Collinear Microstrip Patch Antenna

The paper presents a brief overview of the development of so called collinear types of antenna arrays. A new type of this structure in microstrip technology is further introduced. The principle of the antenna operation is explained via surface current distribution of excited modes. Such distribution is reached via geometrical perturbation of a radiating element by slots introduced in such a way that they eliminate radiation from even half current wavelengths. The initial design and optimization of the prototype operating in RFID band (869 MHz) has been performed in planar simulator Zeland IE3D. A prototype has been realized and measured. The reached results show that the presented antenna has directional character as it can be expected due to the proposed technology and the presence of a planar ground plane.