IRTS_LAN (IRTS original data set)
IRTS_LAN files contain all the data the IRTS instruments generated. The IRTS_LAN format is same as used in the IRTS operation time. But the current IRTS_LAN files were corrected time, sorted, and concatenated as `one day, one file' after the operation ended. Note that the IRTS_LAN files do not include the attitude data of the IRTS.
FILE LIST
| file name | start time | end time | n_frames |
|---|---|---|---|
| irts_03291759cc.lan | 03/29 18:00:08.040 | 03/29 23:12:38.017 | 17507 |
| irts_03292312cc.lan | 03/29 23:12:40.577 | 03/31 03:35:48.681 | 94387 |
| irts_03310335cc.lan | 03/31 03:35:50.729 | 03/31 23:54:34.666 | 71236 |
| irts_03312358cc.lan | 03/31 23:58:06.122 | 04/02 02:37:25.290 | 89706 |
| irts_04020237cc.lan | 04/02 02:37:26.314 | 04/03 00:28:11.155 | 70445 |
| irts_04030028cc.lan | 04/03 00:28:14.227 | 04/04 00:05:05.796 | 75441 |
| irts_04031330cc.lan | 04/04 00:05:10.404 | 04/05 01:09:23.324 | 78475 |
| irts_04050109cc.lan | 04/05 01:09:24.348 | 04/06 00:38:07.980 | 80520 |
| irts_04060039cc.lan | 04/06 00:39:44.237 | 04/07 00:10:45.597 | 77450 |
| irts_04070010cc.lan | 04/07 00:10:46.621 | 04/07 23:47:41.262 | 80640 |
| irts_04072347cc.lan | 04/07 23:47:43.822 | 04/09 00:54:03.271 | 84861 |
| irts_04090219cc.lan | 04/09 02:19:24.302 | 04/09 22:49:12.752 | 71270 |
| irts_04092249cc.lan | 04/09 22:49:15.312 | 04/11 01:08:57.454 | 92097 |
| irts_04110242cc.lan | 04/11 02:42:47.413 | 04/12 01:39:58.691 | 79341 |
| irts_04120140cc.lan | 04/12 01:40:03.811 | 04/13 00:40:15.186 | 79852 |
| irts_04130040cc.lan | 04/13 00:40:50.002 | 04/14 00:46:01.413 | 78005 |
| irts_04140046cc.lan | 04/14 00:46:05.509 | 04/15 02:22:30.848 | 89677 |
| irts_04150222cc.lan | 04/15 02:22:34.944 | 04/15 23:48:01.703 | 75137 |
| irts_04152348cc.lan | 04/15 23:48:05.799 | 04/17 00:49:32.446 | 84910 |
| irts_04170049cc.lan | 04/17 00:49:36.542 | 04/18 00:57:01.458 | 84306 |
| irts_04180057cc.lan | 04/18 00:57:04.530 | 04/19 00:35:05.219 | 78461 |
| irts_04190035cc.lan | 04/19 00:35:09.315 | 04/20 00:09:09.364 | 82723 |
| irts_04200009cc.lan | 04/20 00:09:12.436 | 04/21 01:05:22.540 | 87503 |
| irts_04210105cc.lan | 04/21 01:05:26.636 | 04/22 00:36:47.964 | 82490 |
| irts_04220036cc.lan | 04/22 00:36:51.037 | 04/23 00:12:43.726 | 82131 |
| irts_04230012cc.lan | 04/23 00:12:47.822 | 04/23 23:51:49.183 | 82990 |
| irts_04232351cc.lan | 04/23 23:51:52.255 | 04/25 00:16:15.924 | 85601 |
| irts_04250016cc.lan | 04/25 00:16:20.020 | 04/25 16:38:35.394 | 55428 |
| irts_04260747cc.lan | 04/26 07:47:43.748 | 04/26 16:06:32.616 | 11750 |
FORMAT
========================================================================
IRTS_LAN Format by T. Onaka Nov. 1, 1994
(1) Primary header:
Format Item # of Byte comments
A8 file category 8 "IRTS_LAN" to designate IRTS_LAN file
A24 original file 24 indicates the sfdu file from which
this file is created (see below).
A18 time(start) 18 same format as 'time' in sfdu-file
A18 time(end) 18 same format as 'time' in sfdu-file
I10 TI(start) 10 Time code of IRTS frame
A1 Parity(start) 1 indicates even/odd frame (see below)
I10 TI(end) 10 Time code of IRTS frame
A1 Parity(end) 1 see below
I10 FCN(start) 10 Frame counter (see below)
I10 FCN(end) 10 Frame counter (see below)
I6 Block number 6 Number of secondary headers
A4 spare 4 Spare (Last byte is Line Feed)
(0A in HEX)
Note: The naming method of the original sfdu file is not yet fixed, but
should be less than 30 bytes. The remaining bytes are left for
future use in case that we need further information. The details
of these 30 bytes will be fixed later.
Parity is defined as:
'-' for the start parity, if the first frame is an odd frame.
' ' for the start parity, if the first frame is an even frame
and for the end partity, if the last frame is an odd frame.
'+' for the end parity, if the last frame is an even frame.
'*' indicates no TI defined because of the frame drop or so.
in standby mode, no TI is available and this part is left as blank.
This notation indicates whether the time code of the data set
in question is clipped in between the even and odd frames or not.
Frame counter may be used for the check of continuity, although
it will be reset when the telemetry rate is changed.
(2) Secondary header:
Format Item # of Byte comments
A18 time(start) 18 same format as 'time' in sfdu-file
A18 time(end) 18 same format as 'time' in sfdu-file
I10 TI(start) 10 Time code of IRTS frame
A1 Parity(start) 1 indicates even/odd frame (see above)
I10 TI(end) 10 Time code of IRTS frame
A1 Parity(end) 1 see above
I10 FCN(start) 10 Frame counter (see below)
I10 FCN(end) 10 Frame counter
I10 # of frames 10
I2 telemetry rate 2 0 for 6K, 1 for 3K, 2, for standby,
and 3 for else (should not occur).
A6 spare 6 spare (Last byte is LF)
Frame counter should be reset at the beginning of the change of
telemetry rate. The start FCN, then, could tell us if there is any frame
drop during the rate change.
Thus, the total lengths of headers are:
Primary header : 120 bytes
Secondary header: 96 bytes
(3) The data:
In the 6K mode,
struct {
char time[18]; /* Experiment Data Time */
char IRT_DATA[768] /* IRTS data */
char dummy[6] /* dummy */
}
In the 3K mode
struct {
char time[18]; /* Experiment Data Time */
char IRT_DATA[384] /* IRTS data */
char dummy[6] /* dummy */
}
In the standby mode
struct {
char time[18]; /* Experiment Data Time */
char IRT_DATA[48] /* IRTS data */
char dummy[6] /* dummy */
}
Therefore, the lengths of one frames are:
792 bytes for the 6K mode
408 bytes for the 3K mode
72 bytes for the standby mode
(4) The data structure:
The data structure is the same as the one Nakagawa-san
proposed a few weeks ago:
Primary header, Secondary header, Data, Secondary header, Data,....
Note: TIME format (18 characters) was changed when the time correction was performed.
old: 95/04/01 12:34:56^@ note: `^@' = null code (0x00)
new: 04/01 12:34:56.789
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Last modified: Sep 30, 1997