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 inter-modal phase differences. However, this approach is inherently limited because target radial velocity introduces Doppler-related phase variations across pulses, which corrupt the inter-modal 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, inter-pulse 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.