where ra, va are the unambiguous range and velocity, respectively, for wavelength
L and where c is the speed of light.Since the product
rava is a constant for a particular wavelength,
increasing either one (ra or va) necessarily
decreases the other. For L=10 cm (S-band) and a typical pulse repetition time (PRT)
of 1ms, ra=150km and va=25m/s. Weather phenomena routinely
exceed both of these limits. Phase coding of the transmit pulses for single
polarization radars has been shown to be an effective method for the separation of
range overlaid echoes thus extending ra without compromising va. NCAR has been funded
by the Radar Operations Center (ROC) of Norman, OK to investigate and implement
phase coding for real time operation on NCAR's S-Pol. The goal is to develop and
verify a phase coding
algorithm for the NWS (National Weather Service) WSR-88D radars. To date phase coding
statistical performance has only been shown for simulated Gaussian shaped weather
spectra. It is well know that weather spectra shapes can deviate significantly from
Gaussian. In this paper
examples of data quality improvement via SZ phase coding of
experimental S-band radar data are given. Statistical performance
plots are shown and compared to numerical simulations.
Installation of the new Sigmet RVP8 radar signal processor into S-Pol (due
to take place in May 2003) will make real time phase coding
for S-Pol possible. Results are given.
Installation of the new Sigmet RVP8 radar signal processor into S-Pol (due to take place in May 2003) will make real time phase coding for S-Pol possible. Results are given.