Results 261 to 270 of about 669,562 (292)

Noise figure display with succeeding-stage noise compensation

Proceedings of the IEEE, 1971
Automatic display of noise figure by the usual method of noise reference modulation is limited to test objects with large power gain. It is shown that the noise contribution of succeeding stages is rendered ineffective when modulating the object under test.
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Figures of uncertainty for noise measurements

81st ARFTG Microwave Measurement Conference, 2013
In this paper we introduce two figures of uncertainty (FOU) for the assessment of noise figure measurements. These figures of uncertainty are readily determined if the scattering parameters of the device under test (DUT) are available. The two FOUs provide two types of information.
M. Seelmann-Eggebert, B. Baldischweiler, B. Aja, D. Bruch, H. Massler   +4 more
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A Theorem Concerning Noise Figures

IRE Transactions on Circuit Theory, 1956
A theorem is formulated and proved which determines the greatest lower bound of the single-frequency noise figure of a general system consisting of n amplifying devices and passive coupling elements. According to the theorem, this lower bound is equal to the noise figure of an optimum system using a selected one of these amplifying devices.
A. Bose, S. Pezaris
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The noise figure of junction transistors

Proceedings of the IEE - Part B: Electronic and Communication Engineering, 1959
An expression for the noise figure N of a junction transistor is derived from a noise equivalent circuit based on the theory of shot noise in p-n junctions, and on a transistor small-signal equivalent circuit. The thermal or Johnson noise generated in the a.c. extrinsic base resistance, rbb?, is included, while `excess?
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EDFA Noise Figure Standard

Optical Amplifiers and Their Applications, 1997
As Erbium Doped Fiber Amplifiers (EDFA) see increasing use in fiberoptic systems, there is a developing requirement to accurately compare and calibrate measurement systems used to characterize these ...
Roger L. Jungerman, James R. Stimple
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The noise figure of optical amplifiers

IEEE Photonics Technology Letters, 1998
The noise figure definition used for the characterization of optical amplifiers is critiqued. It is shown that it is inconsistent with the IEEE standard established for electronic amplifiers. A noise figure definition is proposed that is consistent with the IEEE standard and that is shown to be superior to the one currently in use.
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The noise figure of transistor converters

IRE Transactions on Broadcast and Television Receivers, 1961
The noise figure of a transistor converter may be expressed in terms of the usual transistor and circuit parameters (source resistance, base resistance, emitter-base diode impedance, current gain, cutoff frequency, and conversion conductance). Theoretical values are in good agreement with measured values.
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Some Notes on Noise Figures

Proceedings of the IRE, 1948
The subject matter of this paper first appeared in the form of laboratory reports. Outside interest in these reports prompted the preparation of the material for publication. Despite the attention given to noise and noise figures in the literature, the basic concepts are still little understood by the average engineer.
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Ultrasonic amplifier noise figure

Proceedings of the IEEE, 1968
Experimental ultrasonic noise figures of the CdS ultrasonic amplifier are presented along with values of drift potential at which noise saturation is observed to occur.
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The effect of feedback on noise figure

Proceedings of the IEEE, 1975
Exact formulas for the effect of series and Shunt feedback on noise figure are derived. The resulting noise figure is expressed by the feedback impedance, the two-port parameters, and the noise parameters of the device without feedback. The formulas are useful when considering the effect of biasing network and package elements on noise figure.
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