Abstract: A communication apparatus including a first antenna and performing wireless communication in which a reflected power from the first antenna changes depending on a positional relationship between the first antenna of the communication apparatus and a second antenna of a communication partner. The communication apparatus further includes a transmission unit configured to transmit a data signal to the communication partner via the first antenna, a determination unit configured to determine a reflected power generated when the transmission unit supplies the data signal to the first antenna, and a control unit configured to control the transmission of the data signal by the transmission unit, based on the reflected power determined by the determination unit.

Abstract: A compact antenna includes a main antenna patch. A first feed point and a second feed point connect with the main antenna patch to provide current in the main antenna. Excitation of the first feed point produces polarization in a first direction along the main antenna patch and excitation of the second feed point produces polarization in a second direction different from the first direction.

Abstract: A radio-frequency (RF) processing device, for a wireless communication device, is disclosed. The RF processing device comprises an antenna, an RF-signal processing module, a controller, for generating a control signal according to a band switching signal, and a matching adjustment module for adjusting an impedance between the antenna and the RF-signal processing module according to the control signal.

Abstract: Methods and systems for an integrated voltage controlled oscillator (VCO)-based transmitter and on-chip power distribution network are disclosed and may include supplying bias voltages and/or ground to a chip utilizing conductive lines. One or more VCOs and low-noise amplifiers (LNAs) may each be coupled to a leaky wave antenna (LWA) integrated in the bias voltage and/or ground lines. One or more clock signals may be generated utilizing the VCOs, which may be transmitted from the LWAs coupled to the VCOs, to the LWAs coupled to the LNAs. RF signals may be transmitted via the LWAs, and may include 60 GHz signals. The LWAs may include microstrip and/or coplanar waveguides, where a cavity length of the LWAs may be dependent on a spacing between conductive lines in the waveguides. The LWAs may be dynamically configured to transmit the clock signals at a desired angle from a surface of the chip.

Abstract: A computing device with a configurable antenna. The antenna is configured through a switching circuit operating under software control. Operating characteristics of the antenna are configured based on connections between conducting segments established by the switching circuit, allowing the nominal frequency, bandwidth or other characteristics of the antenna to be configured. Because the switching is software controlled, the configurable antenna may be integrated with a software defined radio. The radio and antenna can be reconfigured to support communication according to different wireless technologies at different times or to interleave packets according to different wireless technologies to support concurrent sessions using different wireless technologies.

Abstract: A frequency synthesizer includes a controlled oscillator configured to extend a temperature range and phase noise of the synthesizer without compromising the frequency coverage of the synthesizer. The frequency synthesizer also includes bias generation circuitry that sets a bias current of a charge pump to reduce bandwidth variations of the synthesizer. The frequency synthesizer further includes switching circuitry to dynamically turn a charge pump on and off to reduce effects of current leakage in the charge pump.

Abstract: The invention utilizes small, narrow-band and frequency adaptable antennas to provide coverage to a wide range of wireless modes and frequency bands on a host wireless device. The antennas have narrow pass-band characteristics, require minimal space on the host device, and allow for smaller form factor. The frequency tunability further allows for a fewer number of antennas to be used. The operation of the antennas may also be adaptably relocated from unused modes to in-use modes to maximize performance. These features of the antennas result in cost and size reductions. In another aspect, the antennas may be broadband antennas.

Abstract: An embodiment of the present invention provides an apparatus, comprising a transceiver, an antenna tuner connecting said transceiver to an antenna, a power sensor adapted to acquire measurements about transmit power, a receive signal strength indicator (RSSI) adapted to acquire measurements about receive power and wherein said tuner tunes said antenna based upon said transmit and receive measurements to optimize said antenna in both the receive and transmit bands.

Abstract: An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

Abstract: A contactless communication medium includes a base made of an insulating material, an antenna coil section including a conductor wound in a planar shape on the base, an inductance adjusting conductor pattern that is connected in parallel to a part of the conductor in the antenna coil section, and is placed on the base, a capacitor connected to the antenna coil section, and a communication processing section that is connected to the antenna coil section and the capacitor to perform contactless communication processing.

