A Dual Transmitter Hybrid Mode Polarization Radar operates in hybrid +-45 dual polarization mode. Orthomode feed of the radar antenna is rotated 45 degrees and one transmitter is used to feed the +45 channel and the other one to feed the -45 channel.
The two transmitters operate on different frequencies to enable separation of pulses on receive. The +-45 dual polarization data can be converted into H/V mode applying the rotation matrix:
(cos a sin a
-sin a cos a) ,where a is either +45 or -45
PHIdp information is not lost as would be the case if different frequencies were used in H and V channels. Instead, two separate sets of H/V polarization parameters will be obtained for +45 and -45 slant positions. These can be used to correct Zdr anomaly caused by nonzero canting angle as described in Bringi /Chandrasekar chapter 4.7.2. Due to different frequencies the anomaly is not completely eliminated but the result is better than without correction and an indicator is obtained for anomalous conditions.
As the Dual Transmitter Hybrid Mode Polarization Radar actually consists of two independent polarization radars the +45 and -45 channel pulses need not be transmitted simultaneously. Instead, two different constant pulse repetition times can be used. Difference of these pulse repetition times can be used to solve range/Doppler ambiguity while constant pulse repetition time of each channel will allow clutter removal with even sampling.
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