High-gain transmit-array antenna using only triple-layer metal elements for backhaul Communications

A Ka-band dual linear polarized high-gain transmitarray antenna (TA) is proposed for millimeter wave wireless backhaul communication. The TA includes, 36×36 metal-dielectric unit cells (UCs). Each UC consists of three metal layers with two-layer dielectric substrates and does not contain any via connection between layers for easy processing and integration. The flat TA lens antenna is predicated on UCs with 12 different phase states covering the frequency band 26-30 GHz, which forms a 3-bit phase quantization of the whole 360° transmission phase. The TA owns 3 dB gain bandwidth of 3.4 deg, peak gain of 27.5 dBi, and aperture efficiency more than 35%. The cross polarization of the TA is more than 30 dB in the full frequency range. The performance of the TA satisfies the application of the backhaul communication system.