PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM INSTRUMENT_HOST_NAME = "CASSINI ORBITER" INSTRUMENT_NAME = "CASSINI RADAR" OBJECT = TEXT PUBLICATION_DATE = 2007-12-19 NOTE = "Description of Volume CORADR_0116" END_OBJECT = TEXT END Volume CORADR_0116: Rings, Sequence S27, January 27, 2007 1. Introduction This volume contains Cassini Radar Burst Order Data Products (BODP) and, if applicable, Basic Image Data Record (BIDR) products for a single observation (data take). Each product contains the results from processing of the Cassini Radar instrument in passive (radiometer) and/or active (scatterometer, altimeter, synthetic aperture radar) modes. A given observation may contain data for only a subset of these modes. The volume also contains product documentation and the set of antenna pattern beam files and processing parameters that were used for these products. The products on this volume are the exact products released by the Cassini Project. Supporting documentation and labels conform to the Planetary Data System (PDS) Standards Reference, Version 3.6, Jet Propulsion Laboratory (JPL) Document D-7669, Part 2, August 1, 2003; and the Planetary Science Data Dictionary Document, Jet Propulsion Laboratory (JPL) Document D-7116, Rev. E, August 28, 2002, Online Update Version pdscat1r57, April 25, 2005. The most recent copies of both documents are available at the PDS web site, http://pds.jpl.nasa.gov . For more information about the volume directory structure, refer to the Volume Software Interface Specification for Cassini Radar Instrument Team Data Products, JPL D-27890. A copy of the document is located on this volume as file VOLSIS.PDF in the DOCUMENT directory. 2. Disk Format Not applicable, as these products are being delivered to PDS electronically. Each volume, however, has been constrained to a maximum size of 4.3 GB so that it can fit on a single DVD-R disc. 3. File Formats Science Data File Format Four types of BODP science data files have been defined. Short Burst Data Record (SBDR) Product Instrument telemetry and calibrated science data in burst order Long Burst Data Record (LBDR) Product Instrument telemetry, calibrated science data, and time-sampled echo data in burst order; only includes records for which radar was in active mode (scatterometer, altimeter, synthetic aperture radar) Altimetry Burst Data Record (ABDR) Product Instrument telemetry, calibrated science data, and altimeter profile data in burst order; only includes records for which radar was in altimeter mode Altimetry Burst Data Record Summary (ABDR-SUMMARY) Product Surface height and related measurements derived from the average of all pulses in a burst, in burst order; only includes records for which radar was in altimeter mode The SBDR product should be available for all observations. LBDR products will not be available if no active-mode data was collected, and ABDR and ABDR-SUMMARY products will only be available if altimetry data was collected. The Cassini BODP science data files are formatted using the "table object" structure of the PDS standards. Each row of the table consists of a data record comprising radar and ancillary data for a single burst. Rows occur in time order. A column represents a particular data field with a specific meaning and data type (i.e. integer, real, etc.) Real values are either 32-bit or 64-bit IEEE floating-point values with little endian byte order (PC_REAL). Cassini BIDR products result from the processing of synthetic aperture radar (SAR) data into imagery (sigma_0 backscatter), incidence angle, and related products. The Cassini BIDR science data files are formatted using the "image object" structure of the PDS standards. The size and coordinate system of the image is defined in the attached PDS label. Image pixels may have several different meanings and data types. To conserve space, each ABDR, LBDR and BIDR product on this volume has been compressed with the ZIP utility and stored in its own archive with the extension ".ZIP". Use the UNZIP utility to extract the original product file from a ZIP archive. The source code for ZIP and