Mars Express Bistatic Radar Experiment Operations Plan and Report 23 April 2006 Summary ======= DSN Antenna: 43 Pass: 1058 Orbit: 2930 Orbit Start Time: HGA Pointing: Inertial Specular Condition (ERT): 04:54 Target Latitude (deg N): -2.01 Longitude (deg E): -130.41 Rp (km): 3394.000 Incidence/Reflection Angle (deg): 38.74 Slant Range (km): 8672 Slew Angle (deg): 102.40 Doppler (carrier, fd; Hz): 13792 Doppler (echo, fr; Hz): -17583 Doppler Difference (fdd; Hz): 31375 Earth-Mars Distance (m): 2.765E+11 Experiment Set Up ================= This experiment was conducted using Canberra's DSS 43. Gene Goltz and Danny Kahan were in the Radio Science Support Area at JPL; Jesse Velasco was in the NOPE area, at least at the beginning. Dick Simpson was in occasional contact via phone from Donner Summit. The following report is based largely on notes provided by Goltz. Performance Problems and Notes ============================== There had been serious configuration problems during the BSR operation two days earlier (2006/111) at DSS 43. By day 113, these had been mostly resolved except that S-RCP and S-LCP had been swapped as inputs to the RSR's. It was not clear how this had happened; this had not been one of the issues on day 111. But it was deemed unimportant so far as performance of the system was concerned and the operation went forward without any attempt to fix it. Data Acquisition ================ RSRs were configured as in Table 1 (note that S-RCP and S-LCP are swapped compared with the usual assignments): Table 1 ---------------------------------------------------- RSR Channel Mode ATT FGAIN Operator dB ----- ------- ---- ---- ----- ---------------------- RSR1A S-RCP 1-W auto 60 Goltz RSR1B X-LCP 1-W auto 60 Goltz RSR2A S-LCP 1-W auto 60 Goltz RSR2B X-RCP 1-W auto 60 Goltz RSR subchannels (SCHAN) were defined as follows: Table 2 ---------------------------------------------------------------------- Subchannel Sample Rate Comments ---------- ----------- --------------------------------------------- 1 1 ksps backup (not recorded) 2 8 ksps backup (not recorded) 3 25 ksps Primary recording bandwidth 4 100 ksps Backup recording Table 3 lists ADC amplitude levels read from RSR displays during the experiment. Times are in UTC and should be considered approximate. "Steps" are as defined in the briefing message. RSR ATT settings are in units proportional to dB. Acronyms and abbreviations are explained after Table 3. Table 3 ----------------------------------------------------------------------------- Activity Time Step # S-RCP X-LCP S-LCP X-RCP Notes / Comments -------- ----- --------- ----- ----- ----- ----- ------------------------ Pre-Cal 1 01:54 att auto -10.0 -10.2 -10.0 -9.9 All to sky 01:46 2 -10.0 -0.3 -10.0 -0.0 X-Band to AMB 01:57 3 -10.0 -0.3 -0.5 -0.1 S-LCP to AMB 02:06 4 -0.3 -0.3 -0.5 -0.1 S-RCP to AMB AMB physical temps: S1=19.00, S2=17.44, X1=17.25 att auto 13.5 25.5 20.5 25.0 Reset