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Figure 10.1: | Elements of a satellite communication network.
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Figure 10.2: | Orbits of geostationary satellites.
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Figure
10.3: |
Satellite of mass ms in orbit around Earth. For the
orbit to be geostationary, the distance R0 between the satellite and
Earth's center should be 42,164 km. At the equator, this corresponds
to an altitude of 35,786 km above Earth's surface.
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Figure
10.4: |
Elements of a 12-channel (transponder) communications
system.
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Figure 10.5: | Basic operation of a ferrite circular.
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Figure 10.6: | Polarization diversity is used to increase the number of
channels from 12 to 24.
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Figure 10.7: | Satellite transponder.
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Figure 10.8: | Spot and multi-beam satellite antenna systems for
coverage of defined areas on earth's surface.
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Figure 10.9: | Basic block diagram of a radar system.
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Figure
10.10: |
A pulse radar transmits a continuous train of RF pulses
at a repetition frequency fp.
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Figure
10.11: |
Radar beam viewing two targets at ranges R1 and R2.
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Figure
10.12: |
The azimuth resolution  x at a range R is equal to
 R.
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Figure 10.13: |
The output of a radar receiver as a function of time.
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Figure 10.14: |
Bistatic radar system viewing a target with radar cross
section (RCS)  t.
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Figure 10.15: |
A wave radiated from a point source when (a) stationary
and (b) moving. The wave is compressed in the direction of motion,
spread out in the opposite direction, and unaffected in the direction
normal to motion.
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Figure 10.16: | Transmitter with radial velocity ur approaching a
stationary receiver.
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Figure 10.17: |
The Doppler frequency shift is negative for a receding
target (0 <=  <= 90o), as in (a), and positive for an
approaching target (90o <= <= 180o), as in (b).
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Figure 10.18: |
Antenna feeding arrangement for an amplitude-comparison
monopulse radar: (a) feed horns and (b) connection to phasing network.
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Figure 10.19: |
A target observed by two overlapping beams of a
monopulse radar.
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Figure 10.20: |
Functionality of the phasing network in (a) the transmit
mode and (b) the receive mode for the elevation-difference channel.
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Figure 10.21: |
Monopulse antenna (a) sum pattern, (b)
elevation-difference pattern, and (c) angle error signal.
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