Abstract: A wireless communications device reconfigurable radiation desensitivity bracket, and associated reconfigurable radiation desensitivity method are provided. The method includes: generating a radiated wave at a first frequency; in response to generating the radiated wave at the first frequency, creating a maximum current per units square (I/units2) through a minimal area of an electrical circuit groundplane; generating a radiated wave at a second frequency; in response to generating the radiated wave at the second frequency, maintaining the maximum I/units2 through the minimal area of the groundplane. Alternately stated, the method controls the distribution of current flow through a groundplane, responsive to radiated emissions, as the wireless device changes operating frequency or communication band. More specifically, the method maintains the maximum I/units2 through the minimal area of the groundplane by coupling the groundplane to a bracket having a selectable effective electrical length.

Abstract: A capacitively-loaded loop antenna and corresponding radiation method have been provided. The antenna comprises a transformer loop having a balanced feed interface and a capacitively-loaded loop radiator. In one aspect, the capacitively-loaded loop radiator is a balanced radiator. In another, the transformed loop and capacitively-loaded loop radiator are physically connected. That is, the transformer loop and the capacitively-loaded loop radiator have a portion shared by both of the loop perimeters. Alternately, the loops are physically independent of each other. In one aspect, the perimeters have a rectangular shape. Other shapes such as round or oval are also possible. In another aspect, the planes formed by the transformer and capacitively-loaded loop radiator can be coplanar or non-planar, while both loops are orthogonal to a common magnetic near-field generated by the transformed loop.

Abstract: A multiple band capacitively-loaded magnetic dipole antenna includes a plurality of magnetic dipole radiators connected to a transformer loop where the magnetic dipole radiators include at least one capacitively-loaded magnetic dipole radiator. The transformer loop has a balanced feed interface and includes a side that provides a transformer interface of quasi loops formed by the plurality of magnetic dipole radiators. Each quasi loop has a configuration and length to maximize antenna performance within a different frequency band. The at least one capacitively-loaded magnetic dipole radiator may be formed with a meander line structure and may include an electric field bridge such as a dielectric gap, lumped element, circuit board surface-mounted, ferroelectric tunable, or a microelectromechanical system (MEMS) capacitor.

Abstract: A cellular modem card that conforms to a PCMCIA standard includes a balanced antenna. The balanced antenna minimizes susceptibility to limited available ground plane and limited ground connections between the modem card and a host device, such as laptop computer. The balanced antenna may be a dipole antenna, loop antenna, capacitively loaded antenna, or any other suitable balanced antenna.

Abstract: A capacitively-loaded loop antenna and corresponding radiation method have been provided. The antenna comprises a transformer loop having a balanced feed interface and a capacitively-loaded loop radiator. In one aspect, the capacitively-loaded loop radiator is a balanced radiator. In another, the transformed loop and capacitively-loaded loop radiator are physically connected. That is, the transformer loop and the capacitively-loaded loop radiator have a portion shared by both of the loop perimeters. Alternately, the loops are physically independent of each other. In one aspect, the perimeters have a rectangular shape. Other shapes such as round or oval are also possible. In another aspect, the planes formed by the transformer and capacitively-loaded loop radiator can be coplanar or non-planar, while both loops are orthogonal to a common magnetic near-field generated by the transformed loop.

Abstract: An apparatus, system, and method dynamically adjust an antenna network frequency response in accordance with an operation mode of a half duplex call. One of a plurality of antenna network configurations is selected based at least partly on the half duplex operation mode which comprises a talk mode and a listen mode. When the portable communication device is in a listen mode, the antenna network is tuned to a reception configuration which results in a reception efficiency that is greater for at least a portion of a reception frequency band than the reception efficiency resulting from at least one other antenna network configuration. The antenna network is maintained in a default configuration unless antenna adjustment conditions are met. In some situations, the antenna network is set to a transmission configuration to improve transmission efficiency relative to the default configuration.

Abstract: A system and method is provided for tuning a Global Positioning System (GPS) antenna matching circuit in a portable wireless communications device. The method includes accepting a first matching circuit tuning value, measuring satellite vehicle (SV) carrier-to-noise ratio (C/N) associated with the first tuning value and a first search time interval, measuring the SV C/N associated with a next tuning value, and selecting the tuning value associated with the highest SV C/N to tune the matching circuit. In one aspect, the method further includes comparing the SV C/N to a first minimum threshold. If the first tuning value SV C/N exceeds the first minimum threshold, then the method measures the SV C/N associated with the next tuning value. Otherwise, a default tuning value can be selected to tune the matching circuit.

