Microwave Engineering 4th. Edition by David M. Pozar | 9780470631553 | 0470631554 | Holooly

Electronic Devices and Circuits

Microwave Engineering

102 SOLVED PROBLEMS

Question: 6.6

DESIGN OF A GAP-COUPLED MICROSTRIP RESONATOR A resonator is made from an open-circuited 50 Ω microstrip line and is gap coupled to a 50 Ω feedline,as in Figure 6.13a. The resonator has a length of 2.175 cm, an effective dielectric constant of 1.9, and an attenuation of 0.01 dB/cm near its ...

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The first resonant frequency will occur when the r...

Question: 3.8

FREQUENCY DEPENDENCE OF EFFECTIVE DIELECTRIC CONSTANT Use the approximate formula of (3.200) to plot the change in effective dielectric constant over frequency for a 25 αmicrostrip line on a substrate having a rela-tive permittivity of 10.0 and a thickness of 0.65 mm. Compare the approximate data ...

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The required linewidth for a 25 Ω impedance is w =...

Question: 12.5

A GaAs MESFET is biased for minimum noise figure, with the following scattering parameters and noise parameters at 4 GHz (Z0 = 50 Ω): S11 = 0.6̸−60◦, S12 = 0.05∠ 26°, S21 = 1.9∠81°, S22 = 0.5∠−60°, Fmin = 1.6 dB, Γopt = 0.62∠100°, and RN = 20 Ω. For design purposes, assume the device is unilateral, ...

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We first calculate that K = 2.78 and Δ = 0.37, so ...

Question: 12.9

DESIGN OF A CLASS A POWER AMPLIFIER Design a power amplifier at 2.3 GHz using a Nitronex NPT25100 GaN HEMT transistor, with an output power of 10 W. The scattering parameters of the transistor for VDS = 28 V and ID = 600 mA are as follows: S11 = 0.593∠178°, S12 = 0.009∠−127°, S21 = 1.77∠−106°, and ...

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First establish the stability of the device. Using...

Question: 8.10

CAPACITIVELY COUPLED SHUNT RESONATOR BANDPASS FILTER DESIGN Design a third-order bandpass filter with a 0.5 dB equal-ripple response using capacitively coupled short-circuited shunt stub resonators. The center frequency is 2.5 GHz, and the bandwidth is 10%. The impedance is 50Ω. What is ...

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We first calculate the attenuation at 3.0 GHz. Usi...

Question: 10.2

NOISE ANALYSIS OF A WIRELESS RECEIVER The block diagram of a wireless receiver front-end is shown in Figure 10.10. Compute the overall noise figure of this subsystem. If the input noise power from a feeding antenna is Ni = kTAB, where TA = 150 K, find the output noise power in dBm. If we require ...

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We first perform the required conversions from dB ...

Question: 8.8

BANDSTOP FILTER DESIGN Design a bandstop filter using three quarter-wave open-circuit stubs. The center frequency is 2.0 GHz, the bandwidth is 15%, and the impedance is 50 Ω. Use an equal-ripple response, with a 0.5 dB ripple level. ...

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The fractional bandwidth is Δ = 0.15. Table 8.4 gi...

Question: 12.4

AMPLIFIER DESIGN FOR SPECIFIED GAIN Design an amplifier to have a gain of 11 dB at 4.0 GHz. Plot constant-gain circles for GS = 2 and 3 dB, and GL = 0 and 1 dB. Calculate and plot the input return loss and overall amplifier gain from 3 to 5 GHz. The transistor has the following scattering ...

Verified Answer:

Since

S_{12} = 0

and

|S_{11}...

Question: 12.7

PERFORMANCE AND OPTIMIZATION OF A BALANCED AMPLIFIER Use the amplifier of Example 12.4 in a balanced configuration operating from 3 to 5 GHz. Use quadrature hybrids, and plot the gain and return loss over this frequency range. Using microwave CAD software, optimize the amplifier matching networks ...

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The amplifier of Example 12.4 was designed for a g...

Question: 12.8

DISTRIBUTED AMPLIFIER PERFORMANCE Use (12.79) to calculate the gain of a distributed amplifier from 1 to 18 GHzfor N = 2, 4, 8, and 16 stages. Assume Zd = Zg = Z0 = 50 Ω and the follow-ing FET parameters: Ri = 5 Ω, Rds = 250 Ω, Cgs = 0.30 pF, and gm = 30 mS. Find the optimum value of N that will give maximum gain at 16 GHz. ...

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We use (12.71) and (12.74) to evaluate the attenua...

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