NSA/MPL/C1 - Detector Failure

Beginning 12/25, the signal return displayed serious aliasing, reflection, or ringing of 
the detector, with a highly repetitive pattern repeating six or more times within the 
lowest 15 km.  On 01/02, the detector became very difficult to put into any type of operating 
condition. When it did operate, the "aliased" signal pattern was still present.

The detector was replaced.

• Background signal standard deviation(background_signal_std)
• Laser Temperature(laser_temp)
• Laser output energy per pulse(energy_monitor)
• Attenuated backscatter(signal_return)
• Background Signal(background_signal)

NSA/MPL/C1 - Missing data

System was down for detector replacement.

• base time(base_time)
• time(time)
• Laser Temperature(laser_temp)
• effective range offset due to poor sync between laser firing and A/D trigger.(range_offset)
• lon(lon)
• Attenuated backscatter(signal_return)
• Dead time correction flag(dead_time_corrected)
• Array of heights for the range gates(height)
• range(range)
• lat(lat)
• Number of laser pulses summed during averaging interval(shots_per_avg)
• Telescope temperature(scope_temp)
• Polarization control voltage setting(polarization_control_voltage)
• Preliminary cloud base height(preliminary_cbh)
• Dummy altitude for Zeb(alt)
• Maximum altitude retrieved from multichannel scalar card.(max_altitude)
• Time offset of tweaks from base_time(time_offset)
• Background signal standard deviation(background_signal_std)
• Width of range-bins calculated from range_bin_time(range_bin_width)
• Number of bins stored in data block(num_bins)
• Detector Temperature(detector_temp)
• Repetition Rate, or Trigger Frequency of the laser(pulse_rep)
• Time in nanoseconds for each range bin of multichannel scalar card.(range_bin_time)
• Polarization control enabled flag(polarization_control)
• Distance from leading edge of first range bin to the center of each bin .(range_bins)
• Laser output energy per pulse(energy_monitor)
• Background Signal(background_signal)
• Number of detector channels(num_channels)

NSA/MPL/C1 - No cross polarized data

The cross polarizor was not functioning so there is no cross polarized data.  All data 
during the specified period is circularly polarized.

• Attenuated backscatter(signal_return)

NSA/MPL/C1 - Bad Cross-Polarized data

The polarizer box was not recycled when the system was rebooted; thus only circularly 
polarized light was being emitted.  Ignore all cross polarized data.

• Attenuated backscatter, cross-pol(signal_return_cross_pol)
• Background signal, cross-pol(background_signal_cross_pol)
• *(aqc_signal_return_cross_pol)
• Preliminary cloud base height above ground level, cross-pol(preliminary_cbh_cross_pol)
• Background signal standard deviation, cross-pol(background_signal_std_cross_pol)
• Polarization control voltage, cross-pol(polarization_control_voltage_cross_pol)

• Polarization control voltage setting(polarization_control_voltage)
• Attenuated backscatter(signal_return)

• Attenuated backscatter, cross-pol(signal_return_cross_pol)
• Polarization control voltage, cross-pol(polarization_control_voltage_cross_pol)
• *(aqc_signal_return_cross_pol)
• Background signal standard deviation, cross-pol(background_signal_std_cross_pol)
• Background signal, cross-pol(background_signal_cross_pol)
• Preliminary cloud base height above ground level, cross-pol(preliminary_cbh_cross_pol)

NSA/MPL/C1/C2 - No cross polarization data

Even though the polarization voltage was reported as switching between circular and cross 
polarization states, there was no cross polarization taking place because the 
polarization box had not been recycled following a system reboot.

You will not be able to create depolarization values.  However all other processes, such 
as cloud base determination should be ok.

• Attenuated backscatter, cross-pol(signal_return_cross_pol)
• Background signal, cross-pol(background_signal_cross_pol)
• *(aqc_signal_return_cross_pol)
• Preliminary cloud base height above ground level, cross-pol(preliminary_cbh_cross_pol)
• Background signal standard deviation, cross-pol(background_signal_std_cross_pol)
• Polarization control voltage, cross-pol(polarization_control_voltage_cross_pol)

• Polarization control voltage setting(polarization_control_voltage)
• Attenuated backscatter(signal_return)

• Attenuated backscatter, cross-pol(signal_return_cross_pol)
• Polarization control voltage, cross-pol(polarization_control_voltage_cross_pol)
• *(aqc_signal_return_cross_pol)
• Number of samples used for cross-pol averages(nsamples_cross_pol_average)
• Background signal standard deviation, cross-pol(background_signal_std_cross_pol)
• Background signal, cross-pol(background_signal_cross_pol)
• Preliminary cloud base height above ground level, cross-pol(preliminary_cbh_cross_pol)