Abstract: A loop antenna able to be mounted on the rear window of a vehicle provided with a defogger, that is, a loop antenna to be mounted on a rear window provided with a defogger having electrodes arranged in the vertical direction at the two ends and a plurality of electrical heating wires bridging the electrodes in the horizontal direction, wherein an antenna element forming a loop is made polygonal in shape, two power feed terminals of the loop antenna are provided at positions a predetermined distance away from the midpoint of the bottom of the antenna element, constituted by one side, in the vertical direction, a distance between the power feed terminals and bottom is formed smaller than the distance between adjoining electrical heating wires of the defogger, and the loop antenna is mounted on the rear window between the adjoining electrical heating wires. The polygonal shape may be a triangular shape.

Abstract: When configuring a film antenna for receiving a circular polarized wave, at least one loop antenna is formed on a transparent plastic film and, at the same time, a non-powered element constituted by a wire-shaped conductor independent from the antenna conductor configuring the loop is arranged near this loop antenna. The non-powered element arranged on the side of the loop antenna is configured by a first part and a second part. The first part is made close to the loop antenna in a substantially parallel state. When a monopole antenna is used in place of the loop antenna, by combining this with a wire-shaped conductor orthogonal to this, it becomes possible to receive a circular polarized wave by a configuration providing a power transfer part between the two. It is also possible to configure a composite antenna by mounting another antenna on the transparent plastic film. This antenna can be used as an antenna of a navigation system.

Abstract: A loop antenna able to be mounted on the rear window of a vehicle provided with a defogger, that is, a loop antenna to be mounted on a rear window provided with a defogger having electrodes arranged in the vertical direction at the two ends and a plurality of electrical heating wires bridging the electrodes in the horizontal direction, wherein an antenna element forming a loop is made polygonal in shape, two power feed terminals of the loop antenna are provided at positions a predetermined distance away from the midpoint of the bottom of the antenna element, constituted by one side, in the vertical direction, a distance between the power feed terminals and bottom is formed smaller than the distance between adjoining electrical heating wires of the defogger, and the loop antenna is mounted on the rear window between the adjoining electrical heating wires. The polygonal shape may be a triangular shape.

Abstract: When configuring a film antenna for receiving a circular polarized wave, at least one loop antenna is formed on a transparent plastic film and, at the same time, a non-powered element constituted by a wire-shaped conductor independent from the antenna conductor configuring the loop is arranged near this loop antenna. The non-powered element arranged on the side of the loop antenna is configured by a first part and a second part. The first part is made close to the loop antenna in a substantially parallel state. When a monopole antenna is used in place of the loop antenna, by combining this with a wire-shaped conductor orthogonal to this, it becomes possible to receive a circular polarized wave by a configuration providing a power transfer part between the two. It is also possible to configure a composite antenna by mounting another antenna on the transparent plastic film. This antenna can be used as an antenna of a navigation system.