PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 1999-05-14 NOTE = "Information on spectral editing masks" END_OBJECT = TEXT END The TES onboard Data Editor aggregates the spectral data from the six detectors, in order to reduce the total amount of data to be downlinked. Data editing is performed according to the Detector and Spectral Masks specified by the sequence. Detector masks are applied prior to spectral masks. Spectral masks are applied to combine data in the spectral domain. The data from each spectral sample may either be selected/rejected, or averaged with the data from adjacent samples. The selection or average option is determined by a bit in the spectral mask itself. The detectors make up an array three detectors wide by two detectors tall. Detectors are numbered from left to right across the array, starting with 1 in the upper left, ending with 6 in the lower right. Each detector has an associated spectral buffer with the same number. There are two spectral masks associated with the data acquired by the central and peripheral detectors respectively. The center mask is used on spectral buffers 2 and 5, while the periphery mask is used on spectral buffers 1,3,4, and 6. At the end of all additions, each data point is divided by the total number of samples used to generate it. In this division any failed detectors are taken into account so that the final numbers are an average of the data from active detectors only. The spectral data is then scanned and shifted appropriately so that the highest value is represented in a 12 bit wide number (sign bit plus 11 bit mantissa). The amount of shifting is the exponent which is also included in the downlinked packet. Data editing is all done "in-place" with the edited data replacing the original values in the spectral buffers. The TES onboard Data Editor keeps track of the final lengths of the six spectral buffers after editing. TES has 19 spectral masks loaded onboard at all times (residing in PROM). The names of these 19 masks are listed below (the bits are in specmask.tbl). Other spectral masks can be designed on the ground and then loaded on board during regular sequence command uploads. Mask 00 Full_Select Mask 01 Half_Select Mask 02 Third_Select Mask 03 Quarter_Select Mask 04 Eighth_Select Mask 05 Full_Average Mask 06 Half_Average Mask 07 Third_Average Mask 08 Quarter_Average Mask 09 Eighth_Average Mask 10 Half+CO2_Select Mask 11 Third+CO2_Select Mask 12 Quarter+CO2_Select Mask 13 Half+CO2_Average Mask 14 Third+CO2_Average Mask 15 Quarter+CO2_Average Mask 16 Half+H2O+CO2_Select Mask 17 Half+H2O+CO2_Average Mask 18 Polar_Half_Average