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Note: Many answers contain passages quoted in whole or in part from the text.
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quiz is based on the information presented in Monopulse Principles and Techniques, by Samuel M. Sherman
and David K. Barton.
1. What is another common term for monopulse?
b) Simultaneous lobe compression
Monopulse, also known as simultaneous lobe compression, is a method of determining the angular location of a
source of radiation or of a "target" that radiates part of the energy incident upon it. (see page xv)
2. What is the main unique feature of the monopulse technique?
d) A single
pulse provides information needed to obtain a pair of two-coordinate angle estimates
[Monopulse] was coined
because it clearly expressed the ability to collect from each pulse the information needed for a pair of
two-coordinate angle estimates, whereas the older angle-sensing techniques of sequential lobing required several
(at least four) pulses to form a pair of angle estimates. (see page 20)
What is the primary function of a Magic-T hybrid junction for radar purposes?
b) It provides high
isolation, sum and difference outputs from two independent inputs
...if inputs are applied simultaneously to
ports 1 (d in image) and 2 (b in image). their sum will appear at one of the outputs and their difference at the
other (a & c in image). (see page 58)
4. What are the two primary classes of
a) phase and amplitude comparison
Distinguishing between phase- and
amplitude-comparison monopulse (see page 93)
5. Which of these are methods
commonly used for beam steering?
d) All of the above
There are three principle methods of electronic
steering. (see page 127)
6. What is range rating?
a) Blocking received
signal from the receiver outside a specified time period
To enable the monopulse processor to reject extraneous
echoes and noise and to operate only on echoes received from the desired target, a range tracking loop keeps a
range gate (time gate) centered on the desired target. (see page 146)
7. What is
the main source of angular error in monopulse in low SNR conditions?
Noise is the dominant
source of angular error (or loss of track) under conditions of low signal-to-noise ratio, usually at long ranges.
(see page 226)
8. How does multipath affect monopulse performance?
Target resolution and tracking is degraded
Specular multipath causes erratic elevation tracking... Diffuse
multipath effects are somewhat noise-like and can be treated only statistically. (see page 271)
9. Which common ECM technique has little effect on monopulse?
a) Self-protection jammers
[Self-protection jammers] provide a strong, point-source signal that may actually improve monopulse tracking
accuracy. (see page 317)
10. What is squint angle?
c) Distance of a
focused beam from the primary antenna boresight
See Figure 1.4 (page 8)