Technical research and experimental validation of radar-integrated navigation for high-G munitions

As research on smart munitions advances, a significant challenge arises: electronic components possess poor tolerance to overload. Consequently, during the high-overload launch environment inside the barrel, these components are powered down, necessitating initial attitude alignment after launch. Utilizing the Earth’s magnetic field for initial attitude determination exhibits clear limitations, while satellite navigation suffers from long cold-start times, rendering it unsuitable for short-duration operational scenarios. This makes it difficult for the navigation system to obtain both an accurate initial attitude and rapid position fixing. Moreover, the high spin rates generated under extreme overload place stringent performance requirements on inertial navigation gyroscopes, substantially increasing system cost—an especially pressing issue for single-use munitions. To overcome these constraints, we designed a novel integrated navigation system. This system first leverages the strategic placement of antennas on the munition. By analyzing the relative signal strength trends between these antennas, an initial roll angle estimate (with bounded error) is obtained. Subsequently, a Kalman filter fuses data from low-cost Micro-Electro-Mechanical Systems (MEMS) gyroscopes and ground-based phased-array radar for integrated navigation. This fusion continuously compensates the attitude angles in real-time, resolving the critical issues of initial attitude assignment and gyroscope drift accumulation during the operational phase. Digital simulations and experimental data demonstrate that this system provides excellent initial roll angle estimation and effective convergence of the integrated navigation solution. It effectively solves the problem of obtaining an initial attitude reference under the challenging constraints described.