A flat four-beam switched array antenna

A low-profile four-beam switched array antenna for mobile terminals is proposed in this paper. A flat antenna concept modeled as a square magnetic line current array is realized by thin trapezoidal cavity elements. A unidirectional beam is obtained which can be redirected by alternating input terminals of the hybrid coupler. Element characteristics are calculated approximately using a cavity model with the two-dimensional finite-element method. Input characteristics and radiation pattern of the array antenna are evaluated by experiments.