PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT INTERCHANGE_FORMAT = ASCII PUBLICATION_DATE = 2002-05-01 NOTE = "N/A" END_OBJECT = TEXT END PROJECT CASSINI NUMBER: DORS-002 SOFTWARE INTERFACE SPECIFICATION REVISION: Revision 1 COVER SHEET DATE: May 1, 2002 SIS NAME: Media Calibration System (MCS) Path Delay File PURPOSE: Defines the format for the MCS path delay file to be delivered by IO-RS to the RST as part of each experiment data package. DATA FLOW: FROM TO DATA OBJECT MEDIUM IO-RS RST ASCII File Electronic File APPLICABLE DOCUMENTS: See below for description. Related OIA: OIA-DOI-012 SIS COORDINATOR: R G Herrera APPROVAL NAME DATE GDSE T. Sesplaukis_______________________ _______________ IO-RS/OTL R. Herrera _______________________ _______________ RST TL: A. Kliore _______________________ _______________ IO Mgr J. Clark _______________________ _______________ Software Interface Specification (SIS) Name: Media Calibration System Path Delay File Revision Date: 05-01-02 Revision 1 Module Title: Media Calibration System (MCS) Path Delay File Purpose: This SIS module describes contents and structure of the Advanced Media Calibration path delay file. Data Flow: From To Data Object Physical Medium IO-RS RST ASCII file DVD-R Module Preparer: R G Herrera RST TL: IO-RS OTL: L3 SE: MCS Path Delay File Document Log Date Page No. Status 11-09-01 All Original 05-01-02 iii,1,5 Revision 1 List of TBD Items Page Section Item None MCS Path Delay File Distribution Asmar, S. 264-860 Barbinis, E. 264-860 Fleischman, D. 264-860 Goltz, G. 264-860 Herrera, RG 264-860 Kliore, A. 161-260 Rappaport, N. 301-150 Sesplaukis, T. 230-260 Wait, D. 230-260 Section 1 - General Description 1.1 Purpose of Document This Software Interface Specification (SIS) describes the contents and structure of the Advanced Media Calibration path delay file. This ASCII file contains pointing information, path delay, and various quality flags. Path delay estimates in this file correspond directly to data records in the merged observables file that share a common timetag. 1.2 Scope This is a Cassini SIS module. 1.3 Applicable Documents None 1.4 Functional Description 1.4.1 Data Source, Destinations, and Transfer Method The path delay file will be created as the end-product of post-pass processing of the raw MCS data. The file will be delivered to the Radio Science Team along with the other ancillary and calibration data files on a DVD-R. 1.4.2 Pertinent Relationships with Other Interfaces None. 1.4.3 Labeling and Identification The filename will have the following convention: SSSTTAAyyyy_ddd_hhmm_hhmmrr.PDx Where: SSS = Sequence/Orbit number (e.g., C29) TT = target (e.g., "EA" for Earth) AA = activity (e.g., "GW" for Gravitational Wave Experiment) yyyy = year ddd = day of year hhmm_hhmm = start & stop time of data in this file (hhmm) rr = receiving station PD = abbreviation for "Path Delay" x = system ID (i.e., "1" or "2") 1.4.4 Assumptions and Constraints N/A Section 2 - Environment 2.1 Hardware Characteristics and Limitations N/A 2.2 Interface Medium and Characteristics This interface shall consist of an ASCII file. 2.3 Input/Output Protocols 2.3.1 Device Addressing N/A 2.3.2 Operating System Protocols N/A 2.3.3 Deformatting N/A 2.3.4 Calling Sequence Any simple text editor can be used to view the path delay file. 2.4 Failure Protection, Detection, and Recovery Features N/A 2.5 End-Of-File Convention The end-of-file shall be denoted by the physical end-of-file. 2.6 Utility Programs N/A Section 3 - Data Flow Characteristics 3.1 Operational Characteristics 3.1.1 Generation Method and Frequency The path delay file is generated by IO-RS using software supplied by the development team for the Cassini Advanced Media Calibration System. Typically, the file is generated a week after data acquisition when the MCS development team has supplied updated calibration files. 3.1.2 Time Span of Product Each path delay file shall span one tracking pass. 3.2 Data Volume The size of the path delay file is dependent on the length of the tracking pass during which media calibration data was acquired. A typical file will be about 1.3 Mbytes. 3.3 Flow Rate N/A 3.4 Access Privileges N/A Section 4 - Detailed Data Object Definition 4.1 Structure and Organization Overview This section describes the content of the path delay file. 4.2 Data Format and Definition 4.2.1 SFDU Header The path delay file does not contain an SFDU header. 