Abstract: A multiplexer circuit for CB, AM/FM, and television splits the radio and television signals, adding impedance to the split lines, and providing an amplifier upstream of the split.

Abstract: A mobile antenna includes a center-fed, broadband, dipole radiator, and a coupler assembly for mounting the dipole radiator to a mount. A power matching circuit is connected between the dipole radiator and the coupler assembly to maintain an effective balance of current distribution and impedance in conductive elements of the antenna.

Abstract: A multiband antenna has a dipole radiator that resonates in a lower frequency band, and a stacked dual dipole radiator that resonates in a higher frequency band. An isolation circuit, tuned to block signals in the higher frequency band, is connected between one end of the stacked dual dipole radiator and the lower frequency dipole radiator to isolate the higher frequency band from the lower frequency band.

Abstract: A multiband antenna has a lower radiator and several upper radiators, all of which are spaced from each other and disposed on the same longitudinal axis. The lower radiator and the upper radiators form a dipole radiator that resonates in a lower frequency band. The upper radiators form a dipole radiator that resonates in a higher frequency band. Multiple isolation circuits in the upper radiators resonate at different frequencies within the lower frequency band.

Abstract: A multiband antenna has a lower conductive tube and three or more upper conductive tubes, all spaced from each other and disposed on the same longitudinal axis. A transmission line extends within the lower conductive tube to a first feed point and a second transmission line extends within the lower conductive tube and one or more of the upper conductive tubes to a second feed point. The lower and upper conductive tubes form a dipole radiator centered on the first feed point. The upper conductive tubes form a dipole radiator centered on the second feed point. One or more isolation circuits resonate in only one frequency band for signals transmitted along one of the transmission lines.

Abstract: A multiplexer circuit adapted to receive standard cellular telephone signals and PCS signals without user intervention comprises two filter circuits. The first filter circuit presents a high impedance to signals outside the standard cellular frequency range from one antenna and the second circuit presents a high impedance to signals outside the higher PCS frequency range from a second antenna. A cell phone adapted to receive both frequency ranges will automatically detect the appropriate signal.

Abstract: A multiplexer circuit adapted to receive signals comprises two filter circuits. The first filter circuit presents a high impedance to signals outside a first frequency range and the second circuit presents a high impedance to signals outside a second frequency range. Isolation matching circuits enable transmission and reception of one of the signals in the first or second frequency ranges without degradation or interference with the other range. An embodiment allows transmission and reception of satellite Orbcomm frequencies over a standard AM/FM antenna without effect on the AM/FM signal.

Abstract: An AM/FM/WB/CB/cellular telephone antenna includes a first frequency self-resonant circuit at a position above the lower end of the antenna such that the electrical length of the lower section of the antenna is equivalent to one-quarter wavelength for a frequency in the FM frequency range and a second frequency self-resonant circuit disposed below the first frequency self-resonant circuit. The first self-resonant circuit presents a high impedance in the FM frequency band and the second self-resonant circuit presents a high impedance in the cellular frequency range. The entire length of the antenna is equivalent to one-quarter wavelength in a frequency in the CB frequency band. The antenna wire is wound around a fiberglass core, and the FM self-resonant circuit is formed by a tightly wound, coiled section of the wire together with a thin-walled brass tube extending over the core in the area of the tightly wound section.

Abstract: An AM/FM/CB/cellular telephone antenna includes a first frequency self-resonant circuit at a position above the lower end of the antenna such that the electrical length of the lower section of the antenna is equivalent to one-quarter wavelength for a frequency in the FM frequency range and a second frequency self-resonant circuit disposed below the first frequency self-resonant circuit. The first self-resonant circuit presents a high impedance in the FM frequency band and the second self-resonant circuit presents a high impedance in the cellular frequency range. The entire length of the antenna is equivalent to one-quarter wavelength in a frequency in the CB frequency band. The antenna wire is wound around a fiberglass core, and the FM self-resonant circuit is formed by a tightly wound, coiled section of the wire together with a thin-walled brass tube extending over the core in the area of the tightly wound section.

Abstract: An AM/FM/CB/cellular telephone antenna includes a first frequency self-resonant circuit at a position above the lower end of the antenna such that the electrical length of the lower section of the antenna is equivalent to one-quarter wavelength for a frequency in the FM frequency range and a second frequency self-resonant circuit disposed below the first frequency self-resonant circuit. The first self-resonant circuit presents a high impedance in the FM frequency band and the second self-resonant circuit presents a high impedance in the cellular frequency range. The entire length of the antenna is equivalent to one-quarter wavelength in a frequency in the CB frequency band. The antenna wire is wound around a fiberglass core, and the FM self-resonant circuit is formed by a tightly wound, coiled section of the wire together with a thin-walled brass tube extending over the core in the area of the tightly wound section.

Abstract: A combined AM/FM/cellular telephone antenna system comprises a coaxial cable with an upper portion of the inner conductor of the coaxial cable and an adjacent section of the coaxial cable together forming a cellular telephone dipole antenna. The coaxial cable forms a transmission line connecting the cellular dipole antenna to cellular telephone equipment. The outer conductor of a portion of the coaxial cable below the cellular dipole antenna serves as the AM/FM antenna. The combined antenna is encaged in a fiberglass housing and mounted on a metallic base having an upper shell and a lower shell. The upper shell is electrically connected to the outer conductor of the coaxial cable forming the antenna and the lower shell is connected to a ground plane. A coaxial cable having a center conductor connected to the upper shell and an outer conductor connected to the lower shield provides connection to AM/FM receiver equipment.

Abstract: A television antenna is constructed of a flat plate antenna comprising a plurality of concentric, rectangularly shaped loops formed of conductive material and disposed on a substrate. Each loop forms an antenna for signals in a predefined frequency band within the TV frequency spectrum. An additional loop is disposed within the plurality of concentric loops and is adapted for receiving signals in the FM frequency range. Each of the loops has four sides having an electrical length equivalent to one-quarter wavelength at a center frequency within a frequency band and each side of each antenna loop is connected to a side of another antenna loop and to one of a pair of antenna output terminals. The sides of each loop are formed by conductive strips deposited on a dielectric substrate which is particularly adapted for installation adjacent a dielectric roof panel or the like.

Abstract: An antenna module for use a non-conductive cab of a motor vehicle includes a dielectric substrate and one or more antenna loops arranged on the substrate. The substrate is adapted to be installed between the headliner of a cab and the dielectric roof. The module may include a CB antenna loop, an AM/FM antenna loop, a cellular mobile telephone antenna loop, and a global positioning system antenna, without the need for any antenna structure external to the cab. The antennae are arranged on the module in a nested configuration. A CB antenna, provided with loading coils, forms an outer loop. An AM/FM antenna loop, including a capacitor yielding a substantially short circuit connection in the FM frequency range, forms a FM frequency antenna loop and an AM frequency dipole, within the CB loop. A multiloop array cellular telephone antenna is arranged within the AM/FM loop. A standard crossed dipole GPS antenna is positioned in an area between the CB loop and the AM/FM loop near one corner of the substrate.