Abstract: Power consumption of near-field communication devices is regulated by waking the device for communications when a potential external near-field device is detected, and by adjusting the resonant antenna circuit to account for the detected change in antenna environment. Such near-field communication devices include a resonant loop antenna circuit. The resonant loop antenna circuit is connected to an integrated circuit that includes a controller for controlling near-field communications via the resonant loop antenna circuit, an inductance detection circuit to detect changes in the antenna inductance, a wake-on circuit responsive to a sufficient change in antenna inductance to transition the controller from a low power sleep mode to a communications mode, and an antenna tuning circuit to adjust the variable component of the resonant loop antenna circuit to compensate for changes in antenna inductance and to maintain the target range of operation.

Abstract: Exemplary embodiments are related to a dynamic gate bias for an electronic switch. A device may include a radio-frequency (RF) switch configured to receive an RF signal. The device may further include a bias generator configured to convey a bias signal based on a power level of the RF signal to the RF switch.

Abstract: A radio circuit includes a front-end module, a board, a liquid MEMS component, and a coupling component. The front-end module is implemented on at least one integrated circuit (IC) die and includes a variable circuit. The variable circuit is adjustable to facilitate an operational adjustment of the front-end module for a given operational condition of the radio circuit. The board supports the liquid MEMS component and supports, at least indirectly, the at least one IC. The coupling component electrical couples the liquid MEMS component to the variable circuit, wherein, based on a control signal, one or more characteristics of the liquid MEMS component is changed, which adjusts the variable circuit.

Abstract: A circuit for a single differential-inductor oscillator with common-mode resonance may include a tank circuit formed by coupling a first inductor with a pair of first capacitors; a cross-coupled transistor pair coupled to the tank circuit; and one or more second capacitors coupled to the tank circuit and the cross-coupled transistors. The single differential-inductor oscillator may be configured such that a common mode (CM) resonance frequency (FCM) associated with the single differential-inductor oscillator is at twice a differential resonance frequency (FD) associated with the single differential-inductor oscillator.

Abstract: An electronic device may be provided with a primary antenna that is used for transmitting and receiving signals and a secondary antenna that is used for receiving signals. The primary and secondary antennas may be used together in a diversity arrangement when receiving signals. The electronic device may have a transceiver. A phase shifter may be interposed between the transceiver and the secondary antenna. Control circuitry may select a communications band of interest for transmitting signals with the primary antenna. The control circuitry can adjust the phase shifter in real time based on which communications band of interest has been selected for transmission with the primary antenna. The phase shifter may impose a phase shift on signals carried between the secondary antenna and the transceiver that ensures that primary antenna efficiency degradation associated with the presence of the secondary antenna in the vicinity of the primary antenna is avoided.

Abstract: A SAW-less receiver includes an FEM interface module, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a mixing module, a mixed buffer section, and a frequency translated BPF (FTBPF) circuit module. The mixing module converts an inbound RF signal into an in-phase (I) mixed signal and a quadrature (Q) mixed signal. The mixed buffer section filters and buffers the I mixed signal and filter and buffer the Q mixed signal. The FTBPF circuit module frequency translates a baseband filter response to an IF filter response such that the FTBPF circuit module filters undesired signal components of the IF I signal and the IF Q signal to produce an inbound IF signal. The receiver IF to baseband section converts the inbound IF signal into one or more inbound symbol streams.

Abstract: An EHF communication system including an EHF communication chip. The EHF communication chip may include an EHF communication circuit having at least one controllable parameter-based module having a testable and controllable operating parameter The EHF communication chip may further include a test and trim circuit coupled to the EHF communication circuit, where the test and trim circuit includes a logic circuit having one or more memory elements, where the logic circuit is coupled to the controllable parameter-based module.

Abstract: Resource allocation to user terminals of a satellite system is optimized, the user terminals configured for data communication with a satellite via a common antenna beam. A resource is allocated, within the common antenna beam, to each user terminal i such that, when total available bandwidth A of the common antenna beam is not less than the total desired bandwidth ?=?i=1n ?i of the antenna beam, bi is no less than ?i, where: ?i is bandwidth demand at user terminal i, approximately equal to Ti-des/si; Ti-des is proportional to a throughput requirement by user terminal i; and si is an estimated spectral efficiency of user terminal i. When A is less than ?, bandwidth bi is allocated to each user terminal such that a number of user terminals supplied respective bandwidth not less than ?i is maximized.

