Abstract: The way to simulate the altitude signal for radio altimeter is discussed in the paper. Because the DRFM can copy the fine characteristic of signal, it can be used to simulate the altitude signal which the altitude volume can be adjusted continuously and the jamming signal can be added to it. As important, many key technologies are discussed in the paper, such as dater cyclic storage technologies, digital noise modulation technologies and false target interference signal technologies etc.

Key words: DRFM, ⁺Radio altimeter, +Cyclic storage, ⁺False target interference signal