Various feasible solutions of Irbene RT-32 secondary focus feed antennas are designed and compared in the present study. The examined feed antennas include smooth wall and corrugated horns with linear and shaped profiles. Mode matching technique is employed for simulation of scattering parameters and radiation patterns. Genetic algorithm is used for optimisation of horn profile for the best cross-polarization, and aperture efficiency performance. Although the presented horns are valid for any frequency band, different solutions allow choosing the best combination of factors, such as electrical parameters, bandwidth, physical size and complexity of manufacturing.