hardware. We also give, without proof, the condition for the existence of transforms in an arbitrary ring.
Improvements to delta-sigma modulators when used for p.c.m. encoding
- Author(s): J.D. Everard
- Source: Electronics Letters, Volume 12, Issue 15, p. 379 –380
- DOI: 10.1049/el:19760290
- Type: Article
- + Show details - Hide details
-
p.
379
–380
(2)
The letter describes some improvements to a delta-sigma modulator when it is used as part of a p.c.m. encoder for telephony applications. These improvements reduce the clock-rate requirements of the modulator, which would otherwise be excessive, and also minimise problems introduced by the use of low-precision components.
Computation of the gain-bandwidth performance of an X-band active reactance compensated IMPATT amplifier
- Author(s): C.S. Aitchison and A.S. Bains
- Source: Electronics Letters, Volume 12, Issue 15, p. 380 –382
- DOI: 10.1049/el:19760291
- Type: Article
- + Show details - Hide details
-
p.
380
–382
(3)
Results obtained from a computed gain–frequency response of an IMPATT amplifier, operating at 9.0 GHz with active reactance compensation, are reported. Measured values of the impedance of an impatt device, at an r.f. level of + 10 dBm and a direct current of 60 mA, are used. At 16 dB gain, the −1 dB bandwidth improves from 240 to 1450 MHz and from 110 to 560 MHz for the unencapsulated and encapsulated diode amplifiers, respectively.
Frequency synthesiser employing a bulk-acoustic-wave delay line
- Author(s): I. Browning and M.F. Lewis
- Source: Electronics Letters, Volume 12, Issue 15, p. 382 –383
- DOI: 10.1049/el:19760292
- Type: Article
- + Show details - Hide details
-
p.
382
–383
(2)
When a broadband s.a.w. delay line is used as the feedback element of an amplifier, one has an oscillator capable of operation at a comb of frequencies. This letter discusses some advantages of replacing the s.a.w. delay line by a conventional bulk-acoustic-wave delay line, and describes two techniques by which the frequency can be programmed reliably across the comb.
Design consideration for digital systems using multimode fibre with lossy cladding
- Author(s): R.J. Morgan
- Source: Electronics Letters, Volume 12, Issue 15, p. 383 –384
- DOI: 10.1049/el:19760293
- Type: Article
- + Show details - Hide details
-
p.
383
–384
(2)
Digital systems using multimode fibres with a step-index profile, a lossy cladding and a low-loss core are treated in the letter. The influence of fibre numerical aperture (n.a.) on repeater spacing is examined when the total core-cladding interface loss results from Fresnel reflection. It is shown, by way of example, that in this case there is no advantage in using low n.a. values, even at moderate modulation rates, owing to a diminishing receiver incident optical power with decreasing n.a.
Implementation of some ternary operators with c.m.o.s. integrated circuits
- Author(s): J.L. Huertas ; J.I. Acha ; J.M. Carmona
- Source: Electronics Letters, Volume 12, Issue 15, p. 385 –386
- DOI: 10.1049/el:19760294
- Type: Article
- + Show details - Hide details
-
p.
385
–386
(2)
A ternary gate which realises the basic operators of two different algebras is designed with c.m.o.s. integrated circuits. Both algebras have been selected because they are associated with powerful minimisation procedures. A delay time of 350 ns may be obtained.
Analogue f.d.m. telephony transmission in optical fibres: the limitations of intermodulation distortion
- Author(s): R. Horton
- Source: Electronics Letters, Volume 12, Issue 15, p. 386 –387
- DOI: 10.1049/el:19760295
- Type: Article
- + Show details - Hide details
-
p.
386
–387
(2)
The linearity of optical sources is a critical factor in analogue applications of optical fibres. The letter describes such considerations related to f.d.m. telephony, addressing both the l.e.d. and laser diode. From the information presented, conclusions are drawn on the viability of these applications.
Mechanical optical-fibre switch
- Author(s): P.G. Hale and R. Kompfner
- Source: Electronics Letters, Volume 12, Issue 15, page: 388 –388
- DOI: 10.1049/el:19760296
- Type: Article
- + Show details - Hide details
-
p.
388
(1)
An optical-fibre switch is described which depends on transverse mechanical motion of found fibres within a square-bore tube. The theoretical loss of the switch, when closed, can be as low as 0.05 dB and many tens of decibels when open.
D.C. matching errors in the Wilson current source
- Author(s): B.L. Hart and R.W.J. Barker
- Source: Electronics Letters, Volume 12, Issue 15, p. 389 –390
- DOI: 10.1049/el:19760297
- Type: Article
- + Show details - Hide details
-
p.
389
–390
(2)
A theoretical formula, accounting for parameter mismatch errors, and experimental measurements establish the necessity for using an additional transistor in the widely used Wilson current source if a direct-current transfer ratio centred on unity is to be achieved.
Double-error-correcting BCH codes for source encoding
- Author(s): J.P. Dion and S.G.S. Shiva
- Source: Electronics Letters, Volume 12, Issue 15, p. 390 –391
- DOI: 10.1049/el:19760298
- Type: Article
- + Show details - Hide details
-
p.
390
–391
(2)
It is known that error-correcting codes can be used to encode sources in the sense of data compression. We derive an expression for the average distortion per bit for double-error-correcting narrow-sense primitive BCH codes.
Erratum: Frequency response of a multiplexed charge-transfer delay line
- Author(s): S.C. Dutta Roy
- Source: Electronics Letters, Volume 12, Issue 15, page: 391 –391
- DOI: 10.1049/el:19760299
- Type: Article
- + Show details - Hide details
-
p.
391
(1)
Erratum: Performance of a 2-element adaptive array by a maximum-signal/noise-ratio algorithm
- Author(s): D.S. Hicks
- Source: Electronics Letters, Volume 12, Issue 15, page: 391 –391
- DOI: 10.1049/el:19760300
- Type: Article
- + Show details - Hide details
-
p.
391
(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