ATT (prop to dB) -9.8 -10.0 -9.9 -9.8 Weather confitions: T=13C, H=43 percent sky=clear 02:10 rec 3 e Begin 25 kHz recording 02:10 5 -9.8 -10.0 -9.9 -9.8 Configure DTT's 02:15 6 -9.8 -10.0 -9.9 -9.0 XR ND ON 02:20 7 -9.7 -22.2 -9.9 -15.7 X-Band to sky 02:25 8 -9.7 -22.2 -10.0 -22.3 XR ND OFF 02:30 9 -9.8 -17.1 -9.9 -22.2 XL ND ON Confirmed 12.5K ND 02:35 10 -9.9 -9.4 -10.0 -9.8 X-Band to AMB AMB physical temps: S1=18.94, S2=17.88, X1=17.50 02:40 11 -9.8 -10.1 -9.9 -9.9 XL ND OFF 02:45 12 -9.8 -22.2 -9.8 -22.2 X-Band to sky 02:50 13 -9.6 -22.1 -10.0 -22.3 SR ND ON 02:55 14 -19.2 -22.0 -9.9 -22.3 SR to sky 03:00 15 -21.7 -22.2 -10.0 -22.2 SR ND OFF Confirmed 12.5K ND 03:05 16 -21.8 -22.0 -9.6 -22.1 SL ND ON 03:10 17 -21.7 -22.1 -18.6 -22.3 SL to sky 02:15 18 -21.7 -22.2 -21.3 -22.2 SL ND OFF AMB physical temps: S1=18.81, S2=18.56, X1=17.94 03:20 end Move antenna to point 03:26 BOT -20.2 -20.5 -19.8 -19.3 03:50 sfro 4/SX -5300 -19000 -5300 -19000 Rcvr offsets, SCHAN4(Hz) sfro 3/S -5300 0 -5300 0 Rcvr offsets, SCHAN3(Hz) 04:00 sfro 3/X 0 -34000 0 -34000 Rcvr offsets, SCHAn3(Hz) MiniCal1 04:05 1 -20.6 -21.2 -20.4 -15.0 XR ND ON 04:08 2 -19.9 -21.2 -20.3 -19.9 XR ND OFF, SR ND ON 04:11 3 -20.8 -17.0 -20.4 -20.0 SR ND OFF, XL ND ON 04:14 4 -20.2 -21.2 -18.0 -20.0 XL ND OFF, SL ND ON 04:17 5 -20.8 -21.2 -20.3 -20.1 SL ND OFF BSR 04:39 rec 4 e -21.0 -21.4 -20.4 -20.1 Start 100 kHz recording 04:54 Maximum echoes 05:09 rec 4 d -21.1 -21.6 -20.6 -20.2 Stop 100 kHz recording MiniCal2 05:25 1 -21.0 -21.6 -20.5 -15.2 XR ND ON 05:28 2 -19.1 -21.5 -20.7 -20.3 XR ND OFF, SR ND ON 05:31 3 -21.2 -17.1 -20.6 -20.3 SR ND OFF, XL ND ON 05:34 4 -21.2 -21.6 -18.3 -20.4 XL ND OFF, SL ND ON 05:37 5 -21.2 -21.5 -20.6 -20.3 SL ND OFF PostCal 06:05 EOT/stow -21.7 -22.3 -21.3 -22.4 06:10 1 -9.8 -10.1 -9.9 -9.9 All to AMB AMB phys temps: S1=20.52 S2=21.00 X1=18.31 06:15 2 -9.8 -10.2 -9.8 -9.0 XR ND ON 06:18 3 -9.5 -10.1 -9.8 -9.9 XR ND OFF, SR ND ON 06:21 4 -9.8 -9.4 -9.8 -9.9 SR ND OFF, XL ND ON 06:24 5 -9.7 -10.0 -9.4 -9.9 XL ND OFF, SL ND ON 06:27 6 -21.7 -22.1 -18.5 -22.2 All to sky 06:30 7 -21.7 -17.1 -21.2 -22.3 SL ND OFF, XL ND ON 06:33 8 -19.2 -22.1 -21.2 -22.2 XL ND OFF, SR ND ON 06:36 9 -21.7 -22.1 -21.2 -15.8 SR ND OFF, XR ND ON 06:39 10 -21.8 -22.1 -21.3 -22.2 XR ND OFF AMB physical temps: S1=20.75, S2=21.12, X1=18.69 Weather conditions: T=15C, H=38 percent sky=clear 06:45 rec 3 d Stop 25 kHz recording AMB = ambient load BOT = Beginning of Track CNR = Carrier to noise ratio CONSCAN = conical scan tracking CW = continuous wave (carrier only) EOT = End of Track FRO = frequency offset HGA = high-gain antenna LOS = loss of signal ND = noise diode No = noise power Pc = carrier power rcvr = receiver S1 = ambient load for S-RCP S2 = ambient load for S-LCP SL = S-LCP SNR = Signal to noise ratio SR = S-RCP TLM = telemetry X1 = Ambient load for both X-band channels XL = X-LCP XR = X-RCP Dick Simpson Original: 2006-05-02