MEANDERLINE POLARIZERS

Meanderline circular polarizers are laminated microwave structures printed on a dielectric material. Seavey Engineering designs and fabricates these useful devices to order. When placed over the apertures of horns or flat plate arrays, they convert linear polarization to circular polarization, and vice versa.

Our unique design construction techniques are employed for lightweight structures. Polarizers which can handle up to 100 watts CW per square inch in aerospace environments are also available.

These are low-loss devices with a maximum insertion loss of 0.5 dB. Axial ratio can be held to less than 0.5 dB over 4% bandwidth and less than 3 dB over multi-octave bandwidths.

Meanderline polarizers work well when placed over apertures at least two wavelengths across. Performance deteriorates significantly when the aperture size is less than one wavelength. 

Model 9359-800 - C-Band Meanderline Polarizer. 14.1 inch diameter, 2.45 inches thick. Weight 13 ounces. Sealed for use as a feedhorn cover on a 2.4 meter VSAT antenna. Seven circuit layers. This polarizer has less than 2.3 dB axial ratio and less than 0.5 dB insertion loss over the 3.65 - 6.525 GHz frequency band. Mounting clips are provided to attach to the existing feedhorn.

Model 9359-810 - C-Band Meanderline Polarizer. 18.1 inch diameter, 2.55 inches thick. Weight 20 ounces. Sealed for use as a Cassegrain feedhorn cover. Seven circuit layers. This polarizer has less than 2.3 dB axial ratio and less than 0.5 dB insertion loss over the 3.65 - 6.525 GHz frequency band.

Model 9359-820 - C-Band Meanderline Polarizer. Similar to Model 9539-810 except optimized for better than 1.6 dB axial ratio over 40 MHz bandwidths (4.157 - 4.198 and 6.382 - 6.425 GHz, for example). It is approved for use with INTELSAT 4.5 - 7.0 meter Standard G Earth Stations (Refer to IESS-601, Para. 3.1.2.3 a (ii).)

Model 8741-500 - I/J Band Meanderline Polarizer. Six layers using Duroid circuit material and over-expanded Nomex honeycomb spacers. High power design. Thickness 0.90 inches. Better than 3 dB axial ratio over the 7.0 - 19.0 GHz frequency range.

Model No. 9359-800 C-band Meanderline Polarizer

FREQUENCY-SELECTIVE SURFACES Frequency-selective surfaces function as spatial filters. They consist of laminates of printed-circuit elements which have frequency-sensitive plane wave scattering properties. In Seavey Engineering’s designs, hollow crossed-dipole and Jerusalem Cross elements are used. These are designed using moment methods on a computer. All designs are fully polarization-agile. FSS devices have low-loss transmission and reflection properties. Most designs function as subreflectors in dual-reflector antenna systems. The Model 9170-850 FSS design reflects signals from 9 - 10 GHz and transmits signals in the 2 - 4 GHz frequency band. It is formed onto a small (8.5-inch diameter) hyperboloid subreflector.

Model No. 9170-850 Frequency-Selective Subreflector