Echo simulator and simulated echo generating method of universal airborne radio altimeter

The invention provides an echo simulator of a universal airborne radio altimeter. The echo simulator comprises a control unit, a receiving unit, a down-conversion link unit, a digital radio frequency storage unit and an up-conversion link unit, wherein the control unit is used for establishing an echo system function; the receiving unit is used for receiving radio frequency signals transmitted by the radio altimeter; the down-conversion link unit is used for generating clock information and carrying out down conversion on the radio frequency signals to obtain zero-intermediate-frequency transmission signals of the radio altimeter; the digital radio frequency storage unit is used for carrying out convolution on the zero-intermediate-frequency transmission signals of the radio altimeter according to the clock information and the echo system function so as to obtain intermediate-frequency echo signals; and the up-conversion link unit is used for carrying out up conversion on the intermediate-frequency echo signals so as to obtain radio frequency echo signals. The embodiment of the invention can adapt to various airborne radio altimeters, can be used for generating comprehensive and high-accuracy echo signals and can be used for more comprehensively checking and testing functions and indexes of the airborne radio altimeter during the design, debugging, test, delivery and acceptance of the radio altimeter. The invention further provides a simulated echo generating method of the universal airborne radio altimeter.