Abstract: A first RF diplexer, which includes a first RF highpass with tunable notch filter and a first RF lowpass with tunable notch filter, is disclosed. The first RF diplexer has a first main port, a second main port, and a first common port. The first RF highpass with tunable notch filter is coupled between the first main port and the first common port. The first RF lowpass with tunable notch filter is coupled between the second main port and the first common port. The first RF highpass with tunable notch filter has a first highpass notch frequency, which is tunable. The first RF lowpass with tunable notch filter has a first lowpass notch frequency, which is tunable.

Abstract: A single hybrid receiver is provided for processing both single carrier and carrier aggregated (CA) communications signals where carriers are split into independent receive paths without any additional external components. The receiver receives all contiguous and non-contiguous intra-band CA and inter-band CA signals allowing for improved rejection and balanced rejection of jamming signals on either side of the two carrier signals.

Abstract: The present disclosure relates to impedance tuning of transmitting and receiving antennas.

Abstract: The various embodiments of the present disclosure relate generally to power-conscious self-healing transceiver systems and methods. An embodiment of the present invention provides a method of power-consciously self-healing a transceiver system. The method comprises providing a transceiver device having a plurality of tuning elements configured to control a plurality of specifications of the device, determining initial values for the plurality of tuning elements, and performing a hardware-iterative gradient search to obtain values for each tuning element such that the plurality of specifications are within a tolerated range.

Abstract: Methods and apparatus to mitigate radio frequency interference generated by hardware circuitry and received by wireless circuitry of a wireless communication device are described. A processor obtains a set of wireless performance metrics for signals received by the wireless circuitry. The processor determines a preferred operating mode for the hardware circuitry based on the set of wireless performance metrics and provides an indication of the preferred operating mode to the hardware circuitry. The hardware circuitry is configured for operation in accordance with the preferred operating mode. The processor and/or a second processor provide an indication to the wireless circuitry when the hardware circuitry initiates and terminates an operation that can cause radio frequency interference into the wireless circuitry. The wireless circuitry is configured during a time period that the hardware circuitry is operational to mitigate effects of radio frequency interference generated by the hardware circuitry.

Abstract: A wireless mesh network comprising a plurality of mobile mesh devices coupled as nodes in a mesh network topology is provided herein. Generally speaking, each mobile mesh device may be a portable, self-contained unit, which does not require network or power wiring to communicate network traffic between the nodes. According to one embodiment, the mobile mesh device may include a plurality of dipole antennas, which are enclosed within the mobile mesh device and configured to forward network traffic. At least one of the dipole antennas may be a frequency adjustable end-fed dipole antenna comprising a channel selection pin, which can be adjusted up or down along the dipole axis to change a resonant frequency of the dipole antenna. A method for setting or adjusting a resonant frequency of a frequency adjustable end-fed dipole antenna is also provided herein.

Abstract: According to a wireless circuit, in a case where a control section carries out switching between use frequency bands of an antenna, the control section sets, in accordance with a first set value which has been adjusted by an impedance variable matching section before the switching, a set value of an impedance variable matching section after the switching. This prevents communication, which is carried out by the wireless circuit including the variable matching section, from being cut off when the use frequency band are switched.

Abstract: The present invention provides a noncontact interface technique capable of performing communication operation without stopping an internal operation even when a clock signal cannot be extracted from a carrier wave. In a semiconductor device that receives a modulated carrier wave from an antenna, generates an internal clock signal on the basis of a clock signal extracted from the received carrier wave, and performs operation synchronously with the internal clock signal, a PLL circuit that receives the extracted clock signal and generates the internal clock signal is provided with a voltage control oscillation function. In the case where the clock signal extracted from the carrier wave is discretely interrupted, the function makes the internal clock signal maintained at a frequency immediately before the interruption. With the configuration, even when the clock signal extracted from the carrier wave is interrupted, internal data processes such as decoding and bus interfacing can be continued.

Abstract: A wireless device is described. The wireless device includes a tunable front end module. The tunable front end module includes a Tx microelectromechanical system bandpass filter. The tunable front end module also includes a first Rx microelectromechanical system bandpass filter. The wireless device also includes a power amplifier. The wireless device further includes a low noise amplifier.

Abstract: A radio-electric inhibitor device having an adjustable gain chain of radio frequency device; a frequency mixing circuit connected to the an adjustable gain chain; a second adjustable gain chain of radio frequency device; and a central control unit independently connected to each one of the adjustable gain chain of radio frequency device, the frequency mixing circuit connected to the an adjustable gain chain; and the second adjustable gain chain of radio frequency device.

