Mechanically Reconfigurable Linear Array Antenna Fed by a Tunable Corporate Waveguide Network With Tuning Screws

A mechanical technique to provide beam-steering capabilities to a linear array antenna is presented. The methodology is based on the insertion of metallic tuning screws into power dividers in rectangular waveguide technology. These tuning screws establish a short circuit between the top and bottom plates of the waveguide, and a phase change in the transmitted signal is then generated. Therefore, the phase difference between the output ports of a conventional waveguide divider can be controlled with these tuning screws. A corporate waveguide feeding network with several tuning screws has been designed. This tunable waveguide network is used to feed an aperture stacked patch array, forming the final mechanically reconfigurable linear array. Seven different phase configurations have been synthetized by using the tuning screws, which provide a noncontinuous angular scanning. In particular, a main beam steering from -26° to +26° with 13 discrete radiation patterns has been obtained. The use of waveguide technology makes the proposed reconfigurable antenna suitable for low-loss and high-power applications. Total efficiency values higher than 90% have been achieved for every configuration.