Abstract: A coupler circuit that includes two parallel coupled transmission lines (first transmission line and second transmission line) and a third transmission line, one end of the third transmission line connects to the end of first transmission line at one side, the other end of the third transmission line connects to the end of the second transmission line at the other side. Various coupling value and impedance transforming ratio can be achieved by select corresponding even and odd mode impedance of the coupled transmission lines and characteristic impedance of the crossing transmission line.

Abstract: An integrated circuit, comprising a single-ended pin for transmitting and/or receiving an RF signal. A first matching network is configured to match an impedance of the RF signal. A second matching network is configured to match an impedance of an on-chip differential circuit. A third matching network is configured to match an impedance of an on-chip single-ended circuit, wherein the third matching network is connectable to the first matching network. A transformer is connected or connectable to the second matching network and to the first matching network. Switches control an operating mode of the integrated circuit The second matching network is connected with the first matching network via the transformer, or the third matching network is connected with the first matching network.

Abstract: A communications network, a HVAC system employing a communications system and a method of manufacturing a component for the HVAC system are disclosed. In one embodiment, the communications network includes: (1) a dominant node having a predetermined coupling impedance and (2) a plurality of end nodes coupled to the dominant node, each of the plurality having an end node coupling impedance, wherein a total of each the end node coupling impedance and the predetermined coupling impedance is substantially a defined maximum loading impedance for the communication network.

Abstract: Coupling circuit for coupling a power line communication device to a power line network, including a first network port coupled between a network phase line and a first network line, a second network port coupled between a network neutral line and a second network line, a third network port coupled between a network ground line and a third network line, a first differential modem port including a first terminal and a second terminal, a second differential modem port including a third terminal and a fourth terminal, a first transformer including a first network side winding and a first modem side winding, a second transformer including a second network side winding and a second modem side winding, the transformers including respective terminals, a center tap extending from the midpoint of the first network side winding to a terminal of the second network side winding and a plurality of capacitors.

Abstract: An impedance matching apparatus is provided. The impedance matching apparatus includes a signal separation unit, an impedance detection unit, and an impedance matching unit. The signal separation unit separates a transmission and reception signal, and selectively passes a desired frequency corresponding to the transmission and reception signal. The impedance detection unit receives a signal outputted from the signal separation unit to detect first and second electric potentials between a plurality of impedances. The impedance matching unit compares the first and second electric potentials detected by the impedance detection unit to match the impedances.

Abstract: An antenna tuner is placed between a Power Amplifier (PA) and an antenna. The antenna tuner includes programmable components that can be tuned in order to effect an impedance translation between the antenna and the PA output. In an embodiment, the antenna tuner is adapted dynamically based on changes in the impedance of the antenna. In another embodiment, the antenna tuner is controlled based on measurement of the voltage reflection coefficient S11.

Abstract: Disclosed is an impedance matching apparatus performing impedance matching between a front-end module and an antenna. The impedance matching apparatus includes an RF front end providing a multi-band RF signal, a reflected power measuring module measuring a reflection coefficient for the RF input signal, a matching unit adjusting impedance so that the reflection coefficient is minimized, a first switch module provided in the RF front end to selectively switch the RF signal onto a bypass path, and a controller allowing the RF signal to be switched onto the bypass path if a specific frequency range is detected from the reflection coefficient.

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: Provided is an impedance stabilization device having a configuration in which a circuit including a series matching impedance element (11a and 12a (11b and 12b)) and a high-frequency blocking element connected in parallel is inserted in series into at least one of lines (10a (10b)) constituting a power line, and the lines (10a and 10b) are connected via another circuit including a parallel matching impedance element (13) and a low-frequency matching element (14) connected in series. A high-frequency signal passes through the series matching impedance element, a power current passes through the high-frequency blocking element, and the parallel matching impedance element functions as a termination resistor when a terminal on an equipment side is an open end.

Abstract: A millimeter-wave radio frequency (RF) system, and method thereof for transferring multiple signals over a single transmission line connected between modules of a millimeter-wave RF system. The system comprises a single transmission line for connecting a first part of the RF system and a second part of the RF system, the single transmission line transfers a multiplexed signal between the first part and second part, wherein the multiplexed signal includes intermediate frequency (IF) signal, a local oscillator (LO) signal, a control signal, and a power signal; the first part includes a baseband module and a chip-to-line interface module for interfacing between the baseband module and the single transmission line; and the second part includes a RF module and a line-to-chip interface module for interfacing between the RF module and the single transmission line, wherein the first part and the second part are located away from each other.