Abstract: A system including a diversity module and an antenna selection module. The diversity module is configured to measure (i) a first signal-to-noise ratio and a first error rate associated with a first antenna, and (ii) a second signal-to-noise ratio and a second error rate associated with a second antenna. The antenna selection module is configured to select the first antenna or the second antenna by comparing (i) the first signal-to-noise ratio to the second signal-to-noise ratio, and (ii) the first error rate to the second error rate.

Abstract: An adjustment module, an electronic device with the adjustment module, and an antenna performance adjusting method thereof are disclosed. The adjustment module is used for adjusting an antenna module. The antenna module is disposed in the electronic device and used for radiating a wireless signal. The adjustment module includes a monitoring module, a determining module, and a capacitance adjusting unit. The monitoring module is used for detecting an alternating current signal waveform when the antenna module radiates the wireless signal. The determining module receives the alternating current signal waveform and is used for generating an adjusting voltage value when the alternating current signal waveform is a non-constant amplitude. The capacitance adjusting unit is used for changing a capacitance value according to the adjusting voltage value to adjust a resonance point coordinate of the antenna module.

Abstract: A circuit arrangement includes a component having a closed signal path, that closed signal path connected to a first port, a second port and at least a third port. The component has a directed signal flow of a signal applied to one of that ports. Such a coupling device can be connected to a transmitter and to a receiver path, respectively.

Abstract: Apparatus and method for reducing the current consumption and increasing the efficiency of an RF power amplifier (PA), according to which the load, connected to the output stage of the PA, tuned dynamically or statically for each level of the desired output power. By doing so, the output impedance of the output stage is essentially matched, such that the dynamic RF load line has a slope that corresponds to the impedance required to provide this level. Whenever a smaller output power is desired in response to reduction in the input signal to the amplifier, the load is further tuned, such that the dynamic or static RF load line has a slope that causes the power amplifier to essentially remain in saturation at the smaller output power.

Abstract: An apparatus and method manage impedance values in a radio in a wireless network. The apparatus includes a tunable matching network (TMN) positioned on a path between a transceiver and an antenna. The TMN includes a plurality of immittance elements. A voltage standing wave ratio (VSWR) detector is configured to detect a ratio of a signal passing the VSWR detector and a signal reflected from the TMN. A control circuit is configured to identify an operating setting for the radio, set a number of the immittance elements based on the operating setting, monitor the ratio detected by the VSWR detector, and modify a setting of at least one of the immittance elements based on the ratio detected.

Abstract: A method, transceiver integrated circuit (IC), and communications device for generating antenna tuning states derived from a pre-established trajectory of tuning states to adjust a detected signal level towards a preset, given value. A tuning state generation (TSG) controller determines whether a detected signal level matches a given value. If the detected signal level does not match the given value, the TSG controller selects an initial preset tuning state from a pre-established trajectory corresponding to a pre-identified operating condition that best matches a current operating condition. The TSG logic forwards the initial preset tuning state to the antenna tuner to trigger impedance transformation. Following generation of the initial preset tuning state, the controller receives an updated detected signal level. If the updated detected signal level fails to match the given value, the controller generates an incremental tuning state that is interpolated between the initial and a final preset tuning states.

Abstract: The present invention relates to a layout for antenna loops having both functions of capacitance induction and electromagnetic induction, and particularly relates to the layout for antenna loops having both functions of capacitance induction and electromagnetic induction, wherein the capacitance detection elements are integrated with the antenna loops. In this layout for antenna loops, each of the antenna loops therein is separated into three sections, and there are several geometric structures fabricated in two of these sections. These geometric structures are capacitance detection elements. Therefore, the two sections are directly fabricated to be the capacitance detection elements because of these geometric structures. By this way, the antenna loops can be integrated with the capacitance detection elements and the capacitance detection elements do not prevent the antenna loops from receiving the electromagnetic signals.

Abstract: A MIMO receiving apparatus that can demodulate a spatially multiplexed signal without using any division operation requiring a large quantity of operation resources. In the MIMO receiving apparatus, stream separation section (105) separates a spatially multiplexed signal into a plurality of streams based on numerator submatrix A. Numerator submatrix A is determined according to channel matrix H and a canceller scheme and corresponds to a numerator of stream separation matrix S that equalizes the phase and amplitude of the spatially multiplexed signal. Denominator part calculation section (108) calculates a denominator (denominator coefficient) of stream separation matrix S and correction section (117) corrects a threshold determined according to a modulation scheme of the spatially multiplexed signal using the denominator (denominator coefficient) of stream separation matrix S.

