The purpose of this thesis is to perform an analysis on antennas implemented using the Substrate Integrated Waveguide (SIW). A complete knowledge of the behaviour of various aperture shapes on the Antenna's performance is researched and analysed by designing and simulating different structures. As part of the Study primarily three conceptually different structures are analysed. The dual sided Z shaped Slots Leaky Wave Antenna at 2.5GHz, Single and Multi Element based Single Layer Broadband Antenna and Multi Element based Multi-Layer Broadband Antenna. The Broadband Antenna are designed for a higher frequency range of 12-20GHz. The feed for all the antenna structures has been chosen as the Microstrip Line feed and it is tapered to keep return loss to minimum value and phase cancellations. The various antenna structures have been designed and simulated for comparing the variations in the return loss, realized gain and VSWR. The pros and cons of each structure is scrutinized and presented in the study. The antenna parameters are compared and study aims at showcasing the antenna with the best performance features. Master of Science (Communications Engineering)