The instrument noise performance is specified as a required noise performance at a specified range of input radiance levels. The ratio between these two quantities is large, implying a large dynamic range.
The instrument is required to perform over a specified range of input radiance. Performance requirements are to be met at nominal input radiances as detailed below.
The instrument performance requirements are stated below are minimum specifications.
The instrument performance is stated on the assumption of filter profiles matching the "square" profiles shown in Table ?.
The transmission outside the passband must be sufficiently small to effectively eliminate instrument radiation, terrestrial radiation and scattered solar radiation. The rejection levels outside the band are TBD.
The average channel performance varies depending upon the channel but all the channels are fairly near the limit of photon statistics for the channel.
Tables Table 7.4 and Table 7.5 list the requirements for the minimal channel set outlined above. The performance requirement is given at the nominal scene radiance (NSR) for both the average and difference channels.
The scene radiance range (SRR) given assumes maximum surface temperatures of about 347K (1.0 emissivity) for the 4.7µm channels and a solar reflectivity of 0.5 with an overhead sun for the 2.3/2.4æm chancels. It is recognised that because of the influence of the actual signal level on the performance that the NER will increase with increasing signal level. The performance is therefore specified at the NSR.