Abstract: A low loss quarter wave Radio Frequency (RF) relay switch apparatus and method provides more efficient transmission of RF energy to downstream antenna switching elements in an antenna switching network. The antenna switching network may include multiple antenna multiplexer modules which are configured to operate in a local use configuration or a pass through configuration. The antenna multiplexer modules are designed for maximum efficiency in the pass through configuration acting virtually lossless when passing through RF energy.

Abstract: Diversity arrays of antenna elements and phased arrays of antenna elements can be used to produce omni-directional transmissions. Communication signaling is produced based on a desired communication signal that is to be transmitted omni-directionally. In response to the communication signaling, the antenna elements cooperate to effect approximately omni-directional antenna transmission of the desired communication signal.

Abstract: In a high frequency antenna switch module, an I/O interface generates various control signals for controlling a switch module on the basis of a system data signal and a system clock, a decoder generates a switch control signal SWCNT for controlling a switch in response to a control signal CNT in the control signals, a timing detector for switch-ports switching generates a switch-port switching detection signal t_sw in response to the switch control signal, a frequency control signal generator generates frequency control signals ICONT and CCONT in response to the signal t_sw, and a negative voltage generation circuit generates a negative voltage output signal NVG_OUT while switching the frequency of the clock signal generated in the negative voltage generation circuit to different frequencies in response to signals ICONT and CCONT. The switch switches the paths among the plural switch ports in response to the signals SWCNT and NVG_OUT.

Abstract: Methods and systems for a voltage-controlled oscillator (VCO) with a leaky wave antenna are disclosed and may include transmitting wireless signals via one or more leaky wave antennas in one or more tank circuits coupled to one or more VCOs. The VCOs may be two-point modulated. Two modulating signals may be communicated to the one or more VCOs via varactors coupled to tank circuits on the one or more VCOs. The varactors may include CMOS transistors with source and drain terminals shorted together. The one or more leaky wave antennas may be integrated on the chip, on a package to which the chip is affixed, or on a printed circuit board to which the chip is affixed. The VCOs may be integrated in a phase-locked loop and an output of the one or more VCOs in the phase-locked loop may be fed back via a multi-modulus detector.

Abstract: An antenna with a built-in filter for use in an electronic device includes: an antenna element; and a circuit board unit connected to the antenna element, wherein the circuit board unit includes: a filter circuit that filters input and output signals of the antenna element; and a matching circuit that performs impedance matching of the antenna element.

Abstract: A computer-implemented method for optimizing communication performance based on antenna polarization, comprising transmitting a data stream to a client device using at least one antenna structure having one or more antenna polarization, determining a need to adjust antenna polarization, selecting an antenna from the at least one antenna structure, determining an antenna polarization adjustment based on a level of communication performance of the at least one antenna structure, and dynamically making the antenna polarization adjustment for the data stream being transmitted using the selected antenna.

Abstract: An apparatus and a method of realizing an antenna matching in accordance with a user's body effect and a state of a mobile device are provided. The method includes determining a state of the mobile device on a basis of a call mode and at least one of whether an external device is connected to the mobile device, whether a receiver is being used, whether a speaker is being used, and whether a proximity sensor is activated, determining an optimal Tunable Matching Network (TMN) circuit adjustment value in accordance with the determined state, and performing the antenna matching in accordance with the optimal TMN circuit adjustment value.

Abstract: An antenna system for reception of channel signals form the UHF band by a receiver, including an electrically small antenna and, connected between the port connected to the antenna and that of the receiver, an active impedance matching device controlled by command signals depending on the quality of the signal received by the receiver to compensate for the impedance variations due to the environment associated with the antenna and to reject the frequencies of interfering channels adjacent to the reception channel without interfering with the active impedance matching of the antenna.

Abstract: Disclosed are an antenna tuner and a method for adjusting antenna impedance. The antenna tuner includes a reference impedance resistor, a first coupler having an isolated port connected to one end of the reference impedance resistor, a second coupler having an input port connected to an output port of the first coupler and an output port connected to the antenna, and an impedance adjusting device group connected to the second coupler to adjust impedance of the antenna. An impedance controller generates an impedance adjustment control signal according to a first voltage applied to a coupled port of the first coupler, and a second voltage applied to a coupled port of the second coupler to provide the impedance adjustment control signal to the impedance adjusting device group.