Abstract: In accordance with a representative embodiment, an impedance matching circuit for use at an output stage of a power amplifier is disclosed. The impedance matching circuit comprises: an input port for receiving a frequency band signal; and a plurality of paths, each path being allocated with a principal band signal to be transmitted therethrough and including a path on-off network and a fixed-value impedance matching network. Depending on a type of the received frequency band signal, the path on-off network is configured to activate a selected one of the plurality of paths by rendering an input impedance of the selected path to have a lower absolute magnitude so that the signal is transmitted therethrough, and to deactivate the remaining paths of the plurality of paths by rendering the input impedance thereof to have a higher absolute magnitude so that the signal is not transmitted therethrough.

Abstract: A system for transmitting an electrical signal, notably a frequency-related electrical signal, includes two conducting lines each having a central conductor surrounded by a conducting sheath, the lines being coupled and isolated from one another at each end by a transformer. The central conductor of a line is linked at the input of the system to a coil of a first transformer and at the output of the system to a coil of the second transformer. The invention is applied for example for the transmission of strongly disturbed environment measurement signals.

Abstract: A semiconductor device includes: a terminal configured to input a signal from a signal source; a receiver configured to receive the signal from the signal source through the terminal; and a terminal circuit configured to be coupled between the terminal and an input end of the receiver, and to suppress reflected wave caused by signal reflection at the receiver, wherein impedance of a wire line connecting the terminal and the input end of the receiver, and direct-current impedance of a resistance component included in the terminal circuit are set lower than impedance of an external wire line connected to the terminal.

Abstract: A microwave transmission assembly comprising a combiner comprising first and second input ports and internal and external output a ports; the combiner being adapted to transfer a signal received at microwave frequency f1 at the first input port to the external output port and signals received at other frequencies to the internal output port; the combiner being further adapted to transfer a signal at a microwave frequency f2 at the second input port to the external output port and signals received at the other frequencies to the internal output port; a resistive load connected to the internal output port; and, a power dependent reflective load connected in series with the resistive load, the power dependent reflective load comprising a reactive element, the reactive element comprising an inductive component and a capacitive component and being adapted to resonate at a load frequency; the impedance of the capacitive component being adapted to drop when the incident microwave power received by the power dependen

Abstract: Disclosed are various embodiments for tuning an antenna. Multiple phase sets for a tuning circuit impedance are generated. Each phase set includes multiple phase values. A reflected voltage corresponding to each of the phase values is determined. For each phase set, one of the phase values is selected based on the corresponding reflected voltage. The phase values for each phase set that is subsequent to an initial phase set are generated. The phase values are based on the selected phase value for the previous the phase set.

Abstract: A coupling interface couples a transceiver to one or more capacitive voltage dividers of a power transmission system. The coupling interface includes a first signal path including an adjustable inductance configured to form a resonance circuit with a capacitance associated with the one or more capacitive voltage dividers. The coupling interface may include a second signal path including an adjustable inductance configured to form a resonance circuit with the capacitance associated with the one or more capacitive voltage dividers.

Abstract: A frequency stabilization circuit includes a primary side circuit connected to a feeder circuit, and a secondary side circuit electromagnetically coupled to the primary side circuit. The primary side circuit is a series circuit including a first coiled conductor and a second coiled conductor, and the secondary side circuit is a series circuit including a third coiled conductor and a fourth coiled conductor. An antenna element is connected through a high pass filter to a first antenna connection portion set as a connection point of the first coiled conductor and the second coiled conductor. Additionally, the antenna element is connected through a low pass filter to a second antenna connection portion set as a connection point between the second coiled conductor and the fourth coiled conductor.

Abstract: A phase-shift network may include a first capacitor connected between a first input node and a first output node, and a second capacitor connected between a second input node and a second output node. Further, a 5 first filter section may be connected between the first input node and the second output node, and a second filter section may be connected between the second input node and the first output node. One or both of the first and second filter sections may include an inductance and a high-pass network. The high-pass network may include third and fourth capacitors and a first inductor. The inductance and third and fourth capacitors may be connected in series between the respective input and output nodes. The first inductor may have a first end connected to an intermediate node between the third and fourth capacitors and a second end connected to a circuit ground.

