Patent attributes
A dual band antenna array comprises a pair of coplanar antenna elements, the first antenna element excitable at a frequency within a first frequency band, the second antenna element excitable at a frequency within a second frequency band. A single transmission feed line in a second plane has an input for receiving a signal, the feed line dividing at a branch point into a first line segment for communicatively coupling the first antenna element with the input at a first feed point, and a second line segment for communicatively coupling the second antenna element with the input at a second feed point. The first and second line segments have lengths adapted for impedance matching at the first and second frequency bands, respectively, relative to the feed line input, to selectively allow energy transmission in one of the first and second line segments while reflecting energy in the other line segment according to the input signal frequency, whereby the activated antenna elements are passively switched based on the input signal frequency.
