USER’S MANUAL__________________________________________________________________
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We would thus observe a velocity of (0.8 × V
u
) at 300 km, where V
u
is the
unambiguous Doppler velocity in meters/sec. Note that these phase
difference calculations have made no assumptions about the RVP900
processing mode, and thus are valid in all major modes (PPP, FFT, DPRT,
RPH), as well as in all Dual-PRF unfolding modes.
Interestingly, this simple FM signal generator will also produce valid
second trip velocities that can be seen during Random Phase processing.
This follows from the above analysis because we've never assumed that
τ
bin
was smaller than τ
s
, that is, it is fine for the range bin to be located in
any higher-order trip.
6.9.2 Verifying PHIDP and KDP
The PHIDP and KDP processing algorithms can be tested using CW signal
sources at IF. In the alternating-transmitter single-receiver case, a single
FM signal generator is modulated with an RVP900 polarization select line
so that slightly different frequencies are generated for the H and V pulses.
A maximum FM depth of several kilohertz is all that is required. In the
dual-receiver case, two (unmodulated) signal generators are used for each
of the H and V intermediate frequencies, and one or the other is detuned
slightly from its correct center frequency. In either case the frequency
difference that produces a KDP value of 1.0 degree/km will be:
6.9.3 Verifying RHOH, RHOV, and RHOHV
These three terms measure the normalized cross-channel covariance in a
polarization radar. They all are computed in essentially the same way
having the form:
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