4.2.2 Header description All header lines begin with '#' as the first character on each line. To make the path delay file accessible to data users, the file header contains a key explaining the content of all data fields and the meaning of all data quality flag (see example in Section 4.2.3 below). The path delay file also contains the following identifiers: #EXCLUDED_CHANNELS List of channels that were excluded from the retrieval algorithm because of "out of range" performance. (Bayesian only) #COMMENT Embedded operator comments from the psX.cfg processing configuration file #VER_PD Current level 2 file format version number 4.2.3 Data record description P where: epoch time seconds since 00:00 Jan 1, 1970 (UT) az Advanced Water Vapor Radiometer (AWVR) azimuthal position (deg) el AWVR elevation position (deg) wpd Zenith wet path delay (cm) dpd Zenith dry (static) path delay (cm) liq Cloud liquid (microns) algid Statistical retrieval ID cldflg Cloud flag wvrflg AWVR flag mtpflg Microwave Temperature Profiler (MTP) flag smflg Surfmet flag windflg Wind flag pdflg Path delay flag 4.2.4 Data record numerical format "P I10 F8.3 F8.3 F8.3 F8.3 F6.0 I3 I1 I1 I1 I1 I1 I1" 4.2.5 Notes The path delay file is created by the path delay retrieval programs written by the MCS Development Team. The file is read by the data visualization program called MCSView. The path delay file data content is directly derived from the merged observables file on which it is based; i.e., for every data record of observables in the Level 1a file, there exists a retrieved path delay data record in the path delay data file. Retrieval ID Retrieval type Conditions 001 Statistical all weather algorithm (all channels) 002 Statistical uses AWVR and Surface Meteorology (SM) channels only 003 Statistical uses AWVR and MTP channels only 004 Statistical uses AWVR channels only 005 Statistical uses AWVR 23.8 and 31.4 GHz channels only 006 Statistical uses AWVR 22.2 and 31.4 GHz channels only 200 Bayesian excluded channels are listed in the header 4.2.6 Path delay file example # Path delay data file # Header lines start with "#" # Data lines start with "P" # # Fields in "P" lines are: # Time in sec since 0000 UT of 1/1/1970 # az in deg. # el in deg. # wet pdzen in cm # dry pdzen in cm # cloud liq. in microns # alg_id # cloud_flag # wvr_flag # mtp_flag # surf_flag # wind_flag # pd_flag # # Algorithm IDs are: # 001 statistical, all weather algorithm (all instrument channels) # 002 statistical, uses only AWVR and SM channels # 003 statistical, uses only AWVR and MTP channels # 004 statistical, uses only AWVR channels # 005 statistical, uses only AWVR 23.8 and 31.4 GHz channels # 006 statistical, uses only AWVR 22.2 and 31.4 GHz channels # 200 bayesian, excluded channels are listed under "EXCLUDED CHANNELS" # # Flag positions are: # cloud_flag = 0 => liquid water is less than 20 microns # cloud_flag = 1 => liquid water is between 20 and 100 microns # cloud_flag = 2 => liquid water is between 100 and 200 microns # cloud_flag = 3 => liquid water is greater than 200 microns # (if the cloud_flag is >=3 and the bayesian is run, a value of 999 # will appear as a path delay in lieu of an actual retrieved value # # wvr_flag = 0 => All AWVR observables within acceptable range # wvr_flag = 1 => AWVR observable(s) outside acceptable range # mtp_flag = 0 => All MTP observables within acceptable range # mtp_flag = 1 => MTP observable(s) outside acceptable range # surf_flag = 0 => All Surfmet observables within acceptable range # surf_flag = 1 => Surfmet observable(s) outside acceptable range # wind_flag = 0 => Wind observables are within acceptable range # wind_flag = 1 => Wind observable(s) outside acceptable range # pd_flag = 0 => Retrieved zenith path delay in acceptable range # pd_flag = 1 => Retrieved zen. path delay outside acceptable range # pd_flag = 2 => Elevation lies outside of prescribed range. If the # bayesian retrieval is running (algid=200), no retrieval is performed. # If the stat algorithm is running, the retrieval is performed, but may # be erroneous due to ground pickup. # EXCLUDED_CHANNELS NONE # PD_VER 3 # ELMIN 95.00 # ELMAX 105.00 # time az el wetdly drydly cloud alg f f f f f f P 1007514060 69.211 103.188 2.823 206.218 0. 200 0 0 0 0 0 0 P 1007514084 73.420 91.252 999.990 206.218 0. 200 0 0 0 0 0 2