A W-band directional radiation antenna loading dielectric sheet based on SIW technology

In order to improve the gain of the array antenna element in the W-band and reduce its horizontal dimension, The directional radiation antenna loading dielectric sheet based on SIW technology is proposed. The antenna uses a conventional micro strip line to feed the gradient open micro strip line. Then the gradient open micros trip line feeds the SIW. Finally, the dielectric sheet loaded in SIW will radiate the W-band electromagnetic wave. After modeling and simulating in CST Microwave Studio ® , the antenna model has a reflection coefficient which is less than −10 dB over range of entire 86.04–110 GHz frequency. And the gain at the typical frequency of 94 GHz reaches 16.1 dB, the side lobe level is below −13.7 dB. The horizontal dimension of the antenna is calculated to be 0.658 time of wavelength according to the electrical size corresponding to 94 GHz. The designed antenna has the characteristics of small horizontal dimension, high gain and lower side lobe, and can be applied to the antenna array of passive millimeter wave imaging system.