Abstract: The invention provides circuitry integrated into a silicon chip that measures aspects of an RF signal on a transmission line in order to provide data that is ultimately used by an antenna tuner circuit to substantially match the impedance of the antenna with that of the transmission line providing the RF frequency to be transmitted.

Abstract: A method and communications device for providing antenna tuning to compensate for antenna de-tuning caused by a presence of an object detected using an antenna element within a capacitive touch and proximity sensor (CTPS). The CTPS propagates object detection signals associated with a detected object to a detection IC. An object detection and antenna tuning (ODAT) logic uses object detection signal information to generate tuning control signals to trigger compensatory antenna tuning, based on pre-established mappings of object detection signal data and antenna tuning states. The tuning control signals indicate at least one of (a) a level of compensatory antenna impedance tuning and (b) an amount of compensatory antenna length adjustment. In response to generating the tuning control signals, the ODAT logic triggers the propagation of the tuning control signals to the antenna matching and control circuit to provide the corresponding antenna tuning.

Abstract: An electronic device includes a main antenna and a diversity antenna. The diversity antenna includes a first portion configured to enable a transceiver to receive a signal in a first low-band frequency of four frequency bands. A second portion enables the transceiver to receive a signal in first and second high-band frequencies. A third portion is RF coupled to the first portion when the third portion is connected to ground. The third portion tunes the first portion such that the transceiver receives a signal in a second low-band frequency. A switch is connected between the third portion and the ground. When the switch is open, the first portion enables the transceiver to receive the signal in the first low-band frequency. When the switch is closed, the third portion tunes the first portion to enable the transceiver to receive the signal in the second low-band frequency.

Abstract: Technologies are generally described for an aggregation of bandwidth from multiple wireless devices. In some examples, a source device may communicate with a destination device at a first bandwidth. The source device may divide data into a first piece and a second piece. The source device may transmit the first piece to a first wireless device and the second piece to a second wireless device over a first network. The first wireless device and second wireless device may communicate with the destination device at a second bandwidth and a third bandwidth respectively. The first bandwidth may be less than an aggregation of the second bandwidth and the third bandwidth. The first wireless device may transmit the first piece over a second network, different from the first network, to the destination device. The second wireless device may transmit the second piece over a third network, different from the first network, to the destination device.

Abstract: A wireless transceiver includes at least one RF transceiver section that generates an outbound RF signal based on outbound data and that generates inbound data based on an inbound RF signal. A configuration controller configures the wireless transceiver, by configuring the wireless transceiver to identify a plurality of communication paths to a remote station, the plurality of communication paths including at least one indirect communication path through at least one intermediate station; configuring the wireless transceiver to communicate with the remote station based on a first path of the plurality of communication paths; and configuring the wireless transceiver to communicate with the remote station based on a second path of the plurality of communication paths.

Abstract: A method and system performs antenna tuning using detected changes in antenna self-capacitance in a wireless communication device. A modem detects changes in antenna self-capacitance by utilizing multiple antenna elements. The modem determines a current antenna loading condition using the detected changes in antenna self-capacitance. The modem determines appropriate tuning states for each antenna matching and tuning circuit (AMTC) associated with a respective antenna element. In order to determine the appropriate tuning states, the modem utilizes pre-established antenna self-capacitance information which is mapped to antenna tuning states. The antenna tuning states which are respectively mapped to pre-established antenna self-capacitance are empirically pre-determined by correlating antenna self-capacitance changes to antenna impedance changes.

Abstract: A tunable wideband distribution circuit for transmitting a wireless signal over a transmission line is disclosed. The tunable wideband distribution circuit may include a programmable gain buffer, wherein the gain of the programmable gain buffer is based at least in part on a frequency of the wireless signal. The tunable wideband distribution circuit may also include a tuning element configured to modify an effective impedance of the transmission line based at least on the frequency of the wireless signal, wherein the tuning element is electrically coupled to the transmission line.

Abstract: A testing system comprises a noise source coupled to at least two antenna elements. The noise source forms a total noise power on the basis of a total signal power received by the emulator, a gain of at least one antenna-specific channel between the emulator and the antenna elements, and a desired signal-to-noise ratio. The noise source transmits noise at the total noise power from the at least two antenna elements to the device under test wirelessly.

