An anti-jamming and azimuth angle estimation algorithm for omni-directional VHF radar

For omni-directional VHF radar, an improved antijamming and angle estimation algorithm is proposed to decrease the cancellation loss of target's echo due to the small azimuth angle difference between the jamming and target and increase the estimation precision of target's azimuth angle. In the proposed method, two circular arrays with different sizes are adopted. The small one is firstly used to estimate the azimuth angle of the jamming after suppressing the jamming in phase mode -1 and 1 with phase mode 0. Then in the big one, the jamming in phase mode -3 and 3 is respectively cancelled by phase mode 2 and -2. After that, by combing the estimated azimuth angle of jamming, the newfound phase mode 3 and phase mode -3, we can get more precise azimuth angle of the detected target compared with that obtained in single circular array. Simulation results demonstrate the effectiveness of the proposed algorithm.