Microstrip Antenna Feeding Techniques There are four popular antenna feeding techniques which are microstrip line, coaxial probe, aperture coupling and l proximity coupling. They are further divided into two main groups: contact (microstrip line and coaxial probe) and non-contact (aperture coupling and proximity coupling). For the contact method, RF power is directly supplied to the radiating zone while without contact method, electromagnetic field coupling is performed to transfer power between the microstrip line and the radiating zone [ ]2.6.1 Power supply of the microstrip line L The microstrip line feed is one of the simplest methods to fabricate as it is a simply conductive strip that connects to the patch and therefore can be considered an extension of the patch. It is simple to shape and easy to match by controlling the position of the insert. However, the disadvantage of this method is that as the thickness of the substrate increases, surface waves and spurious power radiation increase which limits the bandwidth. 2 Figure 2.6: Microstrip line