144 results about "Whip antenna" patented technology

An antenna means for a portable radio communication device, in particular a hand-portable mobile telephone, having at least one radiating element that has a meandering and cylindrical configuration. This structure is specifically advantageous in combination with an extendable and retractable whip antenna and, when having two or more meandering radiating elements, in multi-band radiating structures. The antenna device is suitable for manufacturing in large quantities, for example by a flexible printed circuit board technique.

An antenna assembly for a portable radio device/mobile station is provided. The assembly includes a retractable whip antenna 24, a first radio lead 50 for coupling the whip antenna to a mobile telephony receiver, and a second radio lead 48 for coupling the whip antenna 24 to a FM or DVB receiver. Each lead is coupled to the whip antenna at least when the whip antenna is fully extended. In one embodiment, received signals are frequency discriminated by a RF choke such as an inductor 52 along the second radio lead. In another embodiment, the first radio lead is coupled directly to a PIFA antenna 58 internal to the portable device, and the whip antenna is in parasitic communication 64 with the PIFA antenna at least when the whip antenna is extended and receiving signals above a threshold frequency. In that alternative embodiment, the whip antenna is preferably decoupled from ground.

A retractable whip antenna incorporating a matching base loading helix for use in mobile communications devices is disclosed. The antenna functions without the use of a matching circuit since selection of the radiating elements provides a constant input impedance to the transceiver circuitry. The resulting antenna provides excellent gain over the PCS frequency band, low SAR values, circuit design flexibility and low cost. In a preferred embodiment, the retractable whip is comprised of a radiating element with an electrical length of +E,fra 1/2+EE wavelength and having a first end attached to a conductive spring contact. The base loading helix comprises a radiating helical element with an electrical length of +E,fra 1/4+EE wavelength and having a first end connected to a mobile transceiver circuit and a second end comprising a conductive capturing coil. The radiating whip element is constrained within the coil of the helical element and is freely moveable to an extended or a retracted position. When the whip element is in the retracted position, the whip element is disconnected from the radiating circuit. When the whip element is in an extended position, an electrical connection is formed via contact between the conductive spring contact and the conductive capturing coil, wherein the helical element effectively base loads the whip element so that the two radiating elements have a combined electrical length of +E,fra 3/4+EE wavelength.

A coaxial antenna is implemented that combines a VHF and UHF antenna on a common radiating element. The antenna may further include a satellite antenna that, together with the VHF/UHF antenna fits into a whip antenna footprint.

A portable radio apparatus capable of providing an impedance match with an antenna and a simple matching circuit for all frequency components of a frequency band to be used. A portable radio apparatus includes a whip antenna, a matching circuit, a radio section changing switch, a first frequency band receiver, and a first frequency band transmitter. A parallel inductor causing a resonance with a frequency lower than a resonance frequency of the antenna is connected in parallel to the antenna for a two-resonance characteristic to thereby conduct a wide-band operation.

The present invention provides a direction finder antenna that includes an antenna mount having one flat portion and four extensible whip antenna elements respectively upright provided rotatably at antenna upright-provided points formed on one circumference at an antenna upright-provided surface. The four extensible whip antenna elements can be rotatably set to arbitrary angular positions lying in sector-shaped areas each having an open angle of 180° orthogonal to the one circumference, which are formed on the antenna upright-provided surface side, centering on the respective antenna upright-provided points at the antenna upright-provided surface.

A multi-band whip antenna having a 30 MHz to 2 GHz bandwidth and an L-band dipole has its coverage extended up to 6 GHz by eliminating nulls and reducing VSWR problems that are cured through the utilization of a sleeve over the feedpoint of the L-band antenna. Chokes in the form of sleeves are provided at either end of the L-band dipole to shorten the L-band antenna for preventing reverse polarity currents at the L-band antenna feedpoint, with the antenna further including the use of double shielded meanderlines to provide improved performance between 410-512 MHz and in which a capacitance sleeve is added at the bottom of the L-band antenna to effectively elongate the antenna below the L-band to permit operation below 700 MHz.

A communication device is presented that has an antenna structure with a relatively short length and covers multiple resonances including the UHF and the GPS bands. The antenna structure has a conductive base to which a whip antenna is connected through a helical radiating element. A cylindrical sheath capacitively connected to the helical element provides distributed impedance matching for the antenna structure. A monopole or another helical element provides higher resonance than that of the whip antenna or connected helical element. If the higher resonance is provided by a monopole, the monopole is disposed radially adjacent to the helical element and is capacitively connected with the helical element through an opening in the sheath. If the higher resonance is provided by a helical element, the helical element is capacitively or galvanically connected to the end of the whip antenna.

