Height Estimation for Ballistic Platforms using Differential Measurements

Use of radio waves is a very common choice for proximity fuzes. The stand-off distance for fuzes varies between a lower and an upper limit depending on the electromagnetic reflectivity of terrain (target). If the reflectivity of the terrain is comparably higher, the return power at the receiver reaches to the threshold level more quickly and the stand-off distance increases. The work presented here introduces an approach to estimate the height of airborne ballistic platforms more precisely compared with the conventional fuzes regardless of the reflection properties of the terrain. Independent measurements of the rate of change of voltage from the receiver and the rate of change of height (from Doppler shift) allow the height to be estimated when the terrain reflectivity is unknown.