On the Benefits of Polarization for Fixed Area Television White Space Devices

The frequency spectrum offered by television white spaces provides an attractive solution to supplying extra bandwidth within large wireless local area networks or wireless backhaul links. However, it is still necessary to ensure for deployment purposes that the primary users, broadcasting services in this case, do not interfere with the white space devices but more importantly that the white space devices do not interfere with the television receivers or television re-transmitters. Given the increased use of vertical polarization as opposed to horizontal polarization in digital television transmission, this paper investigates the benefits of using horizontal as opposed to vertical polarization for white space devices operating within a restricted area. For white space devices such as access points or backhaul links placed at a high height, use of horizontal polarization will reduce their vulnerability to interfere with the primary user regardless of what polarization it has, while also they will be less susceptible to interference from the primary user in locations where vertically polarized television transmitters are deployed.