Radiation from a slotted rectangular waveguide filled with asymmetrically biased ferrites is investigated in this study. A theoretical model of slotted parallel plates is used for analysis. A boundary value problem is rigorously solved with the Fourier transform and mode matching method to obtain simultaneous equations. The radiation field is represented in a fast convergent series that is efficient for numerical calculation. The radiation behaviors are estimated in terms of ferrite configurations and bias fields. Maximum angular scanning of 90.2 degrees is achieved when the DC magnetic bias field varies from 0 to 2,000 oe.