Abstract: The signal integrity of a high speed heavily loaded multidrop memory bus is often degraded due the numerous impedance mismatches. The impedance mismatches causes the bus to exhibit a nonlinear frequency response, which diminishes signal integrity and limits the bandwidth of the bus. A compensating element, such as a capacitor which ties the bus to a reference plane (e.g., a ground potential), or an inductor wired in series with the bus, is located approximately midway between the memory controller and the memory slots. The use of the compensating element equalizes signal amplitudes and minimizes phase errors of signals in an interested frequency range and diminishes the amplitudes of high frequency signals which exhibit high degrees of phase error. The resulting bus structure has increased desirable harmonic content with low phase error, thereby permitting the bus to exhibit better rise time performance and permitting a higher data transfer rate.

Abstract: A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load impedance, an energy-storing element being connected to the second terminal of the load impedance and providing an output signal, and a measuring unit that measures the output signal or compares the output signal with a reference.

Abstract: A phase-shift network may include a lattice network including a first capacitor coupling a first circuit node to a second circuit node, a second capacitor coupling a third circuit node to a fourth circuit node, and a first inductor coupling the first circuit node to the fourth circuit node. A first coupled section may couple a single-ended input node to the lattice network. A second coupled section may couple the lattice network to a single-ended output node. Each coupled section may include a plurality of conductors that may form a transmission line, such as a coaxial transmission line or a stripline. A high-pass circuit may couple the input node to the first coupled section. A phase difference network may include a signal divider producing two intermediate signals coupled to respective phase-shift networks producing output signals having substantially constant phase difference over a frequency range.

Abstract: A high-frequency signal combiner comprises at least one first bridge coupler (1; 1?; 1?) for the transformation of two input-end, first high-frequency signals (IN1, IN2, IN3, IN4) into at least two output-end, first high-frequency signals (OUT1, OUT2, OUT3, OUT4), in each case with identical power, and a second bridge coupler (3?) for the transformation of four input-end, second high-frequency signals (IN5, IN6, IN7, IN8), in each case with identical power, into an output-end, second high-frequency signal (OUT5), of which the power corresponds to the summated power of the four input-end, second high-frequency signals (IN5, IN6, IN7, IN8). In this context, the four input-end, second high-frequency signals (IN5, IN6, IN7, IN8) are each supplied from one output-end, first high-frequency signal (OUT2, OUT4, OUT1, OUT3).

Abstract: Radio frequency signals having a plurality of frequency ranges are received and coupled to a plurality of transmission lines, each of the plurality of transmission lines being formed in a corresponding plurality of generally parallel planes. Circuitry is formed for each of the plurality of transmission lines to define substantially low impedances for all of the plurality of frequency ranges except for a frequency range or ranges to be carried by the corresponding transmission line. Signals are coupled to the plurality of transmission lines so that signals with the plurality of frequency ranges are received and distributed with substantially decreased reflection and substantially high impedance matching by the plurality of transmission lines.

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: When dynamically varying a number of active paths in a system, a desired return loss is maintained. Certain embodiments enable dynamic varying of the impedance of parallel signal paths in a system responsive to the number of active ones of the parallel paths dynamically changing, in order to maintain a relatively constant impedance match between a source and the combination of parallel paths, thereby retaining a desired return loss.

Abstract: A multiband matching circuit of the present invention includes an inductive element having one end connected to an input terminal, a first switch having one end connected to the other end of the inductive element and the other end grounded, a capacitive element having one end connected to the input terminal, a second switch having one end connected to the other end of the capacitive element and the other end grounded, a first-band matching circuit that is connected between the other end of the inductive element and a first output terminal and performs impedance matching in a first frequency band, and a second-band matching circuit that is connected between the other end of the capacitive element and a second output terminal and performs impedance matching in a second frequency band higher than the first frequency band.

Abstract: A signal splitting apparatus comprises a micro-strip line, a first inductor and a second inductor. A first end and a second end of the micro-strip line are grounded via a first capacitor and a second capacitor, respectively. The first end and the second end of the micro-strip line are electrically coupled to a receiving part of a transceiver and a transmitting part of the transceiver, respectively. One end of the first inductor is coupled to the first end of the micro-strip, and the other end of the first inductor is electrically coupled to an antenna module and grounded via a third capacitor. One end of the second inductor is coupled to the second end of the micro-strip, and the other end of the second inductor is electrically coupled to the antenna module.

