UHF phased-array measurements in snow

The installation and operation of large, horizontal, UHF phased-array antennas in arctic regions is challenged by severe environmental conditions. It can be shown that large and moderate snowfall can impact the operation of exposed dipole array elements, and can reduce aperture efficiency. Reflection coefficients, measured at the antenna terminal of an embedded array element, can vary drastically as a function of snow depth and density. In this paper, we describe several measurements that show embedded-array-element impedance variations as a function of snow height. Measured results are presented for an array operating from 400 MHz to 470 MHz.