High-efficiency wideband transmit-array antenna with linear polarization in Q-band

A new linearly-polarized discrete lens antenna for satellite applications is designed in 42-GHZ band with 1-bit phase quantization and attractive unit cell design. A three-layer structure is adopted for the phased array to achieve design simplicity. The unit cell is characterized by using Gaussian optics measurements. The design and optimization of the power budget has been theoretically analyzed and verified experimentally. The unit cell's impedance matching measurements show a reflection loss below −10 dB at 40.3-42.6 GHz and an insertion loss of 0.42 dB at 41.5 GHz. The proposed discrete lens antenna achieves directivity/gain values of 25.1/22 dBi. Power efficiency of 50% is also achieved with a 3-dB gain bandwidth of up to 8.7%, and very low cross-polarization levels.