A shaped reflector antenna for 60-GHz indoor wireless LAN access points

This paper addresses the design of a 60-GHz shaped reflector antenna that h as to illuminate a predefined circular area without substantial spatial var iation. At the boundary of this coverage area, the field strength has to fa ll off rapidly. Such efficient and confined illumination may be required in wireless networks that have to cope with a stringent link budget and/or re quire low channel dispersion. Typical examples are the emerging broadband w ireless networks for customer premises and residential applications that wi ll operate in the millimeter-wave frequency region. The particular property of the considered reflector is its diverging surface instead of the common ly applied converging shape. It is shown that the spatial variation within the defined coverage area can be within 1 dB, provided that the antenna is perfectly constructed. It is also shown that practical imperfections such a s axial and lateral feed displacement and mispointing of the feed on top of effects due to blocking by the feed can contribute to spatial field variat ions on the order of a few decibels.