A polarizer system consisting of two quarter-wave polarizers in tandem for polarization alignment of linearly polarized signals is reported. The required on-axis isolation is 35 dB for the total antenna system, which cannot be achieved using existing polarizers. The system applies a new, extremely wideband polarizer to meet the isolation requirement. Measured isolation for the entire system is higher than 38 dB over the 10.95-14.50 GHz frequency band. The transmission loss is below 0.15 dB in the same band, and the return loss below -25 dB when the band 12.75-14.00 GHz is excluded. The new polarizer makes it possible to align the antenna to receive the correct polarization over a wide frequency band by only rotating one of the polarizers.