This paper gives two kinds of circular polarizer made of several pho to-etched copper strip or strip-grid fiberglass epoxy plates. One is called strip type

the other strip-grid type. The former has good performances at center frequency

the latter has broad-band performance. These two polarizers may be made into a polarized board as a cover set in front of the waveguide horn. Using curves and formulas given in the paper

the design and calculation may be very simple. Experiments have shown that within about 20% of the band-width of the strip type polarizer the axial ratio of circular polarized field is better than 2 dB and VSWR less than 1.1

and that within more than 20% of the band-width of the strip-grid type polarizer the axial ratio of circular polarized field is better than 1dB and VSWR less than 1.1.