Abstract: The dual band bi-directional amplifier has only one amplifier chain having an uplink amplifier and a downlink amplifier, but can nonetheless amplify signals from two frequency bands in both an uplink and a downlink direction between two antennas. This is possible by using duplexers and circulators to separate signals to and from each antenna into the two bands. In particular, for each frequency band handled by the circuit, the dual band bi-directional amplifier has a duplexer set for separating the signals from one of the bands into the uplink and downlink direction. In the case of a dual band amplifier, there are two sets of duplexers, one for each band. By using duplexers and circulators to differentiate signals in different bands travelling in different directions, there is no need for additional amplifier chains, which increase the manufacturing costs.

Abstract: The present invention is directed to a novel foamed polymer material for use as a dielectric in electric transmission lines. The foam dielectric of the present invention is obtained from extrusion of a polymer alloy and a supercritical fluid, especially carbon dioxide. Specifically, the foam polymer dielectric is made by: (1) feeding a polymer alloy into an extruder and heating the polymer alloy, (2) feeding a supercritical fluid into the extruder, (3) mixing the polymer alloy and the supercritical fluid, (4) exiting the polymer alloy and the supercritical fluid from the extruder, and (5) passing the polymer alloy and the supercritical fluid through a crosshead. The foam dielectric of the present invention may be used in coaxial transmission lines. In this embodiment, an inner conductor is surrounded by the foam dielectric, which is further surrounded by a second conductor. Stripline and microstripline transmission lines may also be manufactured using the disclosed foam dielectric.

Abstract: A hybrid filter assembly is provided having a first ceramic triple-mode mono-block resonator, a second ceramic triple-mode mono-block resonator and at least one metallic resonator coupled to at least one of the first and second mono-block resonators. Each triple-mode mono-block resonator supports three resonant modes and each metallic resonator supports an additional mode, thereby providing a hybrid filter assembly of reduced size having more than six poles.

Abstract: A tuned RF coaxial connector for mating a coaxial transmission line includes a cylindrical outer conductor, a coupling mechanism for mating the coaxial transmission line to the substantially cylindrical outer conductor, and an inner conductor extending coaxially within cylindrical outer conductor. One end of the cylindrical outer conductor interfits with the coaxial transmission line and another end of the cylindrical outer conductor interfits with an electrical device. The connector has an open circuit inner stub where the inner conductor of the transmission line couples to the inner conductor of the connector, or an open circuit outer stub where the outer conductor of the transmission line couples to the outer body of the connector, or both. Without the need for precise fitting of the conductors of the coaxial transmission line and the connector, the invention facilitates field installation of cables and connectors while reducing implementation cost.

Abstract: A frequency selective low loss transmission system for communicating a signal using a coaxial cable of one impedance to a device of different impedance. A connector with a matching transformer is integral to the connector which terminates with a standard interface. The invention also includes a coupling mechanism to couple the coaxial cable with the connector. The invention can also include series open stub conductors for capacitive coupling to the conductors of the coaxial cable. In addition to low losses over a broad frequency range, the connector facilitates connector installation due to the series open stub conductor while reducing cost and complexity of both coaxial cable and connector.

Abstract: The present invention incorporates triple-mode, mono-block resonators that are smaller and less costly. The size reduction has two sources. First, the triple-mode mono-block resonator has three resonators in one block. This provides a 3-fold reduction in size compared to filters currently used which disclose one resonator per block. Secondly, the resonators are not air-filled coaxial resonators as in the standard combline construction, but are dielectric-filled blocks. The coupling between modes is accomplished by the corner cuts. One oriented along the Y axis and one oriented along the Z axis. In addition, a third corner cut along the X axis can be used. Corner cuts are used to couple a mode oriented in one direction to a mode oriented in a second mutually orthogonal direction. Each coupling represents one pole in the filter's response. Therefore, the triple-mode mono-block discussed above represents the equivalent of three poles or three electrical resonators.

