DISCRIMINATING DEVICE TO GROUND

摘要

PURPOSE:To obtain a discrimination information to ground required in the stage of flying at an ultra low altitude flight by analyzing the output signal of an FM- CW system radio altimeter. CONSTITUTION:Out of the output signals of an FM-CW system radio altimeter, an IF signal is inputted to a terminal 1 and an altitude signal to a terminal 2, respectively. The IF signal of the terminal 1 is applied to a frequency analyzing circuit 3, by which the frequency spectrum of the IF signal is obtained. The IF signal branched to another detecting circuit is subjected to detection processing and is outputted to an A/D conversion circuit 5. This is accomplished in order to analyze the IF signal at power levels. In a correction circuit 7, the deviation of the IF signal produced by a change in altitude is corrected by using the altitude signal inputted from the terminal 2. This corrected signal discriminates the state from the ground by the reference data stored in the data memory 8C of a storage circuit 8.