CloudSat Over Wyoming Validation Experiment 27 Oct - 31 Dec 2006 Wyoming Cloud Radar Data Status Report Content: General Notes WCR configuration Radar Status/Problems Calibration Notes Data File Information Terminology and other notes ................................................................................ General Notes: * WCR raw data is archived and available on DVD disks. Quicklooks, dataquality, and calibration data is also recorded on these disks. Radar processed data files in NetCDF format are available usually within 2 months after the conclusion of the experiment (preliminary version may be available earlier). The NetCDF files are available via the Internet or on DVD disks. * Quick look images of co-pol reflectivity for all the flights are stored on the project WCR web site in their corresponding directories(mmmDD) as pdf files. ................................................................................ WCR configuration: WCR was installed on UWKA with four-antenna configuration: Antenna 1 2,3 and 4 and no polarization capability (for more see www-das.uwyo.edu/wcr); Antenna ports are: Ant1 (side/up) - H1, Ant2(near nadir) - V2, Ant3(side-forward) - V3, Ant4(down-forward) - H2; H/V stands for the receiver used (there are 2 receivers). Cross-channels (HXVX and VXHX channels) have no meaning for this configuration. Ant. 1 uses UWKA radar mirror wing to direct the radar beam side or up. The radar mirror events are recorded in the King Air data files. Mirror switching times are extracted in ascii files and placed under their corresponding flight day directories (file names: KAyyyymmdd.hhmmss_hhmmss.mirror) When the mirror file is not present a single positon (up or side) has been used during the flight. ................................................................................ Radar Status/Problems * V-ch drop happened in the flights from Oct26 to Dec05. Eventually the problem was traced down to a set of cables in the IF unit. They were replaced. * The scope is having some display/calibration/memory/measurement problems. Vp-p measurement on Ch2 does not work. * The VXI data system shows some problems, "ping" DSP fail status LED comes ON occasionally during initalization (once during operation) and a "panic" message for an "unrecoverable bus error exception" is displayed on the SPOS monitor. It appears that in addition to the DSP the VXI-PCI adaptor card also enters fail mode (fail status LED ON). Restart of the VXI and sometimes restart of the host computer as well fix the problem. ______ Oct 26 = V-ch dropped (as seen in the past 3 years); V-ch noise during the drop insreased and/or fluctuated by more than 10 dB ______ Nov 03 = V-ch dropped (this after the 2MHz filters for H- and V-ch were swapped) Larry Oolman reported that recycling DC power did not fix it, but changing from 500ns to 250 ns pulse fixed it. ______ Nov 12 = V-ch dropped (this after switching the the H- and V- ch. input filter switches). Jeff French reported that he first ran 500 ns pulse and after about 30-min V-ch dropped. He ran 250 ns pusles without problems. At the end of the flight he ran 500ns again for about 30 min without more V-ch drops. ______ Nov 14 = The 2nd pair of switches for the IF filter bank was swapped No V-ch drop occured during the flight. ______ Nov 28a = V-ch drop occured during the flight. ______ Nov 28b = V-ch drop occured at the end of the flight. ______ Dec 05 = VXI "ping" DSP card failed before take off. After cold restart it worked fine till the end of the mission. = V-ch dropped during the flight while running 500 ns. Switching to 250 ns recovered V-ch, then later running again 500ns worked fine for the rest of the flight. This event leads to exclusion of the cables used with the 2 Mz IF filter (which were swapped) as pssible explanation for