Abstract: A cavity filter which provides for fine tuning of the bandwidth of the filter. The filter provides for both capacitive cross-coupling and inductive coupling between physically adjacent but electrically non-adjacent resonators in the filter. The isolation of the filter can be fine tuned by adjusting the inductive coupling between these resonators, which has the effect of attenuating the cross-coupling effect between these resonators.

Abstract: A novel junction design was developed for use with in-line combiner networks to minimize electrical length between the resonators being combined and to optimize coupling. It consists of a combiner comprising a plurality of cavity resonators coupled to a combining mechanism. The combining mechanism is placed outside of each resonator a prescribed distance above the ground plane. Combiner pairs are created by connecting two cavities to each other using quarter-wave lines. The central combiner pair is directly connected to the output connector through a common port. The quarter-wave junctions not directly connected to the output connector are then connected to the output port through half-wavelength lines. Iris or aperture coupling is controlled by a sliding cover that is adjusted using a free-rotating screw and is secured with locking screws to ensure good electrical and RF grounding.

Abstract: The invention is related to the field of tunable multiplexers. It consists of a tunable microwave multiplexer comprising a plurality of channel filters coupled to a combining/dividing mechanism. The plurality of channel filters can be either dielectric loaded resonators or combline resonators, while the combining/dividing mechanism can be a common resonator. In one embodiment, the common resonator is a multiple half-wavelength coaxial resonator.

Abstract: A polarized antenna for sending and receiving polarized radio frequency signals is disclosed which includes a dipole and a reflector plate. The dipole is formed as a single part including the radiating arms and feeding structures, thereby requiring minimum assembly. This dipole can be formed by molding conventional materials, such as copper, aluminum, and plastic, which can then be plated. The feeding structure through which the cable passes features a slotted aperture. The impedance of the dipole is based on the width of these apertures and the size of the cable conductor. By having a single-body construction, the dipole of the present invention provides, good impedance, low intermodulation distortion, good port-to-port isolation, and good pattern purity.

Abstract: A waveguide structure that has two rotating parts changes the polarization of a radio frequency signal in two steps or one step. The waveguide structure includes input and output waveguides and a polarization rotator. The output waveguide includes two cavities corresponding to two polarizations. The rotator includes cut-away portions of a rectangular shape which are rotated with respect to each other and the first wave guide by predetermined angles. When the second waveguide is rotated from one cavity to another, the rotator is also rotated, thereby changing the polarization of the signals passing through the waveguide. In addition, if the rotator and the second waveguide are interlocked, then the number of steps required to accomplish the polarization change can be reduced to one, because rotation of the second waveguide will cause the rotation of the polarization rotator.

Abstract: A novel locking mechanism for mounting a radio to an antenna. The mounting face of a radio is secured to the mounting portion of an antenna. The mounting portion of the radio has a locking ring on which a plurality of radio locking tabs are located at equally spaced positions. The ring can be fixed to the radio, or in another embodiment, is still secured to the radio but can rotate independently. The mounting portion of the antenna has a corresponding number of equidistantly spaced tension springs, which have a plurality of spring fingers. To mount the radio to the antenna, the radio locking ring with radio locking tabs is twisted so that each antenna tension spring is deflected by a corresponding radio locking tab. The engagement of the radio locking ring to the antenna spring fingers secures the radio to the antenna. The deflection force also produces a friction force.

Abstract: An antenna control system is connected to an antenna in order to control the position of the antenna. The system includes a motor connected to the antenna for adjusting the position or vertical tilt angle of the antenna. A driver is provided for operating the motor. A sensor is also provided to detect the position of the antenna. In addition, an antenna controller is connected to an antenna memory, the driver, and the sensor, for reading the detected position of the antenna and for controlling the driver to adjust the antenna's position. A main controller is connected to the antenna controller for sending commands to and reading data from the antenna controller. In this manner, the main controller can interface with any number of antennas at a base station and control the position or down-tilt of each antenna. According to one embodiment of the control system, a user interface is also provided for entering commands to and reading data from the main controller.

