Trigger 8E Description
Sequence: S05, ...
Trigger 8E ( Survey Mode, Nighttime/Periapsis )
This mode is designed to provide a survey mode, with fast temporal resolution and spectral resolution.
Both low-frequency and high-frequency WFR measurements are made, using "toggle" mode. Dust detection is included.
Langmuir Probe sweeps are performed every 640 seconds. A Sounder measurement is scheduled every 10 minutes.
MFDR measurements are made every 32 seconds, which provides MFR2 replacement data, while the LFR measurements
are also made every 32 seconds, providing the 25-Hz LFR data.
Beginning in S03, the HFR configuration was modified, in order to improve
the sensitivity for SEDs. The H2 integration period is increased to 40 ms,
the H1 integration period is increased to 40 ms, and the ABC integration
period is decreased to 500 ms.
| Receiver |
Frequency Range |
Sensors |
Time between Snapshots |
| LFR |
1 - 25 Hz |
EX, BX |
32 seconds |
| MFDR |
70 - 1700 Hz |
EX, BX |
32 seconds |
| MFR |
25 - 12 KHz |
EX, BZ |
32 seconds |
| WFR |
1 - 25 Hz |
EX,EW,BX,BY,BZ |
320 seconds |
| WFR |
.1 - 2.5 KHz |
EX,EW,BX,BY,BZ |
320 seconds |
| HFR |
3.6 KHz - 16 MHz |
EX, EW |
16 seconds |
| LP |
N/A |
Langmuir Probe |
640 seconds |
| Sounder |
3.6 - 115 KHz |
EX, EW |
600 seconds |
The HFR is in the newest version of "Nighttime Survey" mode, which now includes
both auto- and cross-correlations for H1, and modified integration constants for
all bands.
This mode is defined by:
Correlations Channels Integ. Size Frequency
Band Ant. Auto- Cross- per Band df Period Rep Steps kHz Start - Stop
---- ---- ----- ------ -------- -- ------ --- ----- ---- ------------
ABC 2E y y 16 n 500 1 3.6-319 kHz
H1 2E y y 2 n 40 1 60 25 325k-1.8MHz
H2 1E n n 1 n 40 1 72 200 1.8M-16MHz
Bands ABC require 1.58 sec to complete, H1 requires 2.85 sec, and H2 requires 2.53 sec
for a total of 6.97 sec per sweep. However, the time between analyses is set to 16
seconds to reduce the bit rate.
Every 600 seconds the HFR normal analyses are interrupted by a Sounder analysis.
Beginning in S05, the Sounder setup was modified. With the current configuration,
the Sounder operation has a duration of approximately 16 seconds.
This Sounder analysis is defined by:
sounder mode: EX AAA
1st sounder freq: 0
last sounder freq: 89
T1 delay: 5 msec
T2 delay: 5 msec
T3 delay: 15 msec
passive spectra: 2
active spectra: 2
# of cycles: 1
sounder output A: 3 autos
sounder output B: 3 AGCs