Abstract: The invention relates to a device for coupling individual high-frequency amplifiers (M1, M2, . . . Mn) operating at a frequency f, including n high-frequency inputs E1, E2, . . . Ei, . . . Ep, . . . En, n being an integer greater than 1, i and p being two integers between 1 and n, p being different from i, and a power high-frequency output (S) to supply a load (R) with a power which is the sum of the powers supplied by all the individual amplifiers connected via their power outputs to said high-frequency inputs. The coupling device includes n inductors L1, L2, Li, . . . Lp, . . . Ln connected by one of their ends to a respective high-frequency input, their other ends being connected together to one end (B) of an output capacitor (Cs) the other end of which is connected to the high-frequency output (S) in order to form as many series resonant LC circuits, resonating at the operating frequency f, between the inputs E1, E2, . . . Ei, . . . Ep, . . .

Abstract: A multiband matching circuit includes a first matching unit, a second matching unit, and a third matching unit, with all units being connected in series in a signal path. Matching with target impedance is established at a first frequency by appropriately designing the first matching unit and at a second frequency by appropriately designing the second and third matching units. The second matching unit and the third matching unit are designed to make the conversion ratio of the impedance viewed from the connection point between the second matching unit and the third matching unit to a circuit element to the target impedance smaller than the conversion ratio of the impedance viewed from the connection point between the first matching unit and the second matching unit to the circuit element to the target impedance, at the second frequency.

Abstract: A radio frequency (RF) signal combiner/splitter may include a printed circuit board (PCB) having first and second opposing major surfaces, and openings therethrough. The RF signal combiner/splitter may further include a ferromagnetic body. The ferromagnetic body may include a first portion spaced from the first major surface of the PCB, a second portion spaced from the second major surface of the PCB, and interconnecting portions coupling the first and second portions and extending through respective openings in the PCB. The PCB may include conductive traces cooperating with the ferromagnetic body to define circuitry for combining/splitting RF signals. For example, the PCB may further comprise additional conductive traces cooperating with the ferromagnetic body to define impedance matching circuitry coupled to the circuitry for combining/splitting RF signals.

Abstract: Disclosed herein is an asymmetric power divider. The asymmetric power divider includes a power dividing unit, a first matching network, and a second matching network. The power dividing unit supplies different amounts of power to a carrier amplifier and a peaking amplifier, which are connected in parallel. The first matching network is connected between the power dividing unit and the carrier amplifier so as to perform impedance matching between the power dividing unit and the carrier amplifier. The second matching network is connected between the power dividing unit and the peaking amplifier so as to perform impedance matching between the power dividing unit and the peaking amplifier.

Abstract: Apparatus and methods for matching the antenna of a radio device. In one embodiment, a capacitive sensor is arranged in the antenna structure and configured to detect the electric changes in the surroundings of the antenna. The mismatch caused by a change is rectified by means of the signal proportional to the sensor capacitance. This capacitance and the frequency range currently in use are input variables of a control unit. The antenna impedance is adjusted by means of a reactive matching circuit, the component values of which can be selected from a relatively wide array of alternatives by way of change-over switches, which are located in the transverse branches of the matching circuit.

Abstract: A high frequency power distribution device includes: a distribution member for uniformly dividing a high frequency power into divided high frequency powers; coaxial transmission lines through which the divided high frequency powers are introduced to the parallel plate electrodes; and an impedance control mechanism which controls an input impedance to decrease a current value. The distribution member includes: a high frequency power input unit for inputting the high frequency power to an input point; and a plurality of high frequency power output units spaced from each other at a regular interval, and each of the coaxial transmission lines are connected to one of the high frequency power output units, and the impedance control mechanism is provided at the high frequency power input unit.

