An underwater multi-channel radiometer, which can be moored on the optical buoy for time series observation of downwelling spectral irradiance and upwelling spectral radiance in seawater, is designed. The biofouling on optical window is protected successfully by using an auto-operated mechanical anti-biofouling-blush. High-sensitivity electrophotonic detector and high precision ADC are combined to detect the weak optical signal in deep water. This instrument is powered by self-stored battery and discontinuous power supply mode is used in order to reduce the power consumption. The real time communication between the radiometer and the control center of ocean optical buoy is achieved by using an underwater inductive modem. The instrument has the characteristics of high accuracy, low power consumption and low self-shading error.
downwelling spectral irradiance
upwelling spectral radiance