Abstract: A wireless communication device is provided with a multipart case, having electrical interfaces that encourage the flow of radiation frequency ground current between case sections. The multipart case has a first planar groundplane section and a second planar groundplane section. For example, the multipart case design may be a slider, double slider, multiple hinge, flip, or swivel case. The second planar groundplane is substantially coplanar with the first groundplane in a case open position, and substantially bi-planar with the first groundplane in a case closed position. The wireless device also includes an antenna located adjacent the second groundplane section first end. A first and a second interface electrically connect the first groundplane section to the second groundplane section second end (the end opposite the antenna).

Abstract: A system and method is provided for full-duplex antenna impedance matching. The method comprises: effectively resonating a first antenna at a frequency selectable first channel in a first frequency band; generating a first antenna impedance at the first channel frequency; effectively resonating a second antenna at a frequency selectable second channel in the first frequency band; generating a second antenna impedance at the second channel frequency; supplying a first conjugate impedance match at the first channel frequency; and, supplying a second conjugate impedance match at the second channel frequency. For example, the first antenna may be used for transmission, while the second antenna is used for received communications. The antennas effectively resonant in response to: supplying frequency selectable conjugate impedance matches to the antennas; generating frequency selectable antenna impedances; and/or selecting the frequency of antenna resonance.

Abstract: A dual-band antenna matching system and a method for dual-band impedance matching are provided. The method comprises: accepting a frequency-dependent impedance from an antenna; and, selectively supplying a conjugate impedance match for the antenna at either a first and a second communication band, or a third and a fourth communication band. More specifically, the method comprises: tuning a first tuning circuit to a first frequency; and, simultaneously tuning a second tuning circuit to a second frequency. In response, a conjugate match is supplied to the antenna in the first communication band in response to the first frequency. Simultaneously, the antenna is matched in the second communication band in response to the second frequency. When the first tuning circuit is tuned to a third frequency, and the second tuning circuit is tuned to a fourth frequency, then conjugate matches are supplied for the third and fourth communication bands, responsive to the third and fourth frequencies, respectively.

Abstract: A sub-band antenna matching method and an antenna matching system for selectively matching a communication bandwidth segment impedance have been provided. The method comprises: accepting a frequency-dependent impedance from an antenna; and, selectively supplying a conjugate impedance match for the antenna at a sub-band of a first communication band. In some aspects, the method selectively supplies a conjugate impedance match for the antenna at a sub-band of a second communication band. More specifically, the method comprises: tuning a first tuning circuit to a first frequency; simultaneously tuning a second tuning circuit to a second frequency to match the antenna at a low end of the first communication band. Likewise, the first tuning circuit is tuned to a third frequency and the second tuning circuit is tuned to a fourth frequency to match the antenna at a high end of the first communication band in response to the third and fourth frequencies.

Abstract: A tunable bandpass filter is provided that comprises a first shunt-connected ferroelectric (FE) tunable tank circuit having a first node to accept an input signal. A second shunt-connected FE tunable tank circuit has a second node to supply a bandpass filtered signal. A first capacitor is connected in series between the first and second nodes. In one aspect, the first tank circuit comprises a first resonator connected to the first node, and a fourth capacitor connected between the first resonator and a reference voltage. The fourth capacitor is a tunable FE capacitor. Typically, a fifth capacitor is connected between the first node and the reference voltage. Likewise, the second tank circuit comprises a second resonator connected to the second node, and a sixth (FE) capacitor connected between the second resonator and the reference voltage. A seventh capacitor is connected between the second node and the reference voltage.

Abstract: A constant-gain phase shifter is provided, comprising a first tank circuit with a first node to accept an input signal, a first inductor connected between the first node and a reference voltage, and a first capacitor connected in parallel with the first inductor. The first tank circuit modifies the phase and the insertion loss associated with the input signal. A variable gain circuit has as input connected to the first node, an input to accept a control signal, and an output to supply a gain-modified signal. A second tank circuit comprises a second node connected to the variable insertion loss circuit output to supply a constant-gain phase-shifted signal, a second inductor connected between the second node and the reference voltage, and a second capacitor connected in parallel with the second inductor. The second tank circuit modifies the phase and insertion loss associated with the gain-modified signal.