Abstract: A microwave transmission assembly comprising a combiner comprising first and second input ports and internal and external output a ports; the combiner being adapted to transfer a signal received at microwave frequency f1 at the first input port to the external output port and signals received at other frequencies to the internal output port; the combiner being further adapted to transfer a signal at a microwave frequency f2 at the second input port to the external output port and signals received at the other frequencies to the internal output port; a resistive load connected to the internal output port; and, a power dependent reflective load connected in series with the resistive load, the power dependent reflective load comprising a reactive element, the reactive element comprising an inductive component and a capacitive component and being adapted to resonate at a load frequency; the impedance of the capacitive component being adapted to drop when the incident microwave power received by the power dependen

Abstract: A portable wireless device that makes it possible to maintain any desired matching state and can suppress an increase in the loss accompanying matching if the impedance characteristic of an antenna changes with expansion/storage of the antenna, deformation of a housing, etc., is provided. Two channels of signal paths that can be selected by switch section 11, 15 are provided between an antenna 10 and a reception circuit 16; a first low noise amplifier 13 that can amplify a received high frequency signal is provided in one path and a second low noise amplifier 18 having an impedance characteristic different from the low noise amplifier 13 is provided in the other signal path. The form of the antenna 10 or the form of a housing is detected in a form change detection section 20 and the two channels of signal paths are automatically switched in a control section and two types of impedance matching states are used properly.

Abstract: Methods and apparatuses for determining uplink receive signal path characteristics in a wireless communication system are disclosed. In one embodiment, a tower-top noise source (TTNS) is provided such that it is permanently affixed in close proximity to a receive antenna. The TTNS preferably has an output that includes a wideband noise signal having predetermined characteristics. The TTNS output is selectively connected to a receive signal path that includes a tower-top low-noise amplifier (TTLNA). An altered version of the wideband noise signal is received at the output of the receive signal path, and a characteristic of the altered wideband noise signal is measured.

Abstract: A phase-shift network may include a first capacitor connected between a first input node and a first output node, and a second capacitor connected between a second input node and a second output node. Further, a first filter section may be connected between the first input node and the second output node, and a second filter section may be connected between the second input node and the first output node. One or both of the first and second filter sections may include a first inductance and an high-pass network. The high-pass network may include third and fourth capacitors and a first inductor. The first inductance and third and fourth capacitors may be connected in series between the respective input and output nodes. The first inductor may have a first end connected to an intermediate node between the third and fourth capacitors and a second end connected to a circuit ground.

Abstract: A differential signal transmission device transmits N differential signal pairs from a differential signal generator to a number of receiving terminals. The N differential signal pairs include N positive signals and N negative signals. The N positive signals are clustered at a first positive clustering point. The first positive clustering point is connected to a second positive clustering point via a first matching resistor. The second positive clustering point is grounded via a first grounding resistor, and outputs a number of positive signals to the number of receiving terminals respectively. The N negative signals are clustered at a first negative clustering point. The first negative clustering point is connected to a second negative clustering point via a second matching resistor. The second negative signal clustering point is grounded via a second grounding resistor, and outputs a number of negative signals to the number of receiving terminals respectively.

Abstract: A reconfigurable antenna comprises two or more mutually coupled radiating elements and two or more impedance-matching circuits (56, 58) configured for independent tuning of the frequency band of each radiating element. In addition, each radiating element is arranged for selective operation in each of the following states: a driven state, a floating state and a ground state.

Abstract: A dual band amplifier is provided comprising a first matching circuit disposed in a first radiofrequency path between an input port and a first amplifier and a second matching circuit disposed in a second radiofrequency path between the input port and a second amplifier. The first matching circuit transforms a first input impedance of the first amplifier to a predetermined input port impedance when the radiofrequency signal is in a first frequency range and transmits the first input impedance to the input port when the radiofrequency signal is in the second frequency range. The second matching circuit transforms the second input impedance to the input port impedance when the input signal is in the second frequency range and transmits the second input impedance to the input port when the radiofrequency signal is in the first frequency range.

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: A balun signal splitter for use in transceiver systems, such as wireless communications systems, including a wide-band balun with a secondary winding for signal splitting between two operating bands (e.g., high-band and low-band) or modes. An example of a balun signal splitter configured for dual-band or dual-mode operation or includes a balun having a primary winding and a secondary winding, the secondary winding having a first port and a second port, a first network coupled to the first port and configured to present a short circuit impedance at the first port at out-of-band frequencies or during out-of-mode operation, and a second network coupled to the second port and configured to present a short circuit impedance at the second port at out-of-band frequencies or during out-of-mode operation.

