Mode Conversion From TE11 to TM11 in Circular Waveguide Using Step Discontinuity Method for Ku-Band Applications

This paper discusses about the Mode Conversion from TE11 to TM11 mode in circular waveguide using step discontinuity is investigated. We use this method for Ku band (12GHz – 18GHz) application and our designed frequency is 15 GHz. We get the amount of power converted from TE11 to TM11 is 10 to 20 %. In this paper we have designed the light weight, compact size and high directivity Circularly Polarized waveguide with high Directivity, high Gain, low return losses and good VSWR. It is found that an abrupt change in guide radius (step) will produce a wide range of mode conversion which can be used in most dual – mode feed horn applications. The step discontinuity is found to produce relatively constant mode conversion over a wide band of frequencies. In this we have varied the length, flare angle, aperture diameter of the conical antenna These dimensions will explain the required features such as impedance matching, radiation pattern of the conical antenna. The electromagnetic accuracy of the antenna is measured with the help of High Frequency structure simulator (HFSS) Software. The measured results of the conical antenna confirmed the simulation results and satisfied the design requirement. In view of this paper, the measured results show that this antenna has gain of 10.80 to 13.20 dB, bandwidth of 300 %, return losses level of -25dB. Simulation for horn antenna has been done on Ansoft HFSSv11.