Directed energy systems (DES) are a class of systems used for various purposes like Electronic warfare, remote mine clearing and testing the vulnerability of electronic systems under Electromagnetic radiation. They have several advantages over conventional weapon systems like limited debris or garbage production and also they are affected less by rain or fog. For DES, a high power source like virtual cathode oscillator (vircator) or relativistic magnetron is used. These sources have the capability to produce power in the range of Gigawatts. The high power electromagnetic (EM) waves produced by these systems need to be directed at a distance through special devices called mode converters.This is because most of the EM waves produced by these devices consist of the TM01 mode, which has a null in its radiation
pattern and so cannot provide a high radiation gain. On the other hand the TE11 mode has a highly directive radiation pattern. The problem with most available
mode converters is that either they do not have a linear profile or they achieve mode conversion through a series of intermediate steps. In this work we propose a new design which is linear yet achieves mode conversion without intermediate steps. A tapered baffle based design is used for this purpose. The proposed design has the added advantage of being able to transmit the TE11 horizontal mode through it without distortion.