Microwave Electronics 1st. Edition by Giovanni Ghione, Marco Pirola | 9781107170278 | 1107170273 | Holooly

Electronic Devices and Circuits

Microwave Electronics

61 SOLVED PROBLEMS

Question: 6.7

Discuss Fano’s limit to the input and output wideband matching of a transistor (FET or bipolar). ...

Verified Answer:

Consider the simplified equivalent circuit of a fi...

Question: 6.6

Show an example of a two-port having K > 1 but being potentially unstable. ...

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Consider a two-port with the scattering matrix: [l...

Question: 6.4

Consider, as in Example 6.3, a generator with internal resistance RG > 0 connected to a load RL. Investigate the behavior of the product |ΓG ΓL| (1) when RL assumes positive and negative values; (2) for different values of the normalization resistance R0. ...

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We have:

\left|\Gamma_G \Gamma_L\right|=\l...

Question: 6.3

A sinusoidal generator with open−circuit voltage EG = 1 V has internal resistance RG = 50 Ω. The generator is connected with a small−signal load RL = −25 Ω (provided, e.g., by a device with a local negative differential resistance). Analyze the power transfer within the circuit. ...

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The current flowing in the circuit (positive out o...

Question: 6.2

Show that the constant operational gain curves are circles in the ΓL plane, and find their center and radius. ...

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Reworking (6.22)

G_{ \text{op} }=\left|S_{...

Question: 6.1

Obtain (6.2) and (6.3). ...

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The maximum of

P_L

vs.

R_L[/...

Question: 9.1

Evaluate the scattering matrix of the directional bridge in Fig. 9.3 and show that the signal on the matched meter is proportional to the DUT reflectance. ...

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The scattering matrix of the bridge coupler can be...

Question: 8.8

Consider a class AB amplifier. Analyze the effect of power backoff due to the input power dependence of the circulation angle and derive the Pin − Pout relation. ...

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Suppose that the input bias of the class AB amplif...

Question: 8.7

A FET transcharacteristic can be approximated as a third−order polynomial as: iD (t) = a1 eG + a2 e²G + a3 e³G. Derive the corresponding descriptive function model around a carrier frequency f0 and show that the model correctly predicts the in−band third−order intermodulation products and also the ...

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Since the starting model is memoriless, the carrie...

Question: 8.6

A class A amplifier stage has a thermal resistance Rθ = 2 °C/mW. Taking into account that IDSS = 10 mA, VDS,br = 14 V and that the bias point is the optimum class A bias, estimate the temperature variation between two conditions: (a)zero input signal; (b)maximum input signal. Assume 20 dB ...

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The maximum class A power is:

P_{R F, M}=\...

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