AWR/XSACR/M1 - Low copol_correlation_coeff at Times

The VPT copol_correlation_coeff (RhoHv) is unusually low at times.  It only last the 
duration of the 15 minute scan normally and will be OK the next scan.  The cause of this is 
currently unknown and the data may actually be OK.  However, use with caution.

• Sky noise, copolar(sky_noise_copol)
• Mean doppler velocity(mean_doppler_velocity)
• Differential reflectivity(differential_reflectivity)
• Copolar correlation coefficient (also known as rhohv)(copol_correlation_coeff)
• Sky power, copolar(sky_power_copol)
• reflectivity(reflectivity)
• Differential propagation phase shift(differential_phase)
• Signal-to-noise-ratio(snr)
• Sky noise, cross-polarization(sky_noise_xpol)
• Sky power, cross-polar(sky_power_xpol)
• Doppler spectrum width (second moment of the doppler spectrum)(spectral_width)