A Low-Profile 2D Passive Phased-Array Antenna-in-Package for Emerging Millimeter-Wave Applications

article covers the implementation, calibration, and measurement aspects of a low-profile 4 x 4 passive phased-array antenna-in-package (AiP) employing the beamformer discussed in [9]. The antenna array comprises slot-coupled patch antennas with left-handed circularly polarized (LHCP) radiation. Microelectromechanical system (MEMS)-like tunable phase shifter (PS) functioning based on controlling the phase constant of a slow wave microstrip line is employed for the phase tuning. Measurement results show the antenna"s main beam can be steered over an angular range of +/- 30(?) in both elevation and azimuth planes. The operating frequency bandwidth of the system ranges from 28 to 30 GHz. The peak directivity and the radiation efficiency of the antenna system are 18.48 dBic and 58% at Boresight at 29 GHz, respectively. The efficiency drops 16% when the steering angle reaches the maximum.