A 4 × 4 Active Antenna Array with Adjustable Beam Steering

Area of Science:

• Electrical Engineering
• Antenna Theory
• Wireless Communication

Background:

• Accurate beam steering is crucial for reliable point-to-point communication systems.
• Component variations in antenna arrays can lead to phase errors and reduced steering accuracy.
• Existing methods may lack the precision required for critical communication links.

Purpose of the Study:

• To develop an adjustable 4x4 antenna array with enhanced electrical beam steering accuracy.
• To implement a calibration technique that compensates for component variations and improves steering precision.
• To demonstrate polarization control capabilities for versatile signal transmission.

Main Methods:

• A calibration procedure involving measurements of unit cells at various voltage bias points.
• Calculation of an average phase shift profile model to reduce component-induced errors.
• Post-calibration adjustment of beam steering angles in beamforming calculations.
• Far-field measurements at 3 GHz to validate steering accuracy.

Main Results:

• Achieved initial beam steering angles with fair accuracy at 3 GHz.
• Improved steering accuracy to within 2 degrees by fine-tuning beamforming calculations.
• Demonstrated incremental beam steering from 0 to 45 degrees.
• Observed antenna gain ranging from 4.7 dB to 2.8 dB across the steering range.
• Successfully demonstrated polarization control in horizontal and vertical directions.

Conclusions:

• The proposed calibration and adjustment technique significantly enhances beam steering accuracy in 4x4 antenna arrays.
• This method provides robust and precise beam steering, critical for preventing transmission failures in point-to-point communication.
• The adjustable antenna array offers effective polarization control and reliable performance across a range of steering angles.