Antenna Array Phase Calibration via Feedback Signals

The patent uses feedback signals (CQI, SINR measurements) from wireless communication devices to iteratively optimize beamforming phase values. The base station transmits reference signals, receives quality measurements from devices, and adjusts phase values to maximize signal quality while minimizing interference. This closed-loop feedback mechanism enables dynamic adaptation of beamforming parameters to achieve both high beam gain and adequate beam isolation.

The patent transitions from static beamforming (fixed phase values) to dynamic beamforming where phase values are continuously optimized based on real-time feedback. The system iteratively adjusts phase values across multiple iterations, adapting to changing channel conditions and device positions. This dynamic optimization enables the system to maintain optimal beam gain while adapting beam direction and shape to reduce interference with other users.

The patent optimizes phase values as key parameters to achieve optimal balance between EIRP and beam isolation. By iteratively adjusting phase values based on feedback measurements, the system finds optimal phase configurations that maximize main beam gain while suppressing sidelobes and reducing interference. The patent also explores amplitude adjustments in some embodiments to further optimize the trade-off between total radiated power and spatial isolation.

The patent applies different phase values to different antenna branches to create directed beams with specific spatial characteristics. Instead of uniform phase distribution, the system tailors the phase profile locally at each antenna element to achieve focused main beams and suppressed sidelobes in specific directions. This local optimization of phase quality enables high EIRP in desired directions while minimizing interference in other directions.

The patent uses feedback measurements of actual received signal quality (CQI, SINR) to evaluate the true impact of beamforming configurations on system performance. Rather than relying on theoretical sidelobe calculations, the system measures actual interference and signal quality at the receiving device. This enables optimization of phase values to achieve adequate beam isolation without excessive tapering that would cause EIRP loss, as the feedback reveals the actual performance impact.

The patent applies iterative optimization that gradually refines phase values to achieve sufficient but not excessive beam isolation. The system performs multiple iterations with progressively improved phase configurations, stopping when performance gains diminish. This partial action approach achieves adequate sidelobe suppression for practical interference reduction without the excessive tapering that would cause significant EIRP loss, optimizing the trade-off based on actual system requirements.