Patent ID: 7420513
Filing Date: 2008-09-02
Classification: H01Q

Abstract:
1. A circularly polarized antenna device comprising: a conductive ground plane; first and second monopole conductive elements having approximately the same length and respectively connected via connection points to the conductive ground plane; and a feeding point provided at either one of the connection points; wherein the first and second monopole conductive elements are approximately mutually perpendicular and are disposed so that respective open ends thereof are mutually adjacent, and with respect to a straight line passing between the open ends of the first and second monopole conductive elements and through the center of the conductive ground plane, a first conductive ground plane portion formed on a first monopole conductive element-side of the straight line among the conductive ground plane and the first monopole conductive element are formed so as to be approximately symmetrical to a second conductive ground plane portion formed on a second monopole conductive element-side of the straight line among the conductive ground plane and the second monopole conductive element.