Achievement of pencil-beam radiation from a TM01 mode circular waveguide source using multi sector dielectric lens

A method of improving radiation from TM01 model conical horn is presented, drielectric lens consisted of a number of sectors locates on aperture plane of conical horn, appropriate thickness of each sector is choosed ,the conical horn can radiate circular polarized pattern,with a boresigh peak . Radition fields of the horn are gived by analytic formulae and analytic results agree well with that of numerical simulations ,the geak pattern gain of the horn with multi-Sector dielectric lens is about 19.6dB,bandwidth is approximately 15.8%(S11<0.2),aperture efficiecy is 31.8% at 5GHz．