Abstract: An embodiment of the present invention provides a method for limiting tuning of a matching network having variable reactive elements coupled to a variable load impedance to at least reduce an undesirable effect caused by an RF signal. Other embodiments are disclosed.

Abstract: Provided are apparatuses and methods for transmitting and receiving ESG fragments associated with an event or program. The event or program may have an interaction service component in which a subscriber can interact with the program in real-time. The program content information, such as audio and video data associated with the program may be transmitted to a subscriber in an ESG fragment. The ESG fragment may have associated metadata in which information pertaining to the interaction service component of the event or program may be mapped. The subscriber terminal or receiver can parse the ESG fragment data to determine attributes for displaying a message template associated with the interaction service component of the event or program. Subscriber interaction with the program can be provided through the message template.

Abstract: In a mobile phone, a vibrator, arranged on a substrate, has two power supply terminals. The vibrator's first and second terminals are each connected to a control unit via a first wiring, a coil and a second wiring. A capacitor is connected between the two terminals' first wirings One end of an antenna sub-element is connected to the first terminal's first wiring and one end is connected to a radio circuit unit. An antenna unit operates at frequency ?2, corresponding to a communication frequency. The control unit and the vibrator operate at frequency ?1. The coils have a self-resonant frequency of ?2 and form a short-circuit connection at frequency ?1 and an open-circuit connection at frequency ?2. The capacitors form an open-circuit connection at frequency ?1 and a short-circuit connection at frequency ?2. This reduces the number of antenna component members mounted on a radio and an antenna's size.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a tuning system for a communication device having an antenna, where the tuning system includes at least one first tunable element connected with at least one radiating element of the antenna for tuning the antenna where the adjusting of the at least one first tunable element is based on at least one of a use case associated with the communication device and location information associated with the communication device, and a matching network having at least one second tunable element coupled at a feed point of the antenna, wherein the matching network receives control signals for adjusting the at least one second tunable element to tune the matching network. Additional embodiments are disclosed.

Abstract: An antenna apparatus for backscattering an incoming radio frequency (RF) signal includes an antenna for backscattering the incoming RF signal in accordance with a reflection coefficient characteristic of the antenna. A variable impedance circuit includes an output electrically connected to the antenna. A low pass delta sigma modulator is coupled to the variable impedance circuit and digitally controls the output of the variable impedance circuit, such that the reflection coefficient of the antenna is adjusted based on the output of the variable impedance circuit.

Abstract: A radio communications device includes a headphone assembly, which includes at least one aural speaker or transducer and a headphone cable functioning as an antenna and providing electrical signals carrying audio information to the at least one aural speaker or transducer. A signal separator coupled to the headphone cable separates the electrical signals carrying audio information transmitted to the headphone cable and radio frequency (RF) signals received from the headphone cable. A radio receiver receives the RF signals from the signal separator and converts the RF signals to electrical signals carrying audio information. A tuner is provided for tuning the headphone cable to a selected operating frequency of the radio receiver. An audio amplifier amplifies electrical signals carrying audio information from the radio receiver to be transmitted through the headphone cable to the at least one aural speaker or transducer.

Abstract: Methods and systems for dynamic range detection and positioning utilizing leaky wave antennas (LWAs) are disclosed and may include configuring one or more LWAs to enable communication of signals in a particular direction. RF signals that are reflected from an object may be received via the LWAs, and a location of the object may be determined based on the received reflected RF signals. The velocity of the object may be determined based on a Doppler shift associated with the received reflected RF signals. A frequency chirped signal may be transmitted by the LWAs to determine a location of the object. A resonant frequency of the LWAs may be configured utilizing micro-electro-mechanical systems (MEMS) deflection. LWAs may be situated along a plurality of axes in the wireless device. The LWAs may include microstrip or coplanar waveguides, where a cavity height is dependent on spacing between conductive lines in the waveguides.

Abstract: A signal receiving method for receiving a signal within a predetermined bandwidth for a broadcasting system using an embedded antenna is provided, comprising: obtaining an antenna bandwidth of the embedded antenna; dividing the predetermined bandwidth into a plurality of subbands according to the antenna bandwidth; receiving a control signal; selecting one of the subbands according to the control signal; and receiving the signal using a match unit corresponding to the selected subband for matching the embedded antenna.

