Tri-layer linearly-polarized discrete lens antenna operating in X-band, design & characterization

This research work presents the design and characterization of planar discrete lens antennas (TA Transmit-Array antennas) based on a simple tri-layer elementary cell operating in the 10-GHz band. The structure of the proposed elementary cell allows 1-bit and 2-bit phase quantization and easy fabrication with a simple printed-circuit board. The linear/circular polarization can be generated with 1-bit/2-bit configuration. The elementary cell consists of two C-slot loaded patch antennas interconnected by a metalized via hole. The simulation of the elementary cell has been validated by the measurement that confirmed a good accord in terms of return loss (10 dB-bandwidth is equal to 9%) and insertion loss (0.35 dB at 10 GHz). The linearly-polarized transmit-array achieves a maximum directivity of 25.1 dBi and a gain of 22.7 dBi. The 1-dB gain bandwidth is up to 9.6% around 9.8 GHz with 56.3% of radiation efficiency. Beam-steering up to 30° is achieved by tilting the focal source.