Abstract: An apparatus comprising an amplifier comprising an input, a capacitor having a capacitor first side and a capacitor second side, wherein the capacitor first side is coupled to the input, a switch having a switch first side and a switch second side, wherein the switch first side is coupled to the capacitor second side, and a transistor having a transistor gate, and a transistor source, wherein the transistor gate is coupled to the input and the capacitor first side, wherein the transistor source is coupled to the switch second side and wherein the switch is positioned directly between the capacitor second side and the transistor source.

Abstract: Embodiments of radio frequency (RF) filter front-end circuitry are disclosed that include a tunable RF filter structure having weakly coupled resonators and a Voltage Standing Wave Ratio (VSWR) control circuit. The VSWR control circuit is configured to detect a VSWR at a terminal of the tunable RF filter structure and to dynamically tune the tunable RF filter structure based on the VSWR. In this manner, the VSWR control circuit tunes the tunable RF filter structure to improve performance of tunable RF filter structure over variations in the VSWR.

Abstract: A mobile radio receiver for a vehicle. The mobile radio receiver includes a tuner front-end section, a location data port, a sensor port, and a data processing unit. The location data port is used for receiving tuner location data. The sensor port is used for receiving one or more sensor signals. The data processing unit is operably connected with the tuner front-end section, with the location data port, and with the sensor port. The data processing unit further comprises predetermined tuner location data and predetermined relationship data sets for determining a set of tuner front-end section parameters based on the sensor signals. The mobile radio receiver provides an operational mode, a checking mode, a tuner parameter adjustment mode, and a tuner parameter application mode.

Abstract: A system that incorporates teachings of the subject disclosure may include, for example, a method for detecting a plurality of use cases of a communication device, determining an initial tuning state for each of a plurality of tuning algorithms according to the plurality of use cases, configuring each of the plurality of tuning algorithms according to their respective initial tuning state, executing a first tuning algorithm of the plurality of tuning algorithms according to an order of execution of the plurality of tuning algorithms, detecting a stability condition of the first tuning algorithm, and executing a second tuning algorithm of the plurality of tuning algorithms responsive to the detected stability condition of the first tuning algorithm. Each tuning algorithms can control one of a tunable reactive element, a control interface, or both of one of a plurality of circuit components of a radio frequency circuit. Other embodiments are disclosed.

Abstract: A circuit for a single differential-inductor oscillator with common-mode resonance may include a tank circuit formed by coupling a first inductor with a pair of first capacitors; a cross-coupled transistor pair coupled to the tank circuit; and one or more second capacitors coupled to the tank circuit and the cross-coupled transistors. The single differential-inductor oscillator may be configured such that a common mode (CM) resonance frequency (FCM) associated with the single differential-inductor oscillator is at twice a differential resonance frequency (FD) associated with the single differential-inductor oscillator.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a matching network including a tunable reactance circuit configured to be coupled to at least one of a transmitter portion and a receiver portion of a communication device, wherein the tunable reactance circuit is adjustable to a plurality of tuning states, and wherein the determination of a tuning state is based on parameters associated with a detected interference. Additional embodiments are disclosed.

Abstract: According to one embodiment, an antenna apparatus comprises an antenna element connected to a feeding point, a grounded first lumped constant element connected to the antenna element, and a grounded second and third lumped constant elements connected to the antenna element through a selector. The selector is configured to connect the grounded second lumped constant element to the antenna element in order to lower a resonant frequency of the antenna element, and to connect the grounded third lumped constant element to the antenna element in order to raise the resonant frequency of the antenna element.

Abstract: A group of transistors operate as a combined power amplifier, to amplify signals to be transmitted, and as a low noise amplifier, to amplify signals which are received. In a first mode, the group of transistors is configured to amplify the signals to be transmitted by turning all of the transistors in both a first subset and a second subset on. In a second mode, the group of transistors is configured to amplify the signals which have been received by turning on the first subset of transistors and turning off the second subset of transistors.

Abstract: A cellular phone including a transceiver and a processing module. The transceiver receives, from a device separate from the cellular phone, a radio or intermediate frequency signal. The radio frequency signal has been tuned by the device to a selected frequency. The intermediate frequency signal is a downconverted version of the radio frequency signal. Each of the radio and intermediate frequency signals includes the content. The content has been frequency modulated and broadcast at the selected frequency prior to the transceiver receiving the radio or intermediate frequency signal. A processing module downconverts the radio or intermediate frequency signal to a baseband signal and converts the baseband signal to a digital signal. The processing module either forwards the digital signal for audio play out of the content at the cellular phone or forwards the digital signal to the transceiver for transmission of the digital signal back to the device.