the drop. ______ Jan 04 = Today flight was aborted after about an hour of flying due to a radar malfunction. Two problems were reported by Larry and Dave. The first one is the problem we have been experiencing lately with the "ping" DSP and interface cards. The second problem reported was a weak (severely attenuated) return from ground and clouds. The recorded data show that the power in the even profiles is severely attenuated while the received power in the odd profiles is fine. This is consistent with failing "ping" DSP but still running VXI data system ______ Jan 05 = Ground tests, no flight. = "PING" DSP card was replaced with the UMASS DSP card ______ Jan 31 = Jeff reported reduced received power in the first few minutes after running the radar on the ground outside the hangar. There is no information if the transmitter was the reason or the receiver (on the ground only up antenna is transmitting for testing and the scope was not working properly at the time) ______ Feb 08 = Larry reported frequent interruptions (loss) of H-ch when running 250 ns pulse (it was ok with 500 ns pulse). There is one occasion when V-ch dropped as well for about 10 sec (again 250 ns). ................................................................................ Calibration notes: **************************************************************************** Power Calibration: * Calibration constants for this experiment as of 17 Jan 2006 Calibration constants (250 ns pulse, 5 MHz IF filter, dynamic range > 70 dB; for 500 ns pulse subtract 3.5 dB): Ant. 1 (side/up), HHcal1 = 49.5 Ant. 2 (nadir), VVcal2 = 50.5 Ant. 3 (side-fore), VVcal3 = 57.0 Ant. 4 (down-fore), HHcal2 = 55.0 Calibration constant precision over the whole dynamic range (no less than 70 dB) is about +-1.0 dB for both receivers The absolute accuracy of the calibration constants for side/up and nadir antennas is estimated to be around +-2.5 dB (based on the overall variability of the calibration constants and the expected drift in the receivers and transmitted power). Transmitted power drift is estimated to be in the order of 1 dB for less than 2 hour flight and no more than 1.5 dB for longer flights. Receiver gain drift is estimated to be less than 1 dB. The accuracy of the calibration constants for slanted antennas (side-forward and down-forward) is not well established. Cloud data are used for relative calibration of these antennas w.r.t. side and nadir antennas. Slanted antennas are mostly intended for Doppler velocities. Cross-channel Isolation > 50 dB Antenna Coupling Separation: better than 50 dB; weak coupling between side and nadir antenna is possible for strong(close range) surface returns) * Calibration constants used for quick look images: Ant. 1 (side/up), calHH1 = 49.5 @ 250ns Ant. 2 (nadir), calVV2 = 50.5 @ 250ns Ant. 3 (side-fore), calVV3 = 57.0 @ 250ns Ant. 4 (down-fore), calHH2 = 55.0 @ 250ns **************************************************************************** Beam angles calibration: * Unit beam angles(in AC coordinates) for this experiment as of 18 Nov 2005 X(along AC) Y(right wing) Z(down) Ant. 1 (up): 0.052336, 0.000000, -0.9986295 Ant. 1 (side): -0.020885, 0.999784, -0.000000 Ant. 2 (nadir): -0.05512, 0.000235, 0.99848 Ant. 3 (side-fore): 0.5854, 0.8105, 0.02 Ant. 4 (down-fore): 0.4382, 0.004099, 0.89887 The accuracy of the beam angles for 'up' beam are not well known due to lack of calib data. For all other beams, an average bias between -0.5 and +0.5 m/s may be present in the Doppler velocities after removing the AC motion from the measured Doppler. **************************************************************************** ................................................................................ WCR Data File Information: ************************************************************************** oct26: (crew: Cooksey,Leon,Oolman,Wechsler) Test Flight Total data: 1.1 GB Alg/Pulse Antennas Notes 524M W2006-10-26-18-07-12 pp6/500 U,S,D V-ch drop,vnoise up >10dB 257M W2006-10-26-18-28-50 pp6/500 U,S,D V-ch drop,vnoise up >10dB 26M W2006-10-26-18-41-14 pp6/500 U,S,D V-ch drop,vnoise up >10dB 30M W2006-10-26-18-48-34 pp8/250 S,S,D,D 30M W2006-10-26-18-55-43 pp4/250 S,S beamcal 62M W2006-10-26-19-02-29 pp8/250 S,S,D,D beamcal 11M W2006-10-26-19-05-46 pp4/250 S,S beamcal 154M W2006-10-26-19-07-40 pp6/500 U,S,D ************************************************************************** nov03: (crew: Cooksey,Leon,Oolman,Wechsler) Total data: 1.5 GB Alg/Pulse Antennas Notes 101M W2006-11-03-19-36-15 pp6/500 U,S,D V-ch drop 19:38:25 734M W2006-11-03-19-41-28 pp6/250 U,S,D 624M W2006-11-03-20-10-34 pp6/250 U,S,D vnoise4-spike 49M W2006-11-03-20-43-03 pp8/250 S,S,D,D beamcal ************************************************************************** nov12: (crew: Cooksey,Leon,French,Kyoko Taniguchi) Total data: 3.0 GB Alg/Pulse Antennas Notes 544M W2006-11-12-08-14-49 pp8/500 U/S,S,D,D 510M W2006-11-12-08-31-08 pp8/250 U/S,S,D,D hnoise2,3;vnoise4-elev. V-ch dropped 8:44:50 733M W2006-11-12-08-47-48 pp8/250 U/S,S,D,D 808M W2006-11-12-09-09-43 pp8/250 U/S,S,D,D 115M W2006-11-12-09-33-53 pp8/250 U/S,S,D,D 524M W2006-11-12-09-38-07 pp8/500 U/S,S,D,D 421M W2006-11-12-09-53-48 pp8/500 U/S,S,D,D ************************************************************************** nov14: (crew: Cooksey,Leon,Oolman,Wechsler) Total data: 4.9 GB Alg/Pulse Antennas Notes 374M W2006-11-14-18-28-40 pp8/500 U/S,S,D,D vnoise4-elev. 944M W2006-11-14-18-40-06 pp8/500 U/S,S,D,D vnoise4-elev. 1.3G W2006-11-14-19-08-19 pp8/500 U/S,S,D,D hnoise-spike 929M W2006-11-14-19-45-16 pp8/500 U/S,S,D,D vnoise4-elev. 224M W2006-11-14-20-13-01 pp8/500 U/S,S,D,D hnoise2,3,4,vnoise4--elev. 132M W2006-11-14-20-19-47 pp8/500 U/S,S,D,D vnoise4-elev. 93M W2006-11-14-20-24-07 pp8/250 U/S,S,D,D hnoise2,vnoise4-spikes 989M W2006-11-14-20-29-47 pp8/250 U/S,S,D,D hnoise2-elev. KA data not available from 20:43:30-to end of file ************************************************************************** nov28a: (crew: Cooksey,Leon,French) Total data: 4.5 GB Alg/Pulse Antennas Notes 347M W2006-11-28-08-17-54 pp8/500 U/S,S,D,D V-ch drop(8:27:35-end) 2-sec time jump (~8:27) 146M W2006-11-28-08-33-12 pp8/500 U/S,S,D,D V-ch drop(8:36:04-end) hhnoise1-4 - comm. interf. 397M W2006-11-28-08-38-04 pp8/250 U/S,S,D,D 468M W2006-11-28-08-49-58 pp8/250 U/S,S,D,D 372M W2006-11-28-09-03-59 pp8/250 U/S,S,D,D 519M W2006-11-28-09-15-08 pp8/250 U/S,S,D,D vvnoise4-small elev. 597M W2006-11-28-09-30-39 pp8/250 U/S,S,D,D 411M W2006-11-28-09-48-32 pp8/250 U/S,S,D,D 422M W2006-11-28-10-00-50 pp8/250 U/S,S,D,D hhnoise,vvnoise-comm. interf. 114M W2006-11-28-10-13-38 pp8/250 U/S,S,D,D hhnoise2-elev. 413M W2006-11-28-10-17-08 pp8/250 U/S,S,D,D 353M W2006-11-28-10-32-18 pp8/250 U/S,S,D,D ************************************************************************** nov28b: (crew: Cooksey,Leon,French,Eidhammer) Total data: 3.4 GB Alg/Pulse Antennas Notes 621M W2006-11-28-19-30-23 pp8/500 U,S,D,D 543M W2006-11-28-19-48-56 pp8/500 U,S,D,D 526M W2006-11-28-20-05-11 pp8/500 U,S,D,D 461M W2006-11-28-20-20-54 pp8/500 U,S,D,D 496M W2006-11-28-20-34-42 pp8/500 U,S,D,D 621M W2006-11-28-20-49-31 pp8/500 U,S,D,D 180M W2006-11-28-21-08-05 pp8/500 U,S,D,D 24M W2006-11-28-21-15-08 pp8/500 U,S,D,D V-ch drop, RFh/v swap test ************************************************************************** dec05: (crew: Cooksey,Leon,French) Total data: 3.3 GB Alg/Pulse Antennas Notes 1.7M W2006-12-05-18-59-05 pp6/500 U,S,D V-ch drop 1.4M W2006-12-05-18-59-09 pp6/500 U,S,D V-ch drop 405M W2006-12-05-19-01-18 pp6/250 U,S,D 504M W2006-12-05-19-18-02 pp6/500 