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Table 5 Example Tx/Rx Processing Algorithms
Algorithm Description
Phase Modulation Some radar processing algorithms rely on modulating the phase of the transmitter
from pulse-to-pulse.
This is traditionally done using an external IF phase modulator that is operated by
digital control lines. This requires additional hardware and cabling in the radar
cabinet, and the phase/amplitude characteristics may not be precise or repeatable.
RVP900 can perform precise phase modulation to any desired angle, without
requiring external phase shifting hardware.
Pulse Compression Placing radars in urban areas requires addressing strict regulations on transmit
emissions.
Because the peak transmit power is often limited in these areas, the weather radar
must illuminate its targets using longer pulses at lower power. However, a simple long
pulse lacks the ability (bandwidth) to discern targets in range.
The solution is to increase the Tx bandwidth by modulating the overall pulse envelope
to restore a reasonable range resolution. The fidelity of the RVP900 waveform can
accomplish this without introducing the spurious modulation components that often
occur when using external phase modulation hardware.
Frequency Agility RVP900 frequency agility makes this as simple as changing the center frequency of
the synthesized IF waveform. Many Range/Doppler unfolding algorithms become
possible when multiple transmit frequencies can coexist.
Frequency agility can also be combined with pulse compression to remedy the blind
spot, at close ranges, while the long pulse is being transmitted.
COHO synthesis RVP900 output waveform can be programmed to be a simple CW sine wave. It can
be synthesized at any desired frequency and amplitude, and its phase is locked to the
other system clocks.
This is an easy way to get a dedicated oscillator at a random frequency in the IF band.
RVP900 User Guide M211322EN-J
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