Abstract: An information handling system includes a capacitor, an antenna, a wireless wide area network card, an embedded display port interface, and a digital-to-analog converter. The capacitor has a variable capacitance that varies based on a voltage applied to the capacitor. The antenna is coupled to the capacitor, and has a variable resonance frequency that is based on the variable capacitance. The wireless wide area network card is in communication with the antenna, and is configured to set the variable resonance frequency to a specific frequency based on a control signal. The embedded display port interface is configured to transmit the control signal from the wireless wide area network card to a display control circuit via an auxiliary channel of the embedded display port interface. The digital-to-analog converter is in communication with the display control circuit, and is configured to provide the voltage to the capacitor in response to a signal from the display control circuit.

Abstract: A system that incorporates teachings of the present disclosure can include, for example, an apparatus having a matching network adapted to reduce a magnitude of a signal reflection at a port of the matching network. The matching network can have one or more controllable variable reactive elements. A controller can be adapted to determine reflection coefficient information from incident and reflected waves sampled at the port of the matching network, and follow at least one cycle of a coarse tune process for generating one or more control signals to tune one or more reactances of the one or more controllable variable reactive elements. Additional embodiments are disclosed.

Abstract: A mobile terminal for automatically adjusting antenna matching, and a control method thereof, are provided. By determining whether an RSSI value is less than a preset value, a mobile terminal, and a control method thereof, may send an SPI control signal according to a judgment result, and an SPI control interface may transmits the SPI control signal to an antenna matching module to control a magnitude of variable capacitance and variable inductance. Thereby antenna matching impedance may be adjusted to increase an RSSI value. A mobile terminal, and a control method thereof, may include a good communication signal and high call quality.

Abstract: Several multiband transceivers are disclosed. An exemplified multiband transceiver supporting different bands has a transformer, an inbound switch circuit, and an outbound switch circuit. The transformer has input ports on a primary side, and output ports on a secondary side. The input ports are direct-current isolated from and magnetically coupled to the output ports. The inbound switch circuit is configured to connect one of the input ports with an RF signal source for signal transmission. The outbound switch circuit is configured to connect one of the output ports with a RF output load. Optionally, an input tunable capacitor is configured to shunt with the effective inductance of one of the input ports and form a LC tank for band selection.

Abstract: Several multiband transceivers are disclosed. An exemplified multiband transceiver supporting different bands has a transformer, an inbound switch circuit, and an outbound switch circuit. The transformer has input ports on a primary side, and output ports on a secondary side. The input ports are direct-current isolated from and magnetically coupled to the output ports. The inbound switch circuit is configured to connect one of the input ports with an RF signal source for signal transmission. The outbound switch circuit is configured to connect one of the output ports with a RF output load. Optionally, an input tunable capacitor is configured to shunt with the effective inductance of one of the input ports and form a LC tank for band selection.

Abstract: A method (600) and devices for enhancing the performance of one or more antennas (440) is provided. A control circuit (104) assesses performance of an antenna (101) in a plurality of bands, such as a receive band and a transmit band. The control circuit (104) then selects one of the bands, e.g., a lesser performing band, as a “selected band” for which the antenna (101) will be optimized. The control circuit (104) can then adjust an adjustable impedance matching circuit (103) coupled to the antenna (101) to improve the efficiency of the antenna (101) in the selected band and can adjust a resonance of the antenna (101) to further improve an efficiency of the antenna (101) in the selected band.

Abstract: A spectrum analyzer is configured to display, on a display, reception signal intensity of each of multiple frequencies. A smoothing unit is configured to smooth signal intensity data of each of the multiple frequencies to produce smoothed data. A peak frequency detection unit is configured to detect, as a peak frequency, a frequency at a position indicating a maximum value in the smoothed data closest to a contact position that a touch sensor detects. A reception frequency determination unit is configured to determine a reception frequency of a radio wave that a receiver for a voice call receives based on the peak frequency.

Abstract: Systems and methods for tuning an antenna for a frequency modulation (FM) transceiver are provided. A representative system includes: a network of electrical adjustable passive components that receives and sends radio frequency (RF) signals to a receiver circuitry via the network of electrical adjustable passive components. The receiver circuitry determines the received signal strength indication (RSSI) of the RF signal. The system further includes a transmitter circuitry that transmits RF signals via the network of electrical adjustable passive components, and a peak detector circuitry that receives and determines a voltage output of the RF signals from the variable capacitors. An auto-tune circuitry receives the RSSI and output value from the receiver circuitry and the peak detector circuitry, respectively.