U,S,D 490M W2006-12-05-19-38-03 pp6/500 U,S,D 246M W2006-12-05-19-57-29 pp6/500 U,S,D vnoise4-elev. 690M W2006-12-05-20-07-50 pp8/500 U,S,D,D vnoise4-elev. 616M W2006-12-05-20-28-29 pp8/500 U,S,D,D vnoise4-elev. 374M W2006-12-05-20-47-01 pp8/500 U,S,D,D 36M W2006-12-05-21-36-08 pp4/250 S,S side beams cal., comm. interf. ************************************************************************** dec16: (crew: Cooksey,Leon,French) Total data: 3.2 GB Alg/Pulse Antennas Notes 480M W2006-12-16-18-34-57 pp6/500 U,S,D 493M W2006-12-16-18-54-01 pp6/500 U,S,D 464M W2006-12-16-19-13-35 pp6/500 U,S,D vnoise4-elev. 551M W2006-12-16-19-32-00 pp6/500 U,S,D vnoise4-elev. 581M W2006-12-16-19-53-53 pp6/500 U/S,S,D hnoise1-4:comm interf;vnoise-elev 131M W2006-12-16-20-16-57 pp6/500 U,S,D 33M W2006-12-16-20-25-08 pp6/250 S,D 250/500 calib 3.0M W2006-12-16-20-30-49 pp4/500 S,D 250/500 calib 8.8M W2006-12-16-20-32-35 pp4/250 S,D 250/500 calib 3.5M W2006-12-16-20-34-52 pp4/500 S,D 250/500 calib, hnoise3-elev. 440M W2006-12-16-20-39-05 pp6/500 U,S,D ************************************************************************** dec19: (crew: Cooksey,Leon,French,Wang) Total data: 5.9 GB Alg/Pulse Antennas Notes 498M W2006-12-19-18-57-18 pp8/500 U,S,D,D 507M W2006-12-19-19-12-12 pp8/500 U,S,D,D vnoise4-elev. 884M W2006-12-19-19-27-22 pp8/500 U,S,D,D vnoise4-elev. 487M W2006-12-19-19-53-53 pp8/500 U,S,D,D vnoise4-elev. 626M W2006-12-19-20-08-55 pp8/500 U,S,D,D vnoise4-elev. 510M W2006-12-19-20-27-39 pp8/500 U/S,S,D,D vnoise4-elev.,hnoise2,3,4-long spike 479M W2006-12-19-20-42-56 pp8/500 U,S,D,D vnoise4-elev. 498M W2006-12-19-20-57-16 pp8/500 U,S,D,D vnoise4-elev. 344M W2006-12-19-21-12-11 pp8/500 U,S,D,D vnoise4-elev. 7.7M W2006-12-19-21-24-13 pp6/250 S,D 250/500 20KHz calib,hnoise2-spike 3.3M W2006-12-19-21-26-29 pp4/500 S,D 250/500 20KHz calib 6.7M W2006-12-19-21-28-21 pp4/250 S,D 250/500 20KHz calib,hnoise2-spike 3.8M W2006-12-19-21-30-20 pp4/500 S,D 250/500 20KHz calib,hnoise2-spike 478M W2006-12-19-21-32-52 pp8/500 U,S,D,D vnoise4-elev. hnoise1-4:comm.interf 533M W2006-12-19-21-47-13 pp8/500 U,S,D,D ************************************************************************** jan04: (crew: Fagerstrom,Leon,Oolman) Total data: 74 MB Alg/Pulse Antennas Notes 44M W2007-01-04-18-49-20 pp8/500 U,S,D,D even profiles power missing 30M W2007-01-04-18-52-26 pp8/500 U,S,D,D even profiles power missing ************************************************************************** jan06: (crew: Cooksey,Leon,French) Total data: 2.1 GB Alg/Pulse Antennas Notes 467M W2007-01-06-19-36-32 pp8/500 U/S,S,D,D hnoise2,3,4;vnoise4-elev 466M W2007-01-06-19-51-46 pp8/500 U,S,D,D vnoise4-elev 472M W2007-01-06-20-06-49 pp8/500 U/S,S,D,D hnoise2,vnoise4-elev 576M W2007-01-06-20-22-04 pp8/500 U,S,D,D vnoise4-elev 168M W2007-01-06-20-40-42 pp8/500 U,S,D,D hnoise1-4-small interf. ************************************************************************** jan06: (crew: Cooksey,Z.Wang,French) Total data: 4.5 GB Alg/Pulse Antennas Notes 543M W2007-01-13-19-03-27 pp8/500 U,S,D,D vnoise4-elev 548M W2007-01-13-19-20-55 pp8/500 U,S,D,D 914M W2007-01-13-19-38-32 pp8/500 U,S,D,D vnoise4-spikes 497M W2007-01-13-20-08-01 pp8/500 U,S,D,D 698M W2007-01-13-20-24-01 pp8/500 U/S,S,D,D hnoise1,2,3,4-elev, interf.,vnoise4-spikes,elev 842M W2007-01-13-20-46-29 pp8/500 U,S,D,D vnoise4-elev 188M W2007-01-13-21-13-36 pp8/500 U,S,D,D 269M W2007-01-13-21-22-50 pp6/500 U,S,D 55M W2007-01-13-21-33-54 pp6/500 U,S,D ************************************************************************** jan31: (crew: Fagerstrom,Wang,French) - This is a dedicated WCL-WCR flight Total data: 2.1 GB Alg/Pulse Antennas Notes 454M W2007-01-31-17-49-23 pp6/250 U,S,D 473M W2007-01-31-18-08-06 pp6/250 U,S,D vnoise4-spikes 636M W2007-01-31-18-27-37 pp6/250 U,S,D h-ch drop from 