Real-Time Accurate Altimetry Based on Satellite Reflection Signals

Altimetry based on Global Navigation Satellite System - Reflection (GNSS-R) is widely used in the field of surveying and mapping. Existing GNSS-R technology focuses on measurement accuracy and neglects real-time measurement. Precision strike bombs need to be detonated at different elevations according to the established mission, which requires a missile-borne detector to realize high-precision and real-time missile elevation measurement. Based on this, a spatial alternating maximum likelihood algorithm based on satellite reflection signals is proposed. The algorithm combines the code phase altimetry, multi-frequency joint processing technology and multi-antenna technology, and finally obtains the real-time missile height by searching and estimating the signal pitch angle, time delay and Doppler frequency deviation parameter in three dimensions of air, time and frequency domains. The simulation results show that the method has good real-time and accuracy in the height measurement of a high-speed flying missile-borne detector.