Abstract: A system and method for connecting an external RF connector on an electrical module housing to a PCB within an electronic module is presented. The electronic module is configured to operate within a Department of Defense Joint Tactical Radio System in altitudes up to 15000 feet, at operating temperatures between ?40 to +55 degrees Celsius, in driving rain and dust storms, in a corrosive salt-sea atmosphere and to withstand indirect shock. The electronic module comprises a module housing, a housing connector on an external wall of the housing, a PCB within the housing, a PCB connector for a coaxial cable mounted on the PCB and a coaxial cable with first and second ends that is looped 360 degrees between the housing connector and the PCB connector. The first end of the cable is connected to the housing connector and the second end is connected to the PCB connector.

Abstract: Techniques for supporting multi-frequency range signal processing for a wireless device. In an aspect, a first antenna is provided to support first and third frequency ranges. A second antenna is separately provided to support two separate ranges that are each intermediate in frequency between the first and third frequency ranges. In an aspect, the two separate ranges may correspond to, e.g., a GPS range and a 1500-MHz band. To separate the two ranges of the second antenna, one or more low-pass and/or band-pass filters may be provided. In other aspects, a third antenna may be added to support a fourth frequency range higher than the third frequency range. Other frequency range combinations, dual antenna aspects, and carrier aggregation features are further disclosed herein.

Abstract: An electronic device includes a main antenna and a diversity antenna. The diversity antenna includes a first portion configured to enable a transceiver to receive a signal in a first low-band frequency of four frequency bands. A second portion enables the transceiver to receive a signal in first and second high-band frequencies. A third portion is RF coupled to the first portion when the third portion is connected to ground. The third portion tunes the first portion such that the transceiver receives a signal in a second low-band frequency. A switch is connected between the third portion and the ground. When the switch is open, the first portion enables the transceiver to receive the signal in the first low-band frequency. When the switch is closed, the third portion tunes the first portion to enable the transceiver to receive the signal in the second low-band frequency.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a matching network including a tunable reactance circuit configured to be coupled to at least one of a transmitter portion and a receiver portion of a communication device, where the tunable reactance circuit is adjustable to a plurality of tuning states, and where the determination of a tuning state is based on whether detected signal measurements are determined to be invalid and is based on information from at least one of an open-loop or closed-loop feedback configuration of the tunable reactance circuit. Additional embodiments are disclosed.

Abstract: An electronic device may include antenna structures. Wireless transmitter circuitry such as cellular telephone transmitter circuitry and wireless local area network circuitry may transmit signals using the antenna structures. A wireless receiver may receive signals from the antenna structures through an adjustable-linearity amplifier. The wireless receiver may operate in a receive band such as a satellite navigation system receive band. During operation of the electronic device, control circuitry in the device may analyze the frequencies and powers of the transmitted signals to determine whether there is a potential for interference for the receive band to be generated in the adjustable-linearity amplifier. In response to determining that there is a potential for interference, the control circuitry may increase the linearity of the adjustable-linearity amplifier.

Abstract: Apparatus and methods are disclosed related to tuning a resonant frequency of an LC circuit. In some implementations, the LC circuit can be embodied in a low noise amplifier (LNA) of a receiver. The receiver can include a component configured to generate an indicator of received signal strength indication (RSSI) of a radio frequency (RF) signal received by the receiver. A control block can adjust the resonant frequency of the LC circuit based at least in part on the indicator of RSSI. As another example, the receiver can include an oscillator, such as a VCO, separate from the LC circuit that can be used to tune the resonant frequency of the LC circuit. These apparatus can compensate for variation in a zero imaginary component of an impedance across the LC circuit.

Abstract: Disclosed is a multiband antenna apparatus. According to one embodiment of the present invention, a multiband antenna apparatus includes: an antenna radiator connected to each of a feeder pad and a ground pad on a non-ground surface of a mainboard of a wireless communication device and including a first radiator for transmitting and receiving a first frequency band and a second radiator for transmitting and receiving a second frequency band; a frequency adjusting element formed on the non-grounded surface and interconnecting the ground pad and the ground of the mainboard; and a switch unit that is formed on the non-ground surface and electrically disconnects or opens the ground pad and the ground of the mainboard in accordance with an input switching control signal. The resonant frequency of the antenna radiator shifts by the switching operation of the switching unit.