Abstract: Rod-shaped multi-band antennas require at least one parallel resonance circuit for separating the individual frequency bands, which consists of a coil and a discrete capacitor. Multi-band antennas of this type for a maximum of three frequency bands are as a rule only suitable for a frequency range from 3 to 30 MHz. In a multi-band antenna (10) suitable for four frequency bands, a first coil (15) is located between a first and a second straight wire piece (14, 16), and a second coil (17) between the second, straight wire section (16) and a third, straight wire piece (18). The first coil constitutes a parallel resonance circuit or a trap circuit, and the second coil a phase shift coil. The multi-band antenna is particularly suited as a vehicle aerial to which a car radio for the AM and FM ranges as well as a mobile telephone for two different nets is connected. The drawing illustrates a rod-like multi-band antenna in accordance with the invention.

Abstract: An elongated rod 11 of dielectric material, for example fiberglass--plastic or the like, has a central conductor (12) located coaxially therein, the conductor having a length L=3/2 .lambda.; in the central .lambda./2 range, the insulating rod is surrounded by a conductive layer (13, 16, 20, 25), for example of conductive lacquer, a mesh or braid of conductive material, a conductive foil or tube or the like. In the lower .lambda./2 region of L1, the bottom terminal of the central conductor will provide a high resistance output for the higher one of the frequency ranges which, for example, can be a radio telephone, or vehicular communication frequency of between 450-470 MHz. The entire antenna is suitable as an AM-FM/radio-telephone combination antenna. .lambda. is the median operating wave length of the higher one of the frequency ranges for which the antenna is suitable. Preferably, the antenna is covered with a sleeve of insulating material, for example a heat shrinkable plastic (27).

Abstract: To permit use of a hand-held transceiver, such as a radio telephone, as a vehicular car telephone, and operation thereof via a car radio receiving antenna (10), an active multi-range antenna switch is connected between the antenna (10), the car radio (27) and the transceiver (29). The antenna is connected to the car radio (27) through a first channel (13) which includes a low-pass filter (15) and an amplifier; the antenna (10) is further connected to the radio telephone via a second channel (14) which includes a high-pass filter (17), an inter-channel modulation suppression filter (18), an amplifier (19) connected to amplify signals from the radio telephone, and a power sensing relay (20) which, when the transceiver (29) is in receiving mode, bridges or shunts the amplifier (19), but opens the switch when the transceiver is in a transmitting mode, to provide amplification of transmission signals from the transceiver or radio telephone.

Abstract: To provide for ominidirectional reception/transmission of slot antennas installed on a vehicle, a plurality of slot antenna units (12, 13, 13a, 14) are installed on the vehicle, facing, for example, forwardly, rearwardly and laterally of the vehicle. Each of the slot antenna units is connected to a common feed point (28) which is coupled to a radio equipment, which may be a transmitter or receiver, by a connecting cable which has a length of n..lambda./2, wherein n is a whole integer and .lambda. is the average operating wave length for which the antenna is designed. For about 500 MHz, an antenna length of about 55 cm with a slot length of 35 cm and a width of about 7 mm is suitable. The antenna can be formed in U shape and function as a license plate holder for, for example, a license plate made of insulating material. The antenna units are insulated from the body of the vehicle.

Abstract: An improved transceiver antenna is designed for mounting on vehicles where, for aerodynamic reasons, vertical orientation is undesirable. It is an object of the present invention to provide a high-gain antenna which, even when mounted at a declination of up to 40.degree. from the vertical, maintains the most smoothly curved possible antenna characteristic. This is achieved by winding four serially connected coils (SP1-SP4) on a rod (12) of dielectric material, with the third coil reverse-wound with respect to the second, with a radiating element (13) connected to the free end of the fourth coil, the lengths of the coils and radiating element being selected to be, respectively, 1/4, 1/4, 1/8, 1/8, and 3/8 of the median wavelength. Upon mounting at an angle of 40.degree. to the vertical, this antenna has an optimal antenna characteristic curve.

Abstract: To provide a single antenna suitable both for VHF as well as UHF television (TV) reception, without changing the length of the antenna, a core support rod (11) of, for example, flexible plastic material is resiliently coupled at one end to a connection terminal (29). Wound on the rod are two connected windings (12, 13), one of them being spiralled with wide spiral turns about the core support rod (11) throughout the major length of the antenna, the other winding (13) being wound closely or tightly thereabout. The two windings are capacitatively coupled by a turn or loop (17) of a third winding (18), pushed between the two last turns (15, 16) of the third winding (13) and electrically connected to the connection terminal (29). The distance (1.sub.1) between the third winding (18) and the connection terminal (29) is .lambda..sub.U /4, the distance between the end of the first winding (12) and the terminal is .lambda..sub.U /4, and which .lambda..sub.U and .lambda..sub.

Abstract: To provide a short FM antenna, of about for example 40 cm length for mobile radio, for example automobile radio application, without degradation of signal strength with respect to an about 1 m long FM antenna, a conically tapering insulating rod, for example of fiberglass, has two windings applied thereover, the two windings, each, having a straight wire length of about 1/4 the median wavelength of the FM band, and the overall length (l) of the rod having said two windings applied thereover being about 1/8 of the median wavelength. The oppositely wound windings (11, 12) are connected at their center, and may be formed as one bifilar winding, with the lower end of the lower winding being connected to an electrical terminal for standard connection to, for example, a coaxial antenna connector for an automobile radio.