The present invention involves a tracking antenna system with no moving parts that extends the range of wireless mobile links 16 to 256 times the range of regular omni-directional whip antennas. The antenna system comprises an array of antenna segments arranged in a sphere or circle, or other suitable geometry. Each antenna segment includes one or more antennas connected and combined in parallel. Each antenna segment feeds a tuner and subsequent diversity electronics that optimizes both the transmission and reception in order to achieve the best possible range. The antenna system can be used from unmanned air, ground, and surface vehicles to mobile ground stations in motion, as well as between flying planes, moving vehicles, sailing boats, or any combination thereof. The system may be expanded further to many more levels of architecture as required. For example, this system may be expanded to a Level 2 diversity engine combination of any number and type of Level 1 antenna array units depending upon the diversity expansion required and the criteria for Level 2.

The invention provides a 30MHz-512MHz multi-band 2.5m whip antenna, which mainly solves the impedance matching problem between the antenna and the radio station. The entire antenna includes: a radiator, a coaxial cable 18, and a base 6. The radiator adopts a combined structure of a lower radiator 7 and an upper radiator 5. The lower radiator includes a lower copper tube 1 and an upper copper tube 3, two copper tubes The tubes are connected by a transmission line transformer 2, and a radiation oscillator 4 is fixed in the upper copper tube to form a sleeve antenna structure. The transmission line transformer adopts a three-winding center tap, and is equipped with four coils, which are respectively connected to the inner conductor, outer conductor, upper section copper tube, and lower section copper tube of the coaxial cable. It is used as both an electronic switch and an impedance matching element. Ultra-wideband characteristics in the 30MHz~512MHz frequency band. The invention has the advantages of wide frequency band, small standing wave ratio, high gain, no need for tuning, and can be directly matched with radio stations, and is suitable for installation on various armored vehicles and ships.

The present invention provides systems and methods that facilitate transmission and/or reception of radio frequency (RF) signals within a mobile communications device. The systems and methods include a first antenna component such as an active stub that comprises one or more active elements and a second antenna component such as a parasitic whip that is electromagnetically coupled to the first antenna component. The systems and methods provide a relatively compact antenna structure for mobile devices with limited physical volume, or footprint. The antenna structure does not require a mechanical interface (e.g., a galvanic connection) between the active stub and parasitic whip to provide a conductive connection to the whip when it is in an extended position. The novel systems and methods yield reduced antenna wear, higher antenna gain and better radiation efficiency than conventional systems and do not require a matching circuit to achieve multi-band resonances.

A coaxial antenna is implemented that combines a VHF and UHF antenna on a common radiating element. The antenna may further include a satellite antenna that, together with the VHF/UHF antenna fits into a whip antenna footprint. The antenna incorporates chokes that may be implemented using meanderline techniques.

A standard slow wave meander line having sections of alternating impedance relative to a conductor plate is provided with a top shield connected to the conductor plane for the purpose of lowering the resonant frequency of narrow band antennas and lowering the low frequency cutoff limit of wide band antennas due to a higher delay per unit length occasioned by the use of the top shield. The shielded meander line may be utilized as a coupling device to truncated antennas such as a whip antenna or grounded loop antenna for the purposes of loading the antenna so as to provide lower frequency performance. Since the propagation constant of the meander line structure depends upon the number of high impedance/low impedance transitions per unit length, the utilization of the top shield results in more phase shifts per unit length and thus more delay per unit length, with the symmetric double sided version having double the number of transitions per unit length. When configured to provide a miniature antenna, the utilization of the top shield both lowers the cutoff frequency and eliminates down firing typical of wireless phone antennas due to the ground plane effect. Moreover, the top shield provides a uniform low VSWR over wide bandwidths and by virtue of lowering the operating frequency solves a skip-induced blackout problem due to the lower frequencies that can now be used. Further, for frequency switched meander lines, voltage stress is reduced when using the top shield. Finally, reducing the volume requirement by over 30% permits mobile use where real estate is at a premium.

The invention provides a shortwave antenna tuning system comprising a shortwave whip antenna, an antenna adapter, a multi-path coupler and a multi-channel receiver. The multi-channel receiver comprises a receiving channel, a channel digital signal processing module, a frequency synthesizer module, a main control module, a front panel module, a power supply module, and a cabinet with a CPCI bus. The receiving channel receives shortwave radio frequency signals and carries out mixing, filtering and amplifying processing on the signals. The frequency synthesizer module provides a standard frequency signal needed by the channel digital signal processing module and provides and outputs a local oscillation signal to the receiving channel at the same time. The shortwave signal is converted into a high and medium frequency signal through mixing, and a 16-bit A/D is used to carry out analog to digital conversion in the channel digital signal processing module. At the same time, the channel digital signal processing module is connected with the antenna adapter and the multi-path coupler by using serial ports, the received shortwave radio frequency signals are outputted to the multi-path coupler through adjusting the matched impedance by the antenna adapter, and the multi-path coupler outputs the signals to the multi-channel receiver.