The paper presents the concept of a fully planar treeshaped antenna with quasi-fractal geometry. The shape of the proposed radiator is based on a multi-resonant structure. Developed planar tree has symmetrical branches with different length and is fed by a coplanar waveguide (CPW) with modified edge of the ground plane. The antenna of size 29 mm x25 mm has been designed on Taconic -RF-35 substrate (r = 3.5, tg= 0.0018, h = 0.762 mm). The paper shows simulated and measured characteristics of return loss, as well as measured radiation patterns. The proposed antenna could be a good candidate for broadband applications (for instance: wideband imaging for medical application and weather monitoring radars in satellite communication etc.) Keywords-broadband antenna, fractal antenna, reflection coefficient, defected ground structure, coplanar waveguide I. INTRODUCTION NTENNA (radiator) could be called a main component in wireless systems, because based on its performance is easily to estimate and analyze effectiveness of the wireless communication around the world. Radiator is a transducer which task is carrying the current. The antenna, in accordance with the general definition, is used to convert radio frequency (RF) fields into alternating current or vice versa. There are both receiving and transmission antennas for sending or receiving radio transmissions [2]. Therefore, the antennas are very important in wireless systems, because they transmit and receive the information via the air [2,11].Since the beginning of the 21st century, the design and analysis of antennas and antenna arrays for broadband and Ultra WideBand systems (UWB) are characterized by growing interest. Various applications of electronic systems require designers to pay attention on different properties of antennas, depending on the criterion chosen, for example: size, bandwidth, radiation pattern, gain, efficiency and impedance matching. In world literature, the prevailing proposals include single radiators in a wide range of shapes: from the classic ones (rectangle, triangle, circle) to fractal (curves filling space) and nature shapes (flower, tree); there are also examples of large antenna arrays, but there are definitely fewer ideas [8,9,10].The microstrip antenna can be a good idea for wideband or UWB system, because it is characterized by the small profile, easy to fabricate and very low cost of fabrication. The microstrip technology consists of two main parts on a dielectric substrate. They are: microstrip transmission line and ground plane which are made of conducting material on one side or on the both sides [7].The article briefly reviews a couple of different antennas for the broadband applications, constructed over the last decade (2008 -2018). It is summarized in the form of project of a M. Malinowska and M. Kitliński are with
