A broadband wide angle variable linear polarization rotator

A Ku-band wide angle variable linear polarization rotator with high cross-polarization discrimination (XPD) was designed, fabricated and measured. The rotator makes use of two 90° meanderline polarizers and a linear grid to perform the polarization rotation and cross-polarization suppression. The advantage of the present arrangement is that it requires only one rotating mechanism rather than the multiple mechanisms commonly required when only linear grids are used. Across the 90° angular range of rotation and for incidence angle up to 45°, the XPD is found to be better than 28 dB over a 20% frequency bandwidth.