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: 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: An angle diversity antenna system utilizes a first antenna, a second antenna, and a panel combiner coupled to the first and second antenna. In a transmit mode, the first and second antenna are coupled to a transmit sum channel of the panel combiner. In a receive mode, either the sum channel or a difference channel of the panel combiner is chosen as the active channel. By monitoring the sum channel and difference channel, the antenna system according to the present invention is able to select the channel which supplies the greatest signal strength.

Abstract: An improved transmission line for RF communications. A transmission line comprising a center conductor; a dielectric layer surrounding the center conductor; a bimetallic outer conductor including an outer conductive layer and an inner conductive layer; wherein the outer conductive layer and the inner conductive layer are of differing materials; and the inner conductive layer is copper or copper alloy; and an insulating jacket surrounding the bimetallic outer conductor. Other aspects do not require the center conductor or the dielectric layer. Further aspects include a bimetallic center conductor. Advantages of the transmission line include imperviousness to signal loss due to surface abnormalities (due to inner conductive layer being interior to and encapsulated by outer conductive layer); the potential for significant cost savings in material; excellent RF communications signal propagation; and a significant reduction in weight.

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 device for conditioning a signal includes a hybrid phase shifter and power divider. The power divider circuit includes a transmission line with an input port and two asymmetrical output ports, a first ground plane, a second ground plane, and a first dielectric region. The variable phase shifter includes the transmission line and a dielectric slab disposed to be variably positioned in the first dielectric region. The position of the dielectric slab in relation to the power divider circuit determines the amount of phase shift in the signal. With the above configuration, the invention requires much less space and reduces the number of parts and cable interconnects.

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 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 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 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.