Trigger A8 Description
Sequence: C35
Trigger A8 ( RNGSAT, Rings & Satellite Regions )
This mode assumes a background survey mode, such as 8A or A0, is running,
and on top of that overlays fast WFR data acquisition. In order to do this,
the LFDR data acquisition is stopped (it can be synthesized on the ground,
using the fast WFR data.) A WFR snapshot, in its nominal 5-channel and
2048-sample mode, is acquired every 24 seconds. The WFR is run in toggle
mode, so these snapshots alternate between 25 Hz mode and 2.5 KHz mode.
In addition to stopping the LFDR data acquisition, the data compression
algorithm for the WFR is changed to "packed" mode, so that this faster
data rate can be accomplished. The target bit rate is 5800 bps. During
C35, in a short test, the measured bit rate was 5700 bps; this was using
trigger 8A as the background trigger.
| Receiver |
Frequency Range |
Sensors |
Time between Snapshots |
| MFR |
25 - 12 KHz |
EX, BZ |
32 seconds |
| WFR |
1 - 25 Hz |
EX,EW,BX,BY,BZ |
48 seconds |
| WFR |
.1 - 2.5 KHz |
EX,EW,BX,BY,BZ |
48 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 a modified "Composite Survey" mode, which now includes
both auto- and cross-correlations for H1.
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 1000 1 3.6-319 kHz
H1 2E y y 2 n 80 1 60 25 325k-1.8MHz
H2 1E n n 1 n 20 1 72 200 1.8M-16MHz
Bands ABC require 3.16 sec to complete, H1 requires 5.47 sec, and H2 requires 1.46 sec
for a total of 10.09 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.
The Sounder operation has a duration of approximately 40 seconds.
This Sounder analysis is defined by:
sounder mode: EZ AAA
1st sounder freq: 0
last sounder freq: 89
T1 delay: 10 msec
T2 delay: 25 msec
T3 delay: 25 msec
passive spectra: 2
active spectra: 2
# of cycles: 1
sounder output A: 3 autos
sounder output B: 3 AGCs