Abstract
The purpose of this project is to design, simulate, fabricate and test a broadband microstrip balun circuit at a center frequency of 5 GHz. For this to be accomplished a proper design is selected by the combination of various passive microwave circuit elements to obtain the best results ,which means an acceptable magnitude and phase balance between the output signals under consideration in the balun circuit . Throughout the length of this document, the basis of balun circuit, implementing the optimized balun circuit and the practical and theoretical results will be discussed.