Trigger BC Description
Sequence: C38, C39, ...
Trigger BC ( HRSKR 182 kbps Hirate Mode )
This mode is designed to provide a hirate mode for analyzing fine structure of SKR,
while also providing a low temporal resolution spectrum at the nominal frequency resolution.
This is accomplished by running the WBR in the "down-convert" mode, using the 25-KHz
wide signal provided by the HFR, which is simultaneously running in millisecond at
the frequency provided to the WBR. This mode of operation is paused every 64 seconds
for 8 seconds, in order to perform a normal analysis sweep, nominally in SEDDF mode.
At this time, the LFDR/MFDR is also sampled. These provide the low temporal resolution spectrum.
At each 64-second interval the millisecond mode frequency is toggled between each of two
selections: 225 kHz and 325 kHz. These frequencies could be tweaked with additional commands.
WFR data acquisition and Dust detection are not done. Langmuir Probe sweeps are performed
every 640 seconds. The Sounder is disabled in this trigger.
It is assumed that prior to this trigger, either trigger A0 (SEDDF) or trigger
8E (Night-Time Survey) was in effect.
| Receiver |
Frequency Range |
Sensors |
Cycle Time |
Snapshot Size |
| LFR |
1 - 25 Hz |
EX, BX |
128 seconds |
| MFDR |
70 - 1700 Hz |
EX, BX |
128 seconds |
| MFR |
25 - 12 KHz |
EX, BZ |
32 seconds |
| HFR |
3.6 KHz - 16 MHz |
EX, EW |
64 seconds |
| HFR |
225 kHz or 325 kHz band |
EX |
about 2.25 seconds |
2048 |
| WBR |
2 MHz or 10 MHz band |
EX |
0.125 second |
4096 |
| LP |
N/A |
Probe |
640 seconds |
The HFR is in a modified "Composite Survey" mode, which now includes
both auto- and cross-correlations for H1, and differs from standard
Survey mode in that its integration constants for H1 and H2 are shorter.
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 20 1 60 25 325k-1.8MHz
H2 1E n n 1 n 10 1 72 200 1.8M-16MHz
Bands ABC require 3.16 sec to complete, H1 requires 1.57 sec, and H2 requires 0.65 sec
for a total of 5.62 sec per sweep. This fits into the 8-second slot allowed for the
normal analysis performed every 64 seconds.