Antenna for the reception of circularly polarized satellite radio signals for satellite navigation on a vehicle

An antenna for the reception of circularly polarized satellite radio signals, wherein the antenna comprises at least one horizontally oriented conductor loop arranged over a conductive base surface, comprising an arrangement connected to an antenna connector for the electromagnetic excitation of the conductor loop,

• wherein the conductor loop is formed as a ring line radiator by a polygonal or circular closed ring line in a horizontal plane having a height and extending over the conductive base surface;
• wherein the ring line radiator forms a resonant structure and is electrically excitable by electromagnetic excitation in a manner such that the current distribution of a propagating line wave is adopted on the ring line in a single revolving direction whose phase difference over one revolution amounts to 2π;
• wherein radiators that are galvanically coupled to the ring line radiator, that are vertical, and that extend toward the conductive base surface are present at ring line coupling points at the periphery of the ring line radiator, with one of the radiators being configured as an active radiator via which the excitation of the conductive loop takes place and the other radiators being coupled as vertical passive radiators to the electrically conductive base surface;
• wherein at least two vertically passive radiators are present which are galvanically coupled to the ring line radiator and extend toward the conductive base surface and of which N vertical passive radiators are coupled via a reactance circuit having an active component to the electrically conductive base surface, with the loss factor of the active component respectively being larger than the value 0.1/N;
• wherein two of these vertical passive radiators are not arranged adjacent to one another at any point along the ring line radiator;
• wherein all the remaining passive vertical radiators are coupled via lossless reactance circuits to the base surface;
• and
• wherein none of the spacings between mutually adjacent ring line coupling points is smaller at the periphery of the ring line radiator than half the spacing that would result with an equidistant distribution of all the radiators over the stretched length of the ring line radiator.