High-Gain Millimeter-Wave Beam Scanning Transmitarray Antenna

In this article, a high-gain millimeter-wave transmitarray antenna (TAA) maintaining scanning ability is developed, integrating an array feed as the primary emitter. The work is achieved within a limited aperture area, avoiding the replacement or extension of the array. The addition of a set of defocused phases along the scanning direction to the phase distribution of the monofocal lens allows the converging energy to be dispersed into the scanning scope. The beam forming algorithm proposed in this article can determine the excitation coefficients of the array feed source, and is beneficial to improve the scanning capability in array-fed transmitarray antennas. A transmitarray based on the square waveguide element illuminated by an array feed is designed with a focal-todiameter ratio (F/D) of 0.6. A 1-D scan with a scope of 5(circle) to 5(circle)is realized through calculation. The measured results show that the transmitarray can achieve a high gain, 37.95 dBi at 160 GHz, although a maximum 2.2 dB error appears compared with the calculation in the operating band of 150-170 GHz. The proposed transmitarray has been proven to generate scannable high-gain beams in the millimeter-wave band and is expected to demonstrate its potential in other applications.

Automated summary

In this article, a high-gain millimeter-wave transmitarray antenna (TAA) with scanning ability is developed using an array feed as the primary emitter. The addition of defocused phases to the phase distribution of the lens enables energy dispersion into the scanning scope. The proposed beam forming algorithm improves the scanning capability of the transmitarray. A transmitarray based on square waveguide elements achieves a high gain of 37.95 dBi at 160 GHz, despite a 2.2 dB error compared to the calculation in the operating band of 150-170 GHz. The transmitarray demonstrates its potential for generating scannable high-gain beams in the millimeter-wave band.