A Study on the Signal Characteristic Scale of SatelliteOcean Color Remote Sensing
卫星海洋水色遥感信息特征量的研究

The ocean color satellite is mainly used to observe the water content, such as chlorophyll, suspended material and yellow substance. The total radiance arrived et the sensor in the space is divided by the solar radiation as normalized albedo and coded to send back to the ground station. The ocean color are generally detemined by water content. They are monitored by measuring the water leaving radiation from ocean surface, which is a very small part of the total radiation received by the sensor. The most radiance is from atmospheric path and sun reflection of water surface. The radiation ratio of signal to noise from atmosphere etc. e. g. the ratio of the water leaving radiance to noise radiance, is characterized by the possibility of extracting the water color signals. It the paper, the signal characteristic scale (SCS) -normalized albedo and the radiation ratio of signal to noise have been firstly discussed, based on the mechanisms of the satellite ocean color remote sensing. For the radiation transfer of the ocean-atmosphere system, the transport of solar radiation is separated into various processes, such as the molecular and the aerosol scattering. Sun reflection of water surface and water leaving radiance can be computed by the radiation models, which are depended on the satellite orbit parameters (satellite altitude, inclination angle, crossing equator time and satellite fight direction), sensor properties (FOV, scanning rate, band wavelength), air condition (pressure, visual visibility, wind speed etc.) and water condition such as the concentration of the chlorophyll, suspended matter and yellow substance. Secondly, in the paper, it is focused on calculating the SCS of Chinese Ocean Color and Temperature Scanner (COCTS) which is being planned to be installed in the first Chinese ocean color satellite proposed to launch during the period of Chinese Ninth 'Five Plan' Finally, the SCS response on the time and space has been studied in detail, with the calculation of SCS in various cases, such as different seasons which are substituted by the typical date Vernal Equinox, Summer Solstice, Autumn Equinox and Winter Solstice, and different satellite passing local times from 8:00 to 15:00 as well as the different pixels in one scan line. The results of the study show that the SCS is a philosophic concept provided to predict the quality and to evaluate the availability of the imagery from the Chinese COCTS.