Document title: Description of ISIS 2 FULL and AVERAGE ionogram file format Project: ISIS NDADS Datatypes: ISIS2_TOPS_FULL_24S_OS2BIN ISIS2_TOPS_AVG_24S_OS2BIN ISIS2_TOPS_AVG_24S_CDF ISIS2_TOPS ISIS2_CDF Super-EID: DOCUMENTS There may be other documents also identified by this super-EID. NDADS filename: ISIS2_IONOGRAM_FORMAT.DOC TRF entry: b46764.txt in NSSDC's controlled digital document library, Mar. 1998. Document text follows: ---------------------- Description of ISIS 2 FULL and AVERAGE ionogram file format ----------------------------------------------------------- Items starting with "Satellite ID number" and ending with "Scan Line Number of Start of Swept Portion" are all contained in the first record. Each entry after that is a separate record. Each record is preceded and followed by a 4 byte descriptor that contains the length of the record. For example the first record is 160 bytes in length. Therefore to get the entire record you would have to allow for 168 bytes (4+160+4). The "Types" of data are I*1 (1 byte integer), I*4 (4 byte integer), R*4 (4 byte real) and R*8 (8 byte real). Any value for the below variables found to be outside the valid value for that variable indicates the variable was undetermined. Description of Variable Type Comments ------------------------------------------------------------------- Satellite ID number (One Digit ID) I*4 (1:AL1,2:AL2,3:IS1,4:IS2) Station Code number (Two Digit Code) I*4 Transmitter Power Code I*4 (1:400W(PRI),2:400W(SEC)) Sounder/Receiver Code I*4 (0:OFF,1:ON) Swept Freq. Range Code I*4 (0:NORMAL,1:EXTENDED) DMODE Code I*4 (0:OFF,1:ON) GMODE Code I*4 (0:OFF,1:ON) Sounder Mixed Mode I*4 (0:OFF,1:ON) AIT Mode I*4 (0:OFF,1:ON) Fixed Freq. Code (Freq of Fixed Freq (MHz)) I*4 (0:OFF,1:0.25,2:0.48,3:1.00, 4:1.95,5:4.00,6:9.303) Year (Last 2 Digits) I*4 Frame Sync UT Day of Year I*4 Frame Sync UT Hour I*4 Frame Sync UT Minute I*4 Frame Sync UT Second (to the microsecond) R*8 Frame Sync UT LMT (HH) I*4 At time of Frame Sync LMT (MM) I*4 At time of Frame Sync GGLatitude (Deg) R*4 At time of Frame Sync GGLongitude (Deg) R*4 At time of Frame Sync Height (km) R*4 At time of Frame Sync GMLTM (HH) I*4 At time of Frame Sync GMLTM (MM) I*4 At time of Frame Sync GMLAT (Deg) R*4 At time of Frame Sync GMLONG (Deg) R*4 At time of Frame Sync Gyro Frequency (MHz) R*4 At time of Frame Sync Invariant Latitude (Deg) R*4 At time of Frame Sync Dip (Deg) I*4 At time of Frame Sync CHI (Deg) I*4 At time of Frame Sync Sunlight I*4 (1:SL,2:NSL) L Shell R*4 At time of Frame Sync C.E.P. I*4 (0:OFF,1:ON) VLF Rcvr. I*4 (0:OFF,1:ON) R.P.A. I*4 (0:OFF,1:ON) I.M.S. I*4 (0:OFF,1:ON) S.P.S. I*4 (0:OFF,1:ON) E.P.D. I*4 (0:OFF,1:ON) Red. Line Phot. I*4 (0:OFF,1:ON) Aur. Scan. Phot. I*4 (0:OFF,1:ON) Scan Line Number of Start of Swept Portion I*4 1st Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 2nd Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 3rd Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 4th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 5th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 6th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 7th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 8th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 9th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 10th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 11th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 12th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 13th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 14th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 15th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 16th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 17th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 18th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 19th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 20th Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 21st Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) 22nd Freq. Marker: Frequency (MHz) Time (ms) R*8,R*8 (ms after Frame Sync) Number of Columns[#C] Number of Rows[#R] I*4,I*4 Dimensions of Arrays and Matrix that follow (for non- average ionogram the Delay Time(R1); where R1=1,#R (in ms) R*8 number of rows fixed Apparant Range(R1); where R1=1,#R (in km) R*8 at 892; average fixed at 223) The next record is repeated #C times (ie; C1=1,#C) Time(C1) Freq(C1) Amplitude(R1,C1) R*8,R*8,I*1 (in ms) (in MHz) (where R1=1,#R)