In work are synthesised optimal and quasioptimal algorithms of signal processing of radio thermal radiation in modulation type radiometric systems in the assumption that the transfer characteristic of an entrance path fluctuates in time. These algorithms allow raising accuracy characteristics and, accordingly, reliability of radiometric measurements and parameters estimations of investigated environments. Conditions at which quasioptimal algorithms are close to zero-type, modulation (with relation calculation of intensity signals), classical modulation (Dike radiometer) and noise-compensated radiometers are established. Limiting accuracy of measurements is calculated. The new approach to estimation of fluctuating sensitivity is offered and potential fluctuating sensitivity is calculated.
modulation type radiometer, optimal algorithm, potential accuracy of estimation