Explain beamforming algorithms for array signal processing.

Beamforming combines signals from sensor arrays to enhance desired direction and suppress others. Delay-and-sum: Align signals by steering delays, sum constructively for target direction. MVDR/Capon: Minimize output power while maintaining unity gain for desired direction, adapts to interference. LCMV: Multiple linear constraints for nulling specific directions. MUSIC/ESPRIT: Subspace methods for high-resolution DOA estimation. Implementation: Spatial covariance estimation, weight calculation, and real-time processing. Challenges: Calibration errors, near-field effects, wideband signals, and computational complexity. Applications: Radar, sonar, communications, microphone arrays, and medical imaging.