urn:nasa:pds:clementine1_bistatic:data:s21 1.0 1.21.0.0 Product_Observational 2024-05-17 1.0 Product migrated to PDS4 from PDS3. 1994-04-09T18:36:45Z 1994-04-09T18:52:45Z Deep Space Program Science Experiment Mission urn:nasa:pds:context:investigation:mission.deep_space_program_science_experiment data_to_investigation Clementine 1 Clementine 1 Host urn:nasa:pds:context:instrument_host:spacecraft.clem1 is_instrument_host Radio Science Subsystem Instrument urn:nasa:pds:context:instrument:clem1.rss is_instrument Moon Satellite urn:nasa:pds:context:target:satellite.earth.moon data_to_target data_table processing_information_to_data_object STEER 1997-06-09 FND s21.tab 1998-03-19T03:11:07 This file contains double precision complex time samples from the Clementine bistatic radar experiment. These samples cover the observing time when anomalous backscatter from the lunar South Pole would have been most easily detected. This file is the RCP output from the second STEER stage of processing. In this stage sample phases were adjusted to put the frequency of the South Pole echo at the center (12500 Hz) of the passband. The difference between the carrier and Pole frequencies is given by coefficients in the file DF2SCM.TAB in the CALIB directory of this archival data set. HEADER_TABLE 0 1 HEADER_TABLE provides identification of both data and processing. Included are date/time of original experiment; original input file name; DSN antenna used; frequency band; polarization; previous processing program name, version, and run time; time tags for the data and processing; sampling and processing parameters; and a comment field. Columns are not delimited within the table except by their byte boundaries. The defined columns occupy 256 bytes; the remaining 1792 bytes in the record are not defined. 17 2 2048 1 6 1 0 The time at which data acquisition began; the time of the first sample on the original data tape. Given as year, month, day, hour, minute, and second in six 4-byte fields. Time is UTC at the Earth receiving station. 1 24 EXPERIMENT TIME 1 1 SignedMSB4 4 ODR FILE NAME 1 25 ASCII_String 20 The name of the file of Original Data Records (ODR file) assigned at Stanford. File name has the format ydddhhmm.ODR where y is the least significant digit of the year, ddd is the day-of-year, hh is the hour at which data acquisition began, and mm is the minute at which data acquisition began. Suffix ODR may be upper or lower case. File name is left justified in the field; remaining 8 characters are undefinied (often set to ASCII NULL (binary 0)). ANTENNA NUMBER 2 45 SignedMSB4 4 The number of the DSN antenna (or Front End Assembly, FEA). Common values include 14, 43, and 63 (the 70 meter antennas. FREQUENCY BAND 3 49 ASCII_String 4 The frequency band of the original data. Common values include S (S-band, near 2300 MHz) and X (X-band, near 8400 MHz). Single character is left justified in the field ; remaining 3 characters are undefined (often set to ASCII NULL(binary 0)). POLARIZATION 4 53 ASCII_String 4 The polarization of the original data. Common values include R (right-circularly polarized) and L (left-circularly polarized). Single character is left justified in the field; remaining 3 characters are undefined (often set to ASCII NULL(binary 0)). TRANSMIT FREQUENCY 5 57 IEEE754MSBDouble 8 hertz The transmitted frequency at the spacecraft; sometimes entered as an approximate number. If not known at the time of processing, set to 0. PROGRAM 6 65 ASCII_String 16 Name of the program which created this file. Left justified in the field, which is padded with ASCII BLANK characters. VERSION 7 81 ASCII_String 16 Version of the program which created this file. Left justified in the field, which is padded with ASCII BLANK characters. 2 6 1 0 The time at which PROGRAM generated this file. Given as year, month, day, hour, minute, and second in six 4-byte fields. 97 24 PROCESSING TIME 1 1 SignedMSB4 4 REFERENCE TIME 8 121 IEEE754MSBDouble 8 second Reference time for processing. Used by programs which adjust sample frequency/phase so that all files are corrected with respect to the same phase reference. Commonly set to 0 (UTC midnight) in the first processing step; but some succeeding programs may add small offsets. Units are seconds from midnight. START TIME 9 129 IEEE754MSBDouble 8 second Time of the first sample in the first row of DATA_TABLE. Should be very close to EXPERIMENT TIME. Units are seconds from UTC midnight. END TIME 10 137 IEEE754MSBDouble 8 second Time of the first sample in the last row of DATA_TABLE. Units are seconds from UTC midnight. SAMPLING INTERVAL 11 145 IEEE754MSBDouble 8 second Spacing between complex time samples in this file. SCALE FACTOR 12 153 IEEE754MSBDouble 8 A scale factor which should be applied to sample values if end-to-end amplitude preservation is desired. DECIMATION RATIO 13 161 SignedMSB4 4 The factor by which the sampling rate has been reduced in a digital filtering program. Usually a power of two. Set to 1 if there is no bandwidth reduction. FIRST FILTER BIN 14 165 SignedMSB4 4 The number of the first frequency bin saved in a digital filtering program. Set to 1 if there is no bandwidth reduction. Example: If complex time samples are to be digitally filtered in FFTs of size 1024 and the user wants to extract the central quarter of the original passband, then DECIMATION_RATIO = 4 and FIRST_FILTER_BIN = 385 Bins 385-640 represent the central 25 percent of each 1024-point spectrum. RECORD LENGTH 15 169 SignedMSB4 4 byte The size of each record in the file. BITS PER SAMPLE 16 173 SignedMSB4 4 byte The number of bits required to store each sample in the file. Usually 128 for files in FND format. COMMENT 17 193 ASCII_String 80 A user-provided comment at the time PROGRAM was run. DATA_TABLE data_table 2048 187500 DATA_TABLE contains equally-spaced complex time samples from a previous stage of processing. Each row in the table contains 128 double precision complex time samples. The spacing between the last sample in one row and the first sample in the next is the same as between samples in a single row. Entries in HEADER_TABLE define start time, sample spacing, etc. 0 1 2048 1 128 1 0 Complex time samples after processing by PROGRAM. Each item includes a double precision real part and a double precision imaginary part. 1 2048 DATA SAMPLES 1 1 ComplexMSB16 16 s21.lbl 0 PDS3 Original PDS3 label Carriage-Return Line-Feed