GPS Anti-Jamming Antenna Radiation Pattern Based on Power Inversion Algorithm

The power inversion algorithm is a classic adaptive beamforming technique in GPS anti-jamming systems. This algorithm adjusts the weight vector of the antenna array to create nulls in the direction of interfering signals while maintaining normal reception of GPS signals. In MATLAB implementation, this typically involves calculating covariance matrices and solving optimization problems to determine optimal weights.

Visualization of radiation patterns is crucial for understanding algorithm performance. In MATLAB simulations, 2D or 3D radiation patterns are commonly displayed to intuitively show the gain response of the antenna array in different directions. The power inversion algorithm's pattern characteristics show distinct nulls in interference source directions while maintaining high gain in satellite signal directions. Code implementation often uses polar or 3D plotting functions to visualize these patterns effectively.

The core concept of this algorithm is interference suppression through minimizing array output power. Since GPS signal power is much lower than interference signals, the algorithm prioritizes suppression of strong interference sources. It's important to note that when interference directions approach satellite signal directions, some GPS signal attenuation may occur. The algorithm implementation typically involves eigenvalue decomposition or adaptive filtering techniques to achieve this power minimization.

Beamforming performance is influenced by multiple factors including the number of array elements, element spacing, and signal incidence angles. In simulations, these parameters can be adjusted to observe changes in radiation patterns, which helps understand the relationship between array geometry and anti-jamming performance. MATLAB code for such simulations often includes parameterization of array configurations and real-time pattern updates when parameters change.