Abstract: A multi-frequency antenna apparatus includes an open-ended slot antenna (20) operable at high frequencies, cascaded in series with a antenna element (22) operable at low frequencies, results in two distinct antennas fed by a single excitation port (33). A U-shaped conductive strip (21) defining the slot antenna (20) has a ground connection (37) at one end near the open-ended side of the slot antenna (20) and a virtual feed point (30) on the other end coupled to the antenna element (22). The electrical length from the ground connection (37) to the feed point is about ¼ of a wavelength of the first frequency creating a virtual open at the feed point (30).