A microwave noise and gain parameter test set

Lane, Richard Q.

doi:10.1109/isscc.1978.1155852

Cited by 16 publications

(6 citation statements)

References 3 publications

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“…Ts -Td = 2GiGoT.Cos(8e + 6B -0) (5) where the correlated noise power referred to the input has been written T.exp(jO) = Tc.exp(j*c) + TdiS21 *S11 + TdoS22*S12 (6) In equation (5), 8-oi -to is the intrinsic phase difference between the arms, and OP = Pi -ao is the artificially introduced phase delay.…”

Section: The Interferometermentioning

confidence: 99%

“…In fact, the interferometer can be completely calibrated by measuring this single element. For example, when the DUT is replaced by a perfect series resistor R, having a uniform physical temperature Tp, equations (1), (5) and (6) show that the sum of the measured powers becomes Ps + Pd = kBi(Gi)2(Tai + 2r(l-r)Tp + Tdir2 + Tdo(i-r)2l…”

Section: Calibration and Measurementmentioning

confidence: 99%

“…Thirdly, the procedure is difficult to automate [4] unless varactor tuners [5] or long lengths of mismatched transmission line [6] are used. Fourthly, microwave transistors are unconditionally stable at low microwave frequencies, and it is difficult to guarantee stability when adjusting the noise source tuner.…”

Section: Introductionmentioning

confidence: 99%

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On the Feasibility of Measuring Transistor Noise Parameters with an Interferometer

Withington

1988

18th European Microwave Conference, 1988

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A new method is proposed for automatically measuring the noise parameters of microwave transistors. The basic apparatus is a heterodyne interferometer and this is used to measure the self and cross spectral powers associated with the noise waves which travel away from the input and output of the device under test (DUT).The interferometer can be fully calibrated by replacing the DUT with a mismatched shunt or series resistor.The technique is particularly suitable for characterising chip transistors, for measuring transistors at cryogenic temperatures, or indeed for any situation where the device is relatively inaccessible. INTRODUCT IONThe noise parameters of a microwave transistor are usually determined by measuring the effective input noise temperature as a function of the noise source reflection coefficient [1](2], and this requires a stub or dielectric tuner to be inserted between the noise diode and the device under test (DUT). There are a number of disadvantages with this approach.Firstly, the reflection coefficient and loss (3] of the tuner must be accurately known as a function of setting and frequency.Secondly, mechanical tuners are cumbersome and they can be unreliable. Thirdly, the procedure is difficult to automate [4] unless varactor tuners [5] or long lengths of mismatched transmission line [6] are used. Fourthly, microwave transistors are unconditionally stable at low microwave frequencies, and it is difficult to guarantee stability when adjusting the noise source tuner. A final criticism is that the technique cannot easily be extended to allow the noise parameters of multiport networks to be measured. It is proposed that all of these difficulties can be overcome by using an interferometer to measure the self and cross spectral powers associated with the noise waves which travel away from the various ports of the DUT. THE INTERFEROMETERThe block diagram of an interferometer which is suitable for measuring the noise parameters of microwave or millimetre-wave devices is shown in Figure 1. Circulators are inserted between the DUT and the first stages of low-noise amplification. This prevents the correlated noise power which originates in the interferometer from masking the correlated noise power which is generated by the DUT. The correlated system noise is eliminated because the noise waves which travel away form the inputs of the interferometer are absorbed by the noise diodes which are connected to the third ports of the circulators. Both of the circulators have noise diodes so that known amounts of noise power can be injected. A heterodyne system enables swept-frequency measurements to be made, however, in order to preserve the phase information in the required form, it is necessary to use image-reject sixers. Only a modest degree of image rejection is required and therefore wideband mixers can be constructed from quadrature hybrids. Once the travelling noise waves have been down converted to a conveniently

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Section: The Interferometermentioning

confidence: 99%

Section: Calibration and Measurementmentioning

confidence: 99%

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On the Feasibility of Measuring Transistor Noise Parameters with an Interferometer

Withington

1988

18th European Microwave Conference, 1988

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“…A traditional digital EIS is made by a set of switches combined with fi ed capacitors, which are placed periodically along a transmission line. The switches can be p-i-n diodes [2], [3], varactors [4], [5], [10], [11], monolithic microwave integrated circuits or transistors [12]- [17], and microelectromechanical systems (MEMS) switches [1], [6]- [8], [18]. The position of a capacitor can be varied virtually along the transmission line by choosing an appropriate switch.…”

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confidence: 99%

Nonuniformly Distributed Electronic Impedance Synthesizer

Zhao¹,

Hemour²,

Liu³

et al. 2018

IEEE Trans. Microwave Theory Techn.

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Benefiting from advantageous features of fast tuning, small size, and easy integration, the electronic impedance synthesizer (EIS) has been developed for on-wafer load-pull characterization systems, tunable matching networks, reconfigurable devices and systems, and so on. The previous designs of the EIS were mostly based on the empirical data instead of a closed-form design. Moreover, incomplete figures of merit (FOM) were chosen to optimize and evaluate the EIS. In this paper, we propose and present, first of all, a semiclosed-form design procedure for the distributed EIS. Then, a particle swarm optimization method is introduced to optimize the proposed nonuniformly distributed EIS, which comprises an adjusting circuit and a nonuniformly distributed circuit. Experimental results demonstrate that the proposed nonuniformly distributed structure can not only improve the Smith chart coverage but also reduce the size, compared to the uniform counterpart. The fabricated nonuniform EIS operating from 0.8 to 2.5 GHz, exhibits a good agreement between theory and measurement. Furthermore, the most comprehensive FOM are presented to evaluate the fabricated EIS.Index Terms-Electronic impedance synthesizer (EIS), electronic tuner, load-pull, nonlinear transmission line (NLTL), particle swarm optimization (PSO), reconfigurable device, tunable matching network (TMN).

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“…Thermal noise.Flicker NoiseFlicker noise is caused by traps associated with contamination and crystal defects in the emitter-base depletion layer. It is associated with a flow of direct current and displays a spectral density of the form[3]::--Kp[AF L1f 12 -f(19) where K F is a constant for a particular device, A F is a constant between 0.5 and 2, and ..df is the bandwidth in Hertz. This expression shows that the noise spectral density has a( 1 I f) frequency dependence, therefore, it is also called 1 I jnoise.…”

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confidence: 99%

Measurement Techniques for Noise Figure and Gain of Bipolar Transistors

Jung¹

2000

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First, the concepts of reflection coefficients, s-parameters, Smith chart, noise figure, and available power gain will be introduced. This lays out the foundation for the presentation of techniques on measuring noise figure and gain of high speed bipolar junction transistors. Noise sources in a bipolar junction transistor and an equivalent circuit including these noise sources will be presented. The process of determining the noise parameters of a transistor will also be discussed. A Pascal program and several TEKSPICE scripts are developed to calculate the stability, available power gain, and noise figure circles. Finally, these circles are plotted on a Smith chart to give a clear view of how a transistor will perform due to a change in source impedances.

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A microwave noise and gain parameter test set

Cited by 16 publications

References 3 publications

On the Feasibility of Measuring Transistor Noise Parameters with an Interferometer

On the Feasibility of Measuring Transistor Noise Parameters with an Interferometer

Nonuniformly Distributed Electronic Impedance Synthesizer

Measurement Techniques for Noise Figure and Gain of Bipolar Transistors

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