Abstract: A method, structure, and design structure for a through-silicon-via Wilkinson power divider. A method includes: forming an input on a first side of a substrate; forming a first leg comprising a first through-silicon-via formed in the substrate, wherein the first leg electrically connects the input and a first output; forming a second leg comprising a second through-silicon-via formed in the substrate, wherein the second leg electrically connects the input and a second output, and forming a resistor electrically connected between the first output and the second output.

Abstract: The communication system includes a trunk line constituted of first and second signal lines for transmitting differential signals, a plurality of branch lines each branching from the trunk line and connected with a node, and at least one reflection prevention circuit connected between the first and second signal lines. The reflection prevention circuit includes a rectifier circuit configured to inhibit a current from flowing between the first and second signal lines when a voltage between the differential signals is smaller than or equal to a predetermined voltage, and allow a current to flow between the first and second signal lines when the voltage between the differential signals is larger than the predetermined voltage, and a resistive element connected in series to the rectifier circuit between the first and second signal lines.

Abstract: When a power amplifier mounted in mobile communications equipment, such as a mobile-phone, is composed of a balanced amplifier, technology with which the loss of the electric power composition in a power combiner can be reduced is provided. According to the technical idea of the present embodiment, by dividing an isolation capacitor element into two capacitor elements with high symmetry and coupled in parallel, it is possible to make almost equal parasitic capacitance arising from these capacitor elements, even when the capacitor elements are formed as interlayer capacitor elements of the wiring substrate.

Abstract: For one disclosed embodiment, an integrated circuit may comprise an internal transmission line in one or more layers of the integrated circuit. The internal transmission line may be coupled to receive a signal from an external transmission line at a first end of the internal transmission line without use of termination circuitry. The internal transmission line may transmit the signal passively to a second end of the internal transmission line. The integrated circuit may also comprise first circuitry having an input coupled to the internal transmission line at a first location of the internal transmission line to receive the signal and second circuitry having an input coupled to the internal transmission line at a second location of the internal transmission line to receive the signal. The second location may be different from the first location. Other embodiments are also disclosed.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a process for obtaining a first operational metric for a transmitter of a communication device, determining a range of impedances based on the first operational metric where the range of impedances is associated with an acceptable level of performance for the communication device, obtaining a second operational metric for the transmitter, determining a target impedance within the range of impedances based on the second operational metric, and tuning a first impedance matching network based on the target impedance, where the first impedance matching network is coupled with a first antenna of the communication device, and where the tuning is based on adjusting a first variable component of the first impedance matching network. Additional embodiments are disclosed.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a matching network for a communication device having first and second antennas, where the matching network includes a first variable component connectable and a detector. The first variable component can be connectable along a first path between the first antenna and a front end module of the communication device, where the first antenna is configured for transmit and receive operation. The detector can be connectable along a second path between the second antenna and the front end module of the communication device, where the detector obtains an RF voltage associated with the second path, where the second antenna is configured for a diversity receive operation, and where the first variable component is adjusted based on the detected RF voltage to tune the matching network. Additional embodiments are disclosed.

Abstract: A distributing apparatus distributes a high-frequency signal received from a transmitting-and-receiving module of a first wireless terminal to transmitting-and-receiving modules of other wireless terminals with a wiring scheme. The apparatus has at least three signal transmission lines each transmitting the high-frequency signal. It also has a connecting node that connects an end of each of the signal transmission lines to each other, and an attenuator on each of the signal transmission lines and positioned near the connecting node, the attenuator on each signal transmission line attenuating the high-frequency signal on that signal transmission line. An input or output terminal of each of the transmitting-and-receiving modules of the wireless terminals is connected to any one of the signal transmission lines with a wiring scheme. One of the transmitting-and-receiving modules then transmits a communication signal.

Abstract: A communication system transmits signals having frequencies that lie within a transmission band and receives signals having frequencies that lie within a reception band. The system includes a duplexer and an antenna. The duplexer includes a transmission branch and a reception branch. The transmission branch includes a transmission filter, a transmission phase shifting network and a transmission matching network. The reception branch includes a reception filter, a reception phase shifting network and a reception matching network. The transmission matching network and the reception matching network have predominately constant phase shifts over frequencies within the reception band and within the transmission band, respectively. The antenna is coupled to the transmission matching network and to the reception matching network, and shows a predominantly reactance-only impedance variation over frequencies in the transmission band and over frequencies in the reception band.