A shielded antenna (100) includes a spiral antenna (110) and a shield (120) disposed on the spiral antenna. The spiral antenna comprises a plurality of substantially concentric loops. The shield comprises a plurality of electrically isolated electrically conductive segments forming a regular pattern, such that in a top plan view, at least one segment overlaps a portion of at least two loops, and at least one pair of adjacent conductive segments defines an electrically insulative gap therebetween.