Abstract: A directional coupler is configured so as to include: a resistive element in which one end thereof is connected to a first terminal and the other end is connected to a second terminal; a first amplifier circuit for outputting either a current directly proportional to a first voltage applied to the one end of the resistive element or a current directly proportional to a second voltage applied to the other end of the resistive element; a second amplifier circuit for outputting a first current which is directly proportional to the voltage difference between the first voltage applied to the one end of the resistive element and the second voltage applied to the other end of the resistive element and whose polarity is different from that of the current outputted from the first amplifier circuit when a signal is flowing from the first terminal to the second terminal, and for outputting a second current which is directly proportional to the voltage difference between the first voltage and the second voltage and whose

Abstract: The disclosure relates to a signal combiner for a Doherty power amplifier architecture, the signal combiner including a termination circuit on an isolation port, the termination circuit being tuned to improve performance of the Doherty power amplifier. The architecture includes a carrier amplifier and a peaking amplifier. The peaking amplifier modulates the load seen by the carrier amplifier, allowing the carrier amplifier to remain in high-efficiency, saturated operation even at back-off. This load modulation can be achieved using impedance matching networks having an impedance matched to a specific frequency. The architectures include tuned or tailored signal combiners with termination circuits on isolation ports. The termination circuits are tuned or tailored for particular operating frequencies to enhance operation.

Abstract: A multiple-path amplifier (e.g., a Doherty amplifier) includes first and second transistors (e.g., main and peaking transistors) with first and second output terminals, respectively, all of which is integrally-formed with a semiconductor die. A signal path through the second transistor extends in a direction from a control terminal of the second transistor to the second output terminal, where the second output terminal corresponds to or is closely electrically coupled to a combining node. The amplifier also includes an integrated phase delay circuit that is configured to apply an overall phase delay (e.g., 90 degrees) to a signal carried between the first and second output terminals. The integrated phase delay circuit includes delay circuit wirebonds coupled between the first and second output terminals, and the delay circuit wirebonds extend in a third direction that is angularly offset from (e.g., perpendicular to) the second direction.

Abstract: An electronic package houses one or more RF amplifier circuits. At least one of an input or output impedance matching network integrated on the package and electrically coupled to the gate or drain bias voltage connection, respectively, of an amplifier circuit, includes a multi-stage decoupling network. Each multi-stage decoupling network includes two or more decoupling stages. Each decoupling stage of the multi-stage decoupling network includes a resistance, inductance, and capacitance, and is configured to reduce impedance seen by the amplifier circuit at a different frequency below an operating band of the amplifier circuit. Bias voltage connections to the impedance matching circuits may be shared, and may be connected anywhere along the multi-stage decoupling network.

Abstract: An optical circuit device includes a first to fourth optical couplers, wherein the first optical coupler splits a first input light into a first output beam and a second output beam with a 90-degree phase difference therebetween, and the second optical coupler splits a second input light into a third output beam and a fourth output beam with a 180-degree phase difference therebetween. The third optical coupler combines one of the first and second output beams and one of the third and fourth output beams, and outputs a first optical signal and a second optical signal having a 180-degree phase shift from each other. The fourth optical coupler combines the other of the first and second output beams and the other of the third and fourth output beams, and outputs a third optical signal and a fourth optical signal having a 180-degree phase shift from each other.

Abstract: A distributed antenna system (DAS) includes a master unit; a plurality of remote units