Joint Azimuth-Velocity Estimation for Moving Targets With 2-D Frequency-Mode Hopping OAM Radar

Traditional pulsed orbital angular momentum (OAM) radars sequentially switch OAM modes between pulses to estimate target azimuth by leveraging intermodal phase differences. However, this approach is inherently limited because target radial velocity introduces Doppler-related phase variations across pulses, which corrupt the intermodal phase differences and degrade azimuth estimation accuracy. To address this challenge, we propose an OAM-based 2-D frequency-mode hopping radar (FMHR) that integrates OAM-frequency hopping via established 2-D frequency-mode coding. This scheme enhances target information acquisition by expanding the joint parameter space dimensionality and improving signal orthogonality. Simultaneously, interpulse parameter agility is employed to resolve range ambiguities. Furthermore, we develop a dedicated sparse reconstruction model for FMHR to achieve phase decoupling and enable high-range resolution through synthetic bandwidth. Comprehensive numerical simulations validate the system’s effectiveness and demonstrate its superior performance in suppressing deceptive jamming compared to conventional methods.