UNZIP is publicly available, but both utilities come pre-installed on many types of Unix and Linux systems as the commands "zip" and "unzip," respectively. On those systems, the command-line syntax for extracting a file with "unzip" is unzip file.ZIP -d output_directory where "file.ZIP" is the ZIP archive and "output_directory" is the name of the directory into which the uncompressed product will be written. The output directory must be writable by the user and be located on a file system with sufficient free space to hold the uncompressed product. The command unzip -l file.ZIP will list the name and uncompressed file size (in bytes) of the file stored in archive "file.ZIP." The uncompressed file size is also stored as the value of REQUIRED_STORAGE_BYTES in the ZIP archive's detached label, which is located in the same directory as the ZIP archive on the volume. For more information about the format and content of the BODP files, refer to the Cassini Radar Burst Ordered Data Product Software Interface Specification, JPL Document D-27891. A copy of the document is located on this volume as file BODPSIS.PDF in the DOCUMENT directory. For more information about the format and content of the BIDR files, refer to the Cassini Radar Basic Image Data Record Software Interface Specification, JPL D-27889. A copy of the document is located on this volume as file BIDRSIS.PDF in the DOCUMENT directory. For a pointer to more information about the ZIP/UNZIP utilities, refer to the software catalog SOFTWARE.CAT in the CATALOG directory on this volume. Document File Format Document files with the .TXT suffix exist in the root, CALIB, CATALOG, DOCUMENT, EXTRAS, INDEX, and SOFTWARE directories and their subdirectories. These files are ASCII files with attached PDS labels and with line lengths that do not exceed 80 characters. Document files have variable-length lines with an end-of-line designator consisting of a carriage-return character followed by a linefeed character. This allows the files to be read by the MacOS, Microsoft Windows, and Unix operating systems. Tabular File Format A tabular file (INDEX.TAB) exists in the INDEX directory. This file is an ASCII file formatted for direct reading into many database management systems on various computers. Commas separate all fields, and character fields are enclosed in double quotation marks ("). Character fields are left justified and padded on the right with spaces to keep quotation marks in the same columns of successive records. Number fields are right justified and padded with spaces on the left to keep fixed-width fields. The records are of fixed length, and the last two bytes of each record contain the ASCII carriage-return and line-feed character. This allows a table to be treated as a fixed length record file on computers that support this file type and as a text file with embedded line delimiters on those that don't. A detached PDS label describes INDEX.TAB. The PDS label file name is the same as the tabular file but with the extension ".LBL". PDS Label Format All data files in the Cassini Radar Instrument Team Archive Collection have PDS labels. A PDS label, whether attached to or detached from its associated file, provides descriptive information about the associated file. The PDS label is an object-oriented structure consisting of sets of "keyword = value" declarations. The object to which the label refers (e.g. IMAGE, TABLE, etc.) denotes the form: ^object = location in which the caret character (^, also called a pointer in this context) indicates where to find the object. In an attached label, the location is an integer representing the starting record number of the object (the first record in the file is record 1). In a detached label, the location denotes the name of the file containing the object, along with the starting record or byte number, if there is more than one object in the file. For example: ^HEADER = ("F01.IMG",1) ^IMAGE = ("F01.IMG",1025 ) indicates that the IMAGE object begins at byte 1025 of the file F01.IMG, in the same directory as the detached label file. Below is a list of the possible