Mars Express Bistatic Radar Experiment Operations Plan and Report 18 July 2009 Summary ======= DSN Antenna: 14 Pass: 2240 Orbit: 7110 Orbit Start Time: 2009-07-18T10:28:53 HGA Pointing: Specular Start Center End -------- ---------- -------- Specular Condition (ERT): 12:56 13:30 14:03 Target Latitude (deg N): 46.37 53.19 16.31 Longitude (deg E): 48.98 75.57 119.58 Rp (km): 3394. 3394. 3394. Incidence/Reflection Angle (deg): 64.44 61.10 53.02 Slant Range (km): 7468. 4349. 797. Slew Angle (deg): 51.12 57.80 73.96 Doppler (carrier, fd; Hz): 30434. 39090. 19248. Doppler (echo, fr; Hz): 37635. 53679. 39203. Doppler Difference (fdd; Hz): -7201. -14589. -19954. Earth-Mars Distance (m): 2.728E+11 2.728E+11 2.728E+11 Experiment Set Up ================= This experiment was conducted using Goldstone's DSS 14. Danny Kahan and Gene Goltz were in the Radio Science Support Area (RSSA) at JPL. Dick Simpson was available by phone. Performance Problems and Notes ============================== Configuration of RSRs with respective feeds was different compared to the usual configuration (see Table 3); but all signals were available and recorded. Data Acquisition ================ RSRs were configured as in Table 1. Table 1 ---------------------------------------------------- RSR Channel Mode ATT FGAIN Operator dB ----- ------- ---- ---- ----- ---------------------- RSR2A S-LCP 1-W auto 60 UNK RSR3B X-LCP 1-W auto 60 UNK RSR3A S-RCP 1-W auto 60 UNK RSR2B X-RCP 1-W auto 60 UNK RSR subchannels (SCHAN) were defined as follows: Table 2 ---------------------------------------------------------------------- Subchannel Sample Rate Comments ---------- ----------- --------------------------------------------- 1 2 ksps Occultation bandwidth (not recorded for BSR) 2 8 ksps Occultation backup (not recorded for BSR) 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-LCP X-LCP S-RCP X-RCP Notes / Comments 2009/193 RSR2A RSR3B RSR3A RSR2B -------- ----- --------- ----- ----- ----- ----- ------------------------ fgain 09:36 60 60 60 60 GAIN = 60 dB Pre-Cal 10:14 1 -9.8 -9.5 -22.4 -10.0 ADC amplitude (dB) 10:17 att auto -9.8 -9.8 -10.1 -10.0 6.5 12.0 19.0 11.0 Attenuator settings (dB) 10:18 2 -9.7 -0.1 -10.1 -0.0 10:20 3 -2.8 -0.2 -10.1 -0.0 S-Band channels reversed 10:24 4 -2.8 -0.2 -0.6 -0.0 10:26 att auto -9.9 -9.8 -9.8 -10.1 Ambient load phys temps: S1=20.25 S2=25.25 X1=17.12 26.5 24.0 17.5 23.5 Attenuator settings (dB) Local weather: T=28.4C H=21.7 percent sky=clear 10:29 rec 3 e -10.0 -9.7 -9.9 -10.0 Begin 25 kHz recording 10:30 5 -10.0 -9.7 -9.9 -10.0 10:35 6 -10.0 -9.7 -9.9 -9.8 10:40 7 -10.0 -21.8 -9.1 -20.2 10:45 8 -9.7 -21.0 -9.9 -22.6 10:50 9 -9.9 -19.5 -9.9 -22.4 Confirm 12.5K ND 10:55 10 -9.8 -9.5 -9.9 -10.0 AMB load phys temps: S1=20.38 S2=24.94 X1=17.00 11:00 11 -9.9 -9.7 -10.0 -9.9 11:05 12 -9.8 -21.8 -10.0 -22.5 11:10 13 -9.8 -21.7 -9.7 -22.4 11:15 14 -9.9 -21.8 -19.3 -22.5 11:20 15 -9.9 -21.7 -20.8 -22.3 Confirm 12.5K ND 11:25 16 -9.6 -21.8 -20.8 -22.6 11:30 17 -15.9 -21.7 -20.8 -22.2 11:35 18 -16.6 -21.7 -20.9 -22.5 AMB load phys temps S1=20.50 S2=24.50 X1=16.69 11:40 end -16.1 -21.7 -20.9 -22.4 Stop 25 kHz recording BOT 12:05 -14.8 -21.2 -20.5 -20.4 X-band on 12:18 S-band on 12:33 rec 3 e Resume 25 kHz recording 12:35 -10.6 -21.4 -20.6 -20.6 Switch DSS 24 to Mars pointing predicts 12:40 sfro 3/SX +11K +10K +11K +10K MiniCal1 12:40 1 -11.5 -21.3 -20.7 -19.0 Confirm 12.5K ND 12:43 2 -12.0 -21.3 -19.1 -20.6 12:46 3 -10.8 -19.4 -20.7 -22.0 12:49 4 -12.1 -21.5 -20.8 -22.1 12:52 5 -13.9 -21.5 -20.7 -22.3 12:55 -12.2 -21.4 -20.8 -22.2 End MiniCal1 BSR 12:56 sfro 3 0 +1K 0 +1K Rcvr tuning offset (Hz) Begin 100 kHz recording -12.2 -21.4 -20.8 -22.2 13:16 sfro 3 +8K +8K Rcvr tuning offset (Hz) 13:38 sfro 3 +15K +15K Rcvr tuning offset (Hz) end BSR 14:03 sfro 3 +11K +10K +11K +10K Rcvr tuning offset (Hz) End 100 kHz recording MiniCal2 14:10 1 -12.7 -21.7 -20.8 -19.1 Confirm 12.5K ND 14:13 2 -15.2 -21.7 -19.2 =21.0 14:16 3 -12.2 -19.5 -20.8 -21.1 14:19 4 -13.3 -21.8 -20.9 -21.1 14:22 5 -11.3 -21.7 -20.9 -21.1 14:25 end -11.3 -21.7 -20.9 -21.1 sfro 3 0 0 0 0 Rcvr tuning offset (Hz) 14:30 -13.0 -21.7 -20.9 -21.1 Switch DSS 14 to S/C pointing predicts EOT 14:48 -10.0 -21.6 -20.9 -22.1 Move DSS 14 to stow PostCal 14:53 1 -9.9 -9.7 -9.9 -10.0 AMB load phys temps: S1=19.25 S2=23.94 X1=16.12 15:01 2 -9.8 -9.7 -9.8 -9.7 15:04 3 -9.8 -9.8 -9.6 -9.9 15:07 4 -9.8 -9.4 -9.8 -10.0 15:10 5 -9.6 -9.7 -9.8 -9.9 15:13 6 -13.5 -21.7 -20.9 -22.5 15:16 7 -14.4 -19.5 -20.8 -22.5 15:19 8 -13.3 -21.8 -19.2 -22.5 15:22 9 -16.0 -21.7 -20.8 -20.0 15:25 10 -15.1 -21.8 -20.9 -22.4 AMB load phys temps: S1=19.44 S2=23.94 X1=16.31 Local wseather: T=31.9C H=17.5 percent sky=clear EOA 15:29 end -12.7 -21.7 -21.0 -22.5 End 25 kHz recording AMB = ambient load BOT = Beginning of Track CNR = Carrier to noise ratio CONSCAN = conical scan tracking CW = continuous wave (carrier only) EOA = End of activity 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 Post Analysis Summary The table below summarizes the time division of X-Band data so as to capture the echo power as the signal drifted through the 25 kHz receiving passband. Spectra are 10-second averages (N=244). No carrier suppression was used. Interval Times Spectra Carrier Split Notes on Echo, FRO, etc. Bin Echo -------- ----------------- ------- ------- ----- ------------------------ A 12:56:00-13:16:00 001-120 337-332 001 Drifts slowly up AB 13:16:00-13:16:10 121 332 121 B 13:16:10-13:38:00 122-252 046 Drifts slowly up BC 13:38:00-13:38:10 253 046 253 C 13:38:10-13:54:00 254-348 Drifts slowly up D 13:54:00-14:03:00 349-402 Reverses, starts down Power estimate in spectrum 001 is incorrect because there is surface echo in The noise window before the FRO took effect. The table below summarizes the time division of S-Band data so as to capture the echo power as the signal drifted through the 25 kHz receiving passband. Spectra are 60-second averages (N=1464). No carrier suppression was used. Interval Times Spectra Carrier Split Notes on Echo, FRO, etc. Bin Echo -------- ----------------- ------- ------- ----- ------------------------ A 12:56:00-13:36:00 001-040 453 Drifts slowly up B 13:36:00-14:03:00 041-067 453 drifts up; turns around; Drifts down, broadens Dick Simpson Original: 2009-10-09 Updated geometry summary: 2009-11-02 Added Post Analysis Summary: 2009-11-05