PDS_VERSION_ID = PDS3 RECORD_TYPE = "STREAM" RECORD_BYTES = 66 ^SPREADSHEET = "REX_AGCGAINB.CSV" DATA_SET_ID = "NH-X-REX-3-KEMCRUISE1-V2.0" PRODUCT_CREATION_TIME = 2016-06-09T16:39:53 PRODUCT_ID = "NH REX AGC HISTORY DATA - SIDE B" DESCRIPTION = " This document records the Automatic Gain Control (AGC) history for the Radio Science Experiment (REX) instrument, Side B, on-board the New Horizons (NH) spacecraft. " OBJECT = SPREADSHEET NAME = "NH REX AGC HISTORY DATA - SIDE B" FIELD_DELIMITER = "COMMA" FIELDS = 6 ROW_BYTES = 66 ROWS = 211 DESCRIPTION = "This is a SPREADSHEET object composing a table of New Horizons (NH) spacecraft, Radio Science Experiment (REX) instrument, Automatic Gain Control (AGC), Side B state history. The purpose of the table is to provide the gain value setting of the REX instrument current with each observation in order to properly calibrate the observation. 'Current' means the last setting with an MET less than the MET of an observation; for observations before the first entry in this table, use a setting of 167 or 163 for Side A or B, respectively. Refer to the documentation, especially the Science Operations Center (SOC) Instrument Interface Control Document (ICD), files DOCUMENT/SOC_INST_ICD*.*, delivered with this data set, for further details about calibrating REX data. The MET- and UTC-based time values have been truncated to the nearest UTC or spacecraft second, so there will be differences in the time represented by those values of up to a second, but for the purpose of this table they are insignificant. Each ROW in the table records the start time (COLUMNS START_MET [4], START_UTCDOY [5], START_UTCCAL [6]), of a period when the AGC gain setting was set to a specific value (COLUMN GAIN [3]). The end of each period is implicit as the start time of the next row; the last row has no implict end time, but the table will containg updated rows to cover all observations for any data set with which it is delivered. The data in this table have been extracted from ground-based, simulated command logs of NH flight activities. Initial attempts at extracting these data from spacecraft-based housekeeping (HK) telemetry failed because the frequency of downlink of HK telemetry was insufficient to provide adequate time resolution and coverage. The format of the table is Comma-Separated-Value (CSV) lines. Each row in the table will look like the following line, with columns; the legend below the line describes each COLUMN: REX,agcgainX,157,235946203,2013-193T14:44:45,2013-07-12T14:44:45 <+> <--+---> <+> <---+---> <-------+-------> <--------+--------> | | | | | | | | | | | V | | | | | Start time in UTC | | | | | calendar format | | | | V | | | | Start time in UTC Day Of Year format | | | V | | | Start time in MET format | | V | | Gain value | V | AGC gain identifier; always agcgaina or agcgainb V Instrument; always REX " OBJECT = FIELD NAME = "INSTRUMENT_ID" FIELD_NUMBER = 1 BYTES = 3 DATA_TYPE = CHARACTER DESCRIPTION = "The instrument, which will always be REX in this table" END_OBJECT = FIELD OBJECT = FIELD NAME = "GAIN_ID" FIELD_NUMBER = 2 BYTES = 8 DATA_TYPE = CHARACTER DESCRIPTION = "The gain ID indictating to which side of REX this row applies; this will always be agcgainb in this table, indicating this is Side B" END_OBJECT = FIELD OBJECT = FIELD NAME = "GAIN" FIELD_NUMBER = 3 BYTES = 3 DATA_TYPE = ASCII_INTEGER DESCRIPTION = "The Automatic Gain Control (AGC) gain setting for the time period on this row. Refer to the ICD, mentioned in the DESCRIPTION for this SPREADSHEET, for an explanation of this value and how to use it. For a constant rate of accumumlating raw radiometry, each unit increment of this setting represents a decrease in the resulting calibrated power of about half a dBm; as such there is no specific unit applicable to this FIELD. Refer to the ICD for more detail." END_OBJECT = FIELD OBJECT = FIELD NAME = "START_MET" FIELD_NUMBER = 4 BYTES = 10 DATA_TYPE = ASCII_INTEGER DESCRIPTION = "The start Mission Event Time (MET) of the time period on this row. This is the count of the spacecraft clock; refer to the documentation and data set catalog for more information about time. This value has been truncated to the spacecraft second, so there may be an insignificant difference of up to a second between this value and the UTC-based values on the same row." END_OBJECT = FIELD OBJECT = FIELD NAME = "START_UTCDOY" FIELD_NUMBER = 5 BYTES = 17 DATA_TYPE = TIME DESCRIPTION = "The start UTC, at the spacecraft, of the time period on this row, in Day Of Year (DOY) format. This value has been truncated to the UTC second, so there may be an insignificant difference of up to a second between this value and the START_MET on the same row." END_OBJECT = FIELD OBJECT = FIELD NAME = "START_UTCCAL" FIELD_NUMBER = 6 BYTES = 19 DATA_TYPE = TIME DESCRIPTION = "The start UTC, at the spacecraft, of the time period on this row, in calendar format. This value has been truncated to the UTC second, so there may be an insignificant difference of up to a second between this value and the START_MET on the same row." END_OBJECT = FIELD END_OBJECT = SPREADSHEET END