formats for the ^object definition. ^object = n ^object = n ^object = "filename.ext" ^object = ("filename.ext",n) ^object = ("[dirlist]filename.ext",n) ^object = ("filename.ext",n) ^object = ("[dirlist]filename.ext",n) where: "n" is the starting record or byte number of the object, counting from the beginning of the file (record 1, byte 1), "" indicates that the number given is in units of bytes, "filename" is the up to 27-character, alphanumeric upper-case file name, "ext" is the 3 character upper-case file extension, "[dirlist]" is a period-delimited path-list of parent directories, in upper case, that specifies the object file directory (used only when the object is not in the same directory as the label file). The list begins at the directory level below the root directory of the CDROM. "[dirlist]" may be omitted when the object being described is located in the same directory as the detached label. Detached label files have variable length lines with an end-of-line designator consisting of a carriage-return character followed by a line-feed character. This allows the files to be read by the MacOS, Microsoft Windows, and Unix operating Systems. Catalog File Format Catalog files (suffix.CAT) exist in the root and CATALOG directories. They are formatted in an object-oriented structure consisting of sets of "keyword = value" declarations. 4. Volume Contents The files in this volume are organized in one top-level directory with several subdirectories. The following outline shows the structure and content of these directories. In the table, directory names are enclosed in square brackets ([]), upper-case letters indicate an actual directory or file name, and lower-case letters indicate the general form of a set of directory or file names. FILE/DIRECTORY DESCRIPTION Top-level directory | |- AAREADME.TXT Describes volume contents, organization and disk | use (this file). | |- ERRATA.TXT Cumulative listing of known errors and anomalies in | the volumes. | |- VOLDESC.CAT Description of the contents of this volume. | |- [INDEX] Contains index tables for the data products on | | this disk. | | | |- INDXINFO.TXT Description of the contents of this directory. | | | |- INDEX.TAB Index table file for Cassini Radar Instrument Team | | data products. | | | |- INDEX.LBL Detached label file describing contents of INDEX.TAB. | |- [DOCUMENT] Contains various documents that facilitate | | the understanding of the datasets included | | on this volume. | | | |- DOCINFO.TXT Description of the contents of this | | directory. | | | |- BODPSIS.PDF PDF version of the BODP (Burst Ordered Data | | Products) SIS. | | | |- BODPSIS.HTML HTML version of the BODP SIS. | | | |- BODPSIS.CSS Cascading Style Sheet for the HTML version | | of the BODP SIS. | | | |- BODPSIS.LBL Detached label describing the files that | | comprise the BODP SIS. | | | |- BIDRSIS.PDF PDF version of the BIDR (Basic Image Data | | Records) SIS. | | | |- BIDRSIS.HTML HTML version of the BIDR SIS. | | | |- BIDRSIS_FIGnn.GIF Embedded figures for BIDRSIS.HTML, where nn | | is the 2-digit figure number. | | | |- BIDRSIS.CSS Cascading Style Sheet for the HTML version | | of the BIDR SIS. | | | |- BIDRSIS.LBL Detached label describing the files that | | comprise the BIDR SIS. | | | |- VOLSIS.PDF PDF version of the Volume SIS. | | | |- VOLSIS.HTML HTML version of the Volume SIS. | | | |- VOLSIS.CSS Cascading Style Sheet for the HTML version | | of the Volume SIS. | | | |- VOLSIS.LBL Detached label describing the files that | comprise the Volume SIS. | |- [CATALOG] This directory contains the catalog files. | | | |- CATINFO.TXT Description of the contents of this directory. | | | |- ABDRDS.CAT Information about the ABDR data sets. | | If no altimetry data was collected during the | | observation, then this catalog will not be | | present on the volume. | | | |- ABDRSUMDS.CAT Information about the ABDR-SUMMARY data sets. | | If no altimetry data was collected during the | | observation, then this catalog will not be | | present on the volume. | | | |- BIDRDS.CAT Information about the BIDR data sets. | | If no SAR data