Characteristic of a digital correlation radiometer back end with finite wordlength

The performance characteristic of a digital correlation radiometer signal processing back end (DBE) is analyzed using a computer simulator. The particular design studied here corresponds to the airborne Hurricane Imaging radiometer which was jointly developed by the NASA Marshall Space Flight Center, University of Michigan, University of Central Florida and NOAA. Laboratory and flight test data is found to be in accord with the simulation results. Overall design seems to be optimum for the typical input signal dynamic range at the DBE input. It is found that the performance of the digital kurtosis could be improved by lowering the DBE input power level. An unusual scaling between digital correlation channels, observed in the instrument data, is confirmed to be a DBE characteristic.