Phased Array Antennas

Phased array antennas are one of the easiest ways to achieve beamforming and beam-steering. A phased array antenna can be understood using the analogy of an N -slit diffraction experiment where the overall beam from the array is a result of coherent constructive interference ofN sources (or independent antenna elements in an array). Each antenna element in the array is fed with a phase shift, introducing a time delay in the radiated beam. The constructive interference of these time-delayed beams from each radiating element enables directional control. A simple representation of the beam tilt because of the phase shift in different elements using an array of six open-ended waveguides is shown in Figure 3. The radiation pattern and tilt angle for such antennas can be estimated using the array factor. Detailed mathematics for the calculation of tilt angle is provided within the Supplementary Information.