I. Introduction
The rapid development of modern telecommunication systems, radio-electronic equipment, the everyday use of wireless data transmission technologies in everyday life and industry, including the construction of wireless networks for IoT requires the search for new, more efficient, compact and high-quality antenna systems. One of the most common technologies for ensuring optimal transmission and reception of radio signals is the use of microstrip patch antennas and antenna arrays based on them. These antennas are widely used in the microwave, millimeter and terahertz ranges [1]-[3]. To achieve optimal performance and efficiency of use of antenna systems, it is important to choose an effective method of powering the elements of the antenna array. One of these methods is the excitation of the antenna array by a planar waveguide with a quasi-TEM wave.