AIRBORNE IMAGING RADIOMETER SCAN SIMULATION

An imaging radiometer scan simulation program is developed for comparing the performance of different scan patterns and process behavior under varying circumstances, The program gives the radiometer's antenna beam the desired scan motion over an artificial target scene, computes the antenna radiometric temperature as the convolution of the antenna pattern with the scene brightness temperature deviation, computes a moving average of the antenna output, and records the data values as well as the corresponding coordinates at the sampling moments. The simulation indicated that a helicopter-borne imager needs at least passive attitude stabilization. In addition, the state-of-the-art sampling rate was found to be too slow, if the sampling period is set equal to the integration time, A detailed study revealed the achievable spatial resolution (line pairs/length unit-definition) to be 1.0-1.2 x footprint dimensions, but the integration and sampling periods should be as short as 0.2-0.4 x footprint dimensions.