Aiming at problem of accurate height measurement when airdrop parafoil flare

acoustic altimeter is proposed to improve accuracy of height measurement signal based on analysis on advantages and disadvantages of existing height measurement devices.Research and fabrication of principle prototype of acoustic altimeter system is completed firstly

and then experimental study in the case of different height are carried out by using the designed acoustic altimeter system in indoor and outdoor

aiming at different reflective surfaces

the mean of maximum measurement errors of post-processing of multigroup test datas respectively are 0.326 m indoor and 0.814m outdoor

these results show that measurement precision of the altimeter system can meet airdrop requirement at range of measurement.