Abstract: A patch antenna includes a radiating element positioned on one side of a printed circuit board and an electromagnetic shield positioned on the opposite side of the printed circuit board. The electromagnetic shield forms at least a portion of a counterpoise and is connected to the ground of the PCB in at least one location. Design flexibility in positioning the antenna within a portable communication device is maximized while the size of the portable communication device is minimized.

Abstract: Wireless communication device antenna matching circuit tuning responsive to power control signals, and, optionally, responsive to received signal quality indicators in a traffic channel. Systems and methods are provided that increase the antenna efficiency in either the transmit frequency or the receive frequency as needed, based on fading and environmental conditions, non-ideal antenna efficiency balance, mobile station forward versus reverse link usage and system forward versus reverse link usage. The antenna efficiency may be changed incrementally or may be optimized completely for the transmit frequency or the receive frequency. The re-balancing is accomplished by tuning the antenna matching circuit. One way to tune the antenna matching circuit is to apply a voltage to a ferro-electric capacitor in the matching circuit, thereby changing the capacitance of the ferro-electric capacitor, thereby changing the impedance of the antenna system.

Abstract: Wireless communication device tuning an antenna matching circuit to favor a receive band efficiency over a transmit band efficiency in an acquisition state. Systems and methods are provided that increase the antenna efficiency in the receive band when the wireless communication device is searching for a synchronization message in order to acquire a communication channel. The antenna efficiency may be changed incrementally or may be optimized completely for the receive frequency. The increase in antenna efficiency in the receive band is accomplished by tuning the antenna matching circuit. One way to tune the antenna matching circuit is to apply a voltage to a ferro-electric capacitor in the matching circuit, thereby changing the capacitance of the ferro-electric capacitor, thereby changing the impedance of the matching circuit.

Abstract: Wireless communication device tuning an antenna matching circuit responsive to a receive signal quality indicator and, optionally, responsive to a failed access probe is provided. Systems and methods are provided that increase the antenna efficiency in either the transmit frequency or the receive frequency in an idle or access state as needed, based on fading conditions, non-ideal antenna efficiency balance, mobile station forward versus reverse link usage and system forward versus reverse link usage. The antenna efficiency may be changed incrementally or may be optimized completely for the transmit frequency or the receive frequency. The re-balancing is accomplished by tuning the antenna matching circuit. One way to tune the antenna matching circuit is to apply a voltage to a ferro-electric capacitor in the matching circuit, thereby changing the capacitance of the ferro-electric capacitor, thereby changing the impedance of the matching circuit.

Abstract: An exemplary printed monopole multi-band antenna comprises a common radiator element, a first radiator arm connected to the common radiator element and a second radiator arm connected to the common radiator element. Electromagnetic coupling between the first radiator arm and the second radiator arm contributes to and/or shifts the resonance of the first radiator arm and the second radiator arm, thereby allowing the multi-band antenna to be tuned such that the first radiator arm is capable of resonating at a first frequency range and at a second frequency range, and the second radiator arm is capable of resonating at a third frequency range.

Abstract: A mismatch detector including a directional device adapted to couple signals across the device and a detector coupled to a port on the directional device and configured to measure a reflected power a second detector coupled to a port on the directional device and configured to measure a transmit power. The mismatch detector may be used in wireless communication devices, including, but not limited to mobile wireless devices, base stations, and communication systems.

Abstract: A capacitively-loaded loop antenna and corresponding radiation method have been provided. The antenna comprises a transformer loop having a balanced feed interface and a capacitively-loaded loop radiator. In one aspect, the capacitively-loaded loop radiator is a balanced radiator. In another, the transformed loop and capacitively-loaded loop radiator are physically connected. That is, the transformer loop and the capacitively-loaded loop radiator have a portion shared by both of the loop perimeters. Alternately, the loops are physically independent of each other. In one aspect, the perimeters have a rectangular shape. Other shapes such as round or oval are also possible. In another aspect, the planes formed by the transformer and capacitively-loaded loop radiator can be coplanar or non-planar, while both loops are orthogonal to a common magnetic near-field generated by the transformed loop.

Abstract: The position sensor of the present invention includes a pair of elongated conducting members disposed in a parallel arrangement and a conducting metallic ball or mercury drop freely movable following the pair of elongated conducting members while maintaining a simultaneous contact with the pair of elongated conducting members, which combination provides two electric circuits respectively including a first circuit including a first poriton of the two elongated conducting members and the contact provided by the metallic ball or mercury drop, and a second electric circuit including the second portion of the two elongated conducting members and the same contact, wherein the metallic ball or mercury drop divides the combination of the two elongated conducting members into the first and second portions.