Hybrid digital-analog beamforming architecture for rapid beam steering based on microwave photonics

This Letter proposes a hybrid digital-analog microwave-photonics beamforming architecture, which is highly suitable for space-ground integrated network communications due to its high scanning speed and precise pointing capabilities. The frontend digital module generates phase-coded microwave waveform at different slopes, while the backend analog module aligns the beamforming using fixed optical true-time delays to achieve beam pointing in various directions. Beam switching is controlled solely by digital encoding, enabling an arbitrary angle switching time of less than 5 ns. Experiments demonstrate that the beam pointing error is less than 0.70° for four phase slopes.