was collected during the | | observation, then this catalog will not be | | present on the volume. | | | |- DSMAP.CAT Information about the map projection used for | | the BIDR products; includes definition of oblique | | cylindrical projection. | | | |- INST.CAT Information about the Cassini radar instrument. | | | |- INSTHOST.CAT Information about the Cassini spacecraft. | | | |- LBDRDS.CAT Information about the LBDR data sets. | | If no active-mode data was collected during the | | observation, then this catalog will not be | | present on the volume. | | | |- MISSION.CAT Information about the Cassini mission. | | | |- PERSON.CAT Information about Cassini team members responsible | | for generating the radar products. | | | |- PROJREF.CAT Cassini Project references mentioned in other | | catalog files. | | | |- REF.CAT Cassini Radar references mentioned in other catalog | | files. | | | |- SBDRDS.CAT Information about the SBDR data sets. | | | |- SOFTWARE.CAT Information about software that is necessary or | helpful in accessing or processing the data on | this volume. | |- [DATA] This directory contains the data products, organized | | into subdirectories by product type. | | | |- [ABDR] Directory containing ABDR data product files. | | | If no altimetry data was collected during the | | | observation, then this directory will not be | | | present on the volume. | | | | | |- ABDR_yy_Dzzz_Vnn.ZIP ZIP-compressed ABDR product file, | | | where | | | yy = Radar mode of data | | | zzz = 3-digit radar observation counter | | | nn = 2-digit version number | | | | | |- ABDR_yy_Dzzz_Vnn.LBL Detached label for ABDR_yy_Dzzz_Vnn.ZIP | | | | | |- ABDR.FMT Format file for the ABDR_TABLE object | | referenced in the attached label for | | an Altimeter Burst Data Record product. | | | |- [ABDR_SUMMARY] Directory containing ABDR-SUMMARY data product | | | files. If no altimetry data was collected during | | | the observation, then this directory will not be | | | present on the volume. | | | | | |- ABDR_SUMMARY_yy_Dzzz_Vnn.CSV | | | ABDR-SUMMARY product file, | | | where | | | yy = Radar mode of data | | | zzz = 3-digit radar observation counter | | | nn = 2-digit version number | | | | | |- ABDR_SUMMARY_yy_Dzzz_Vnn.LBL | | | Detached label for ABDR_SUMMARY_yy_Dzzz_Vnn.CSV | | | |- [LBDR] Directory containing LBDR data product files. | | | If no active-mode data was collected during the | | | observation, then this directory will not be | | | present on the volume. | | | | | |- LBDR_yy_Dzzz_Vnn.ZIP ZIP-compressed LBDR product file, | | | where | | | yy = Radar mode of data | | | zzz = 3-digit radar observation counter | | | nn = 2-digit version number | | | | | |- LBDR_yy_Dzzz_Vnn.LBL Detached label for LBDR_yy_Dzzz_Vnn.ZIP | | | | | |- LBDR.FMT Format file for the LBDR_TABLE object | | referenced in the attached label for | | a Long Burst Data Record product. | | | |- [SBDR] Directory containing SBDR data product files. | | | | | |- SBDR_yy_Dzzz_Vnn.TAB SBDR product file, where | | | yy = Radar mode of data | | | zzz = 3-digit radar observation counter | | | nn = 2-digit version number | | | | | |- SBDR.FMT Format file for the SBDR_TABLE object | | referenced in the attached label for | | a Short Burst Data Record product. | | | |- [BIDR] Directory containing BIDR data product files. | | If no SAR data was collected during the | | observation, then this directory will not be | | present on the volume. | | | |- BIbcdeefggg_Dhhh_Tiii_Vnn.ZIP Zip-compressed BIDR product | | file, where | | b = Kind and bit-type of data: | | F = Primary dataset (incidence- | | angle-corrected sigma0) in | | 32-bit floating-point format | | (linear scale, not dB) | | B = Primary dataset in unsigned | | byte format (dB, normalized | | to [0, 255]) | | U = Sigma0 without incidence angle | | correction in 32-bit floating- | | point format (linear scale, | | not dB) | | E = Incidence angle map, 32-bit | | floating-point values in degrees | | T = Latitude map, 32-bit floating- | | point values in degrees | | N = Longitude map, 32-bit floating- | | point values in degrees | | M = Beam mask