Microstrip Antenna Feeding Techniques There are four popular antenna feeding techniques which are microstrip line, coaxial probe, aperture coupling and proximity coupling. They are further divided into two main groups which are contact (microstrip line and coaxial probe) and non-contact (aperture coupling and proximity coupling). For contact method, RF power is supplied directly to the radiating patch while no contact method performs electromagnetic field coupling to transfer power between the microstrip line and the radiating patch [ ]2.6.1 Line power microstrip The microstrip line feed is one of the easier methods to manufacture as it is a simply conductive strip connecting to the patch and therefore can be considered as an extension of the patch. It is simple to model and easy to match by controlling the position of the inset. However, the disadvantage of this method is that as the thickness of the substrate increases, surface waves and stray radiation increase, which limits the bandwidth. 2 Figure 2.6: Microstrip line