5000 to 6000 prof around 18:30:30 486M W2007-01-31-18-53-48 pp6/250 U,S,D vnoise4-spikes 88M W2007-01-31-19-13-50 pp6/250 U,S,D ************************************************************************** feb08: (crew: Fagerstrom,Wang,Oolman) - This is a dedicated WCL-WCR flight Total data: 2.2 GB Alg/Pulse Antennas Notes 120M W2007-02-08-17-48-16 pp6/250 U,S,D h-ch drop after 17:49 69M W2007-02-08-17-56-36 pp6/250 U,S,D h-ch frequent drops, v-ch drop, 17:58:15-25 50M W2007-02-08-17-59-45 pp6/500 U,S,D 619M W2007-02-08-18-23-23 pp6/500 U,S,D vnoise4-elev. 946M W2007-02-08-18-48-53 pp6/500 U,S,D vnoise4-elev. 361M W2007-02-08-19-27-55 pp6/500 U,S,D hnoise- short radio inetrf ************************************************************************** ................................................................................ Terminology and other notes: Terminology used to acknowledge data quality for each data file reported under Data file indormation: 1) SPIKES are defined as short lasting (less than a few secs), large excursions in positive or negative direction (higher than 2-3 dB). 2) ELEVATED NOISE (including short spikes) is defined as occasional change in the mean noise that exceeds 2-3 dB and lasts from fraction of a second to more than a minute. It is usually associated with ground hits and/or multi-trip echoes. It is observed for side looking mode only. 3) NOISE JUMPS/SPIKES (up to 10-20 sec). Probably some sort of short interference not necessarily in both channels and in some cases associated with the mirror position change or A/C radio communications at freqs close to 120MHz 3) NOISE DRIFT is up to 2dB slow drift in the noise channel; likely due to drift in the receivers gain. Usually it does not exceed 0.5 dB. 4) BAD DATA refer to corrupted data or improbable data behavior. 5) DATA SHIFT means that all data channels are shifted one range gate to the right for one or both of the DSPs. 6) DATA GAPS: gaps between profiles exceeding several times the average time interval between profiles 7) TIME STAMP ERROR: known fixed shift in the time stamps. 8) TIME JUMPS: sync problem in the time which results in time stamps jumps including negative jumps 9) DATA DISCONTINUITY: unexpected jumps in reflectivity occurring thru all range gates from one profile to another. 10) V/H-MISSING or V/H severely attenuated reffer to unidentified problem causing severe attanuation or lack of signal from a target Other Notes: * WCR data acquisition system (DAQ) records time stamps from the vxi IRIG card which is slaved to the master KingAir data system IRIG card. The recorded time stamps are GPS time (currently 14 sec ahead of UTC). * The zero range gate, when at 75 m, is contaminated with the transmitter pulse leakage which appears at levels as high as -35 dBm@500ns (+15 dBZ). On the other hand very stong returns at 0 and 1st range gates are slightly undervalued (1 dB or less) due to receiver protection switches still residually closed. This range is in the antenna far field for the SideUp (12") antenna. Far fields for the 18" and 15" down antennas are 132 m and 91 m, respectively. Thus for the bigger antennas the first few range gates may have larger calibration errors. * When in side looking mode and maximum unambiguous range of 7.5 km, the data can be contaminated from second trip echoes, mostly from surface. Caution should be exercised when analyzing side looks. * Average DSP jumps (data jumps between two consecutive profiles due to data acquisition DSP) are mostly near zero for low power returns but frequently high power return (as indicated by the leak) exhibit jumps as high as 1-2 dB and thus averaging at least two profiles is recommended to reduce calibration errors. igh as 1-2 dB and thus averaging at least two profiles is recommended to reduce calibration errors.