map, 8-bit unsigned | | byte values | | L = Number of looks map, 32-bit | | integer values | | c = Map projection: | | Q = Oblique cylindrical | | d = Map resolution: | | B = 2 pixels/degree | | D = 8 pixels/degree | | F = 32 pixels/degree | | H = 128 pixels/degree | | I = 256 pixels/degree | | ee = Absolute value of latitude at | | center of file, rounded to | | nearest degree | | f = Hemisphere of center of file: | | N = Northern | | S = Southern | | ggg = West longitude at center of | | file, rounded to nearest degree | | hhh = 3-digit data take ID | | (observation counter) from which | | data are included, left-padded | | with zeroes as needed | | iii = 3-digit index of Titan flyby | | from which data are included, | | left-padded with zeroes as | | needed. (Note: the index | | for the "Ta" flyby is "00A") | | nn = 2-digit version number | | | |- BIbcdeefggg_Dhhh_Tiii_Vnn.LBL Detached label for | BIbcdeefggg_Dhhh_Tiii_Vnn.ZIP | |- [CALIB] This directory contains files that were used to | | calibrate the Cassini radar data. | | | |- CALINFO.TXT Description of the contents of this directory. | | | |- [BEAMPAT] Directory containing antenna gain pattern files | | | for each beam and documentation for those files. | | | | | |- PATINFO.TXT Description of the contents of this directory. | | | | | |- BEAMx_Vnn.PAT Antenna gain pattern file, where | | | x = Beam number (1 to 5) | | | nn = 2-digit version number | | | | | |- BEAMx_Vnn.LBL Detached label for BEAMx_Vnn.PAT. | | | |- [CONFIG] Directory containing processor configuration files | | and documentation for those files. | | | |- CFGINFO.TXT Description of the contents of this | | directory. | | | |- PCF_yyyy_Vnn.CFG Processor configuration file for this | | observation, where | | yyyy = 4-digit radar observation counter | | nn = 2-digit version number | | | |- PCF_yyyy_Vnn.LBL Detached label for PCF_yyyy_Vnn.CFG. | |- [EXTRAS] This directory contains files that do not fit anywhere | | else. A Cassini Radar Transition file should be present | | for each observation. The directory may also contain | | memorandums, plots, or analyses pertinent to the data | | products being delivered. | | | |- CRT_yyy_Vnn.TAB Cassini Radar Transition file, where | | yyy = 3-digit radar observation counter | | nn = 2-digit version number | | | |- xx_SEQUENCE_DESIGN_MEMO.PDF Memorandum (in PDF format) describing | command sequence design for | observation, where | xx = Observation ID (e.g., "TA"), | expressed as a combination of | either two or three upper-case | letters and/or numerals. | |- [SOFTWARE] This directory contains information about software | applications that are necessary or helpful in | accessing or processing the data products on this | volume. | |- SOFTINFO.TXT Description of the contents of this directory, including information on where to obtain the software that was used to compress the LBDR and (if present) the BIDR data products on this volume. 5. Recommended DVD Drives and Driver Software Not applicable for electronic delivery. 6. Errata and Disclaimer A list of anomalies and errors is maintained in the file ERRATA.TXT at the root directory of this volume. Although considerable care has gone into making this volume, errors are both possible and likely. Users of the data are advised to exercise the same caution as they would when dealing with any other unknown data set. Reports of errors or difficulties would be appreciated. Please contact one of the persons listed herein. 7. Contact Information For questions concerning this volume set, data products, and documentation, contact Philip S. Callahan Jet Propulsion Laboratory M/S 300-319 4800 Oak Grove Drive Pasadena, CA 91109-8099 USA Phone: +1 818-354-4753 E-mail: Philip.S.Callahan@jpl.nasa.gov Bryan W. Stiles Jet Propulsion Laboratory M/S 300-319 4800 Oak Grove Drive Pasadena, CA 91109-8099 USA Phone: +1 818-354-5329 E-mail: Bryan.W.Stiles@jpl.nasa.gov For questions concerning PDS standards and usage, contact Patricia A. Garcia United States Geological Survey 2255 North Gemini Drive Flagstaff, AZ 86001 Phone: (928) 556-7246 E-mail: pgarcia@usgs.gov