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Note: Many answers contain passages quoted from the text.
Return to RF Cafe Quiz #50
quiz is based on the information presented in
Microstrip Lines and Slotlines, by Ramesh Garg, Inder Bahl, and Maurizio Bozzi.
House graciously provided this book.
Note: Some of these books are available as prizes in the monthly
RF Cafe Giveaway.
1. What is a principal requirement for a transmission structure to be
suitable as a circuit element in a microwave integrated circuit (MIC)?
d) It should be planar in configuration.
A planar configuration implies that the characteristics of the element can be determined by the dimensions in
a single plane.
(see page 1)
2. What are two consequences of the non-TEM
behavior of microstrip lines?
a) Dielectric constant and impedance are functions of frequency
Of these two, the variation of the effective dielectric constant is more significant.
(see page 21)
3. Which of the three drawings below represents the highest performance method
of transitioning from coaxial connector to microstrip?
(a) (b) (c)
c) Tapered transition
With the tapered transition, a 50 Ω impedance is maintained throughout
the transition rather than compensating for discontinuities.
(see page 30)
What is full-wave analysis?
b) Field analysis not invoking quasi-static approximations
Time-varying electric and magnetic fields must be considered when solving wave equations for microstrip (subject
to boundary conditions) since the system cannot be fully described in terms of static capacitances and inductances.
(see page 59)
5. What happens to the temperature of microstrip as the
c) Dielectric heating causes a temperature rise
type properties cause varying degrees (pun intended) of heating. Polystyrene, for instance, causes a lot of heating
compared to BeO.
(see Figure 2.13 on page 87)
6. What are examples
of discontinuities in microstrip?
d) All the above
Since discontinuities dimensions are usually
much smaller than the wavelength in microstrip, they may be modeled by lumped element equivalents.
7. Where does the wave propagate in a slotline?
In a slotline, the wave propagates along the slot with the major electric field component oriented
across the slot in the plane of metallization on the dielectric substrate.
(see page 239)
8. What is a Defected Ground Surface (DGS)?
c) An intentional deviation from
a continuous flat ground plane.
In DGS, the ground plane is intentionally modified to improve the frequency
response of the component.
(see page 305)
9. What is the distinguishing
feature of a coplanar waveguide?
b) All elements are collocated on the same surface of the substrate
The term "coplanar" is used for those transmission lines/waveguides where all the conductors reside in the same
plane; namely, on the top surface of the substrate.
(see page 347)
What is the name given to a configuration whereby two transmission lines are placed parallel to each other and in
a) Coupled line
In such a configuration there is continuous coupling between
the electromagnetic fields of the two lines.
(see page 433)
June 17, 2013