Abstract: A system for inductively cross coupling resonators. Two resonators are interconnected by a cross coupler with the two ends, each end having a hole. The holes secures each end of the cross coupler to one of the resonators. The use of a stamped piece as a cross coupler results in a repeatable placement between resonators that minimizes any variation in coupling between resonators due to human error during assembly. This repeatability reduces assembly time and assembly cost.

Abstract: This invention relates to an improved coaxial cable preparation tool (1) that is used to prepare a coaxial cable terminal end for connector installation. The tool comprises two stages. The first stage, the jacket stripper, is used to trim the cable jacket. The second stage (20), the cable trimmer, is used to trim the remaining center, the outer conductors and the foam insulation of the coaxial cable. The first stage (10) consists of a cup or cylinder (11) with an outer cylindrical wall (12). In addition, it also comprises a blade (13) and a scrap port (14). In addition, the first stage cylinder (11) has a bore (16) extending axially down its center. The diameter of the bore (16) is set to receive a coaxial cable. The second stage consists of a hub (21) (or cutter head), a collet bearing (22) and a body (23). In addition, like the first stage, it also contains blades (13) and scrap ports (14). The scrap ports or debris ports (14) allow trimmed cable media to escape from the bores in the tool.

Abstract: A microwave coupler has a planar form with a transmission line segment oriented at an angle relative to a main transmission line. The planar form of the transmission line, such as in a printed circuit board, helps reduce the size and manufacturing costs for the coupler. When placed a prescribed distance from the main transmission line and oriented at an appropriate angle, the directivity and coupling factor requirements can be met precisely with minimal tuning. Where fine tuning is required, a tuning screw and resistor disposed adjacent to the transmission line segment are provided.

Abstract: A multi-channel multiplexer has a substantially square shape and includes an N×N matrix with a common resonator. A plurality of input/output ports are connected to a common input/output port via respective resonators of the N×N matrix and the common resonator. The multiplexer provides a compact size, with balanced insertion losses and simple configuration to minimize phase difference of inter-resonator transitions.

Abstract: A tunable, temperature compensated, thermal and mechanical stable, dielectric loaded cavity resonator and filter assembly has high unloaded Q, wide frequency tuning range and simple structure suitable for high volume production. The cavity resonator consists of a conductive housing, a substantially cylindrical ring shape dielectric body with a low loss, low thermal expansion coefficient support, a tuning mechanism and a plastic support at the opposite side of the main cylindrical dielectric body, which holds the main cylindrical dielectric body in place. The tuning mechanism further includes a substantially cylindrical dielectric tuning element positioned in or near the hole of the main cylindrical dielectric body and a self-locked or equivalent nut locked rotor with a support using the same material as that of the main cylindrical body support.

Abstract: This invention relates to a tapered slot antenna with broadband characteristics whose beamwidth is stable over both the PCS (1850-1990 MHz) and the cellular bands (824-894 MHz). In a first preferred embodiment, a dual band antenna is disclosed which uses a single column elliptically shaped Vivaldi notches as the radiating elements. In a second preferred embodiment, a dual band antenna comprising elliptically shaped Vivaldi notches and sub-reflector positioned between a main reflector and the dipoles is disclosed. This resultant antenna produces a stable, ninety-degree beamwidth with a bandwidth broad enough to cover the PCS and the cellular bands.

Abstract: This invention relates to an improved coaxial cable preparation tool (1) that is used to prepare a coaxial cable terminal end for connector installation. The tool comprises two stages. The first stage, the jacket stripper, is used to trim the cable jacket. The second stage (20), the cable trimmer, is used to trim the remaining center, the outer conductors and the foam insulation of the coaxial cable. The first stage (10) consists of a cup or cylinder (11) with an outer cylindrical wall (12). In addition, it also comprises a blade (13) and a scrap port (14). In addition, the first stage cylinder (11) has a bore (16) extending axially down its center. The diameter of the bore (16) is set to receive a coaxial cable. The second stage consists of a hub (21) (or cutter head), a collet bearing (22) and a body (23). In addition, like the first stage, it also contains blades (13) and scrap ports (14). The scrap ports or debris ports (14) allow trimmed cable media to escape from the bores in the tool.