Abstract: Exemplary embodiments are directed to wireless power transfer. A wireless power transmitter includes a transmit antenna configured as a resonant tank including a loop inductor and an antenna capacitance. The transmitter further includes an amplifier configured to drive the transmit antenna and a matching circuit operably coupled between the transmit antenna and the amplifier. The transmitter also includes a capacitor integrating the antenna capacitance and a matching circuit capacitance.

Abstract: A signal processing circuit is disclosed, comprising a first node for coupling with a first antenna, a second node for coupling with a second antenna, a third node for receiving a first signal from a transmitting circuit, a fourth node for coupling with a receiving circuit, a signal dividing circuit, a phase shifting circuit, and a signal combining circuit. The signal dividing circuit divides the first signal into a second signal and a third signal, and transmits the second signal to the first antenna. The phase shifting circuit shifts the phase of the third signal to generate a fourth signal for canceling at least part of a coupled signal between the third node and the fourth node. The signal combining circuit combines the fourth signal and a fifth signal received from the second antenna, and transmits the combined signal to the receiving circuit.

Abstract: The communication device includes: a first body; a second body; a connecting portion that connects the first body and the second body, so as to be capable of switching between a closed state in which the first body and the second body are superimposed with each other, and an opened state in which a degree of mutual superimposition is smaller than that of the closed state; a first conductive portion that is disposed in the first body; a second conductive portion that is disposed in the second body; a signal line that electrically connects the first conductive portion and the second conductive portion via the inside of the connecting portion; a first antenna, which is disposed in at least one of the first body and the second body, and which is electrically connected to the first conductive portion or the second conductive portion; and a second antenna, which is disposed in at least one of the first body and the second body, and which is capacitively coupled with the first conductive portion or the second conduc

Abstract: A system for providing independent polarization control in a radio communication system comprises a set of common antennas and a plurality of transmitters for supplying signals to said set of common antennas Said set of common antennas is used for transmitting signals supplied by the transmitters. Said set of common antennas is used to provide elliptical polarization transmission of said signals. The system furthermore comprises a combiner for each combination of a first transmitter of said plurality of transmitters and an antenna of said not of common antennas, and an adjusting element allowing for controlling the polarization of the signal provided by said first transmitter.

Abstract: A mobile wireless device enables effective use of space in a case while reducing degradation of antenna gain and maintaining communication quality even if a plurality of antennas having different frequency bands are arranged close to one another. A magnetic antenna has a first switch unit, a second switch unit, and a concentrated constant circuit which are added to a wiring pattern at the side near to a main antenna, so that a first path and a second path can be selected. Under a predetermined condition, a CPU controls the first switch and the second switch to electrically connect terminal (A1) to terminal (B1) and electrically connect terminal (A2) to terminal (B2), thereby forming the first path; and electrically connect terminal (A1) to terminal (C1) and electrically connect terminal (A2) to terminal (C2), thereby forming the second path connected via the concentrated constant circuit.

Abstract: In various embodiments, systems and methods for automatically tuning an antenna to a desired frequency utilize a tuning detection element that sends or receives a signal in accordance with one mode of the antenna and that is separated from the antenna by a gap and outside of a signal path of the antenna. In various system implementations, a processor communicates with the tuning detection element and antenna and monitors the amplitude of a signal transmitted to or from the tuning detection element. A resonant frequency of the antenna may be tuned to the desired frequency by a tuning element.

Abstract: An antenna and power amplifier element assembly may include an antenna assembly and a quasi-optic power amplifier. The quasi-optic power amplifier may include an output transistor coupled to the antenna assembly. A harmonic trap may be coupled to the quasi-optic power amplifier.

Abstract: An antenna arrangement comprising an input/output connection and a first and a second tuning network with different transfer functions. The arrangement additionally comprises an antenna and a switch for connecting the input/output connection of the arrangement to one of said tuning networks, with a second switch for connecting the antenna of the arrangement to the tuning network to which the input/output connection of the arrangement has been connected. The arrangement comprises a sensor for sensing a form factor of the arrangement or of an apparatus in which the arrangement is used, and said sensor can be used for influencing said first and second switches, so that a device which has been connected to the arrangement may be connected to the antenna via a tuning network optimal for the current form factor of the arrangement.

Abstract: An embodiment of the present invention provides an apparatus, comprising a transceiver, an antenna tuner connecting said transceiver to an antenna, a power sensor adapted to acquire measurements about transmit power, a receive signal strength indicator (RSSI) adapted to acquire measurements about receive power and wherein said tuner tunes said antenna based upon said transmit and receive measurements to optimize said antenna in both the receive and transmit bands.

Abstract: Some embodiments of the present disclosure relate to techniques for automatically measuring antenna mismatching conditions for a given mobile phone with a given antenna in a given environment and on a given frequency. In particular, some embodiments use a two way directional coupler coupled between a radio frequency (RF) transmitter output (e.g., analog front end) and an antenna tuner. This two-way directional coupler is coupled to a mismatch calculator, which is often implemented as a software algorithm, to accurately tune an antenna tuner to limit impedance mismatch. Consequently, changes in impedance mismatch can be tracked and compensated for so the user will not experience degradations in signal quality, thereby helping reduce the number of dropped calls, for example. Also, because power is tracked and radiated more accurately, these techniques save battery energy relative to conventional solutions and can stay on-line longer with optimum transmitting conditions.

Abstract: Methods and systems for an integrated voltage controlled oscillator (VCO)-based transmitter and on-chip power distribution network are disclosed and may include supplying bias voltages and/or ground to a chip utilizing conductive lines. One or more VCOs and low-noise amplifiers (LNAs) may each be coupled to a leaky wave antenna (LWA) integrated in the bias voltage and/or ground lines. One or more clock signals may be generated utilizing the VCOs, which may be transmitted from the LWAs coupled to the VCOs, to the LWAs coupled to the LNAs. RF signals may be transmitted via the LWAs, and may include 60 GHz signals. The LWAs may include microstrip and/or coplanar waveguides, where a cavity length of the LWAs may be dependent on a spacing between conductive lines in the waveguides. The LWAs may be dynamically configured to transmit the clock signals at a desired angle from a surface of the chip.

Abstract: An impedance tuning and optimization technique is described wherein an impedance interface is dynamically tuned prior to applying transmit power to the circuit. A coupled signal injected into the antenna port is used to optimize the tuning state of a tuning component such that the impedance properties of the circuit are optimized prior to application of transmit power. A coupled or injected signal at an alternate frequency band can be utilized to determine tuning state or parameters at the frequency of interest by first tuning at the frequency of the coupled or injected signal and then accessing a data base containing information that relates tuning parameters across multiple frequency bands for various levels of antenna de-tuning. A time-savings is realized when the tuning circuit is optimized prior to activation or use of the transmit/receive path.

Abstract: Methods and systems for amplitude modulation using a leaky wave antenna are disclosed and may include amplitude modulating an output of one or more power amplifiers in a wireless device by modulating a bias current in the power amplifiers that are coupled to one or more leaky wave antennas. The leaky wave antennas may include a balun that may be integrated on the chip, on a package to which the chip may be affixed, and/or integrated on a printed circuit board to which the chip may be affixed. An output power of the power amplifiers may be adjusted by configuring a bias voltage on the leaky wave antennas. The bias voltage may be configured utilizing a DC to DC voltage controller. The bias current may be modulated via one or more switched current sources. The switched current sources may be binary weighted and/or may be current mirrors.

Abstract: A radio transmitter includes a radio module, a battery from which power is fed to the radio module, and a metal plate. The radio module includes a transmission module generating a transmission signal and an antenna configured to wirelessly transmit the transmission signal. The metal plate is located so as to cover a part of the battery and a part of the antenna. The battery is electromagnetically coupled to the antenna. A main radiation direction of the antenna is parallel to a principal surface of the metal plate.

Abstract: A method and apparatus for providing close proximity antenna measurement and tuning, includes a first receive-only antenna, a second antenna operable in a transmit mode, a tuning circuit coupled to the first antenna, a transmitter coupled to the second antenna, a receiver coupled to the first antenna, the receiver operable to measure a power into the first antenna delivered by a signal from the second antenna driven by the transmitter, and a processor coupled to the tuning circuit, transmitter, and receiver, the processor operable to step changes in the tuning circuit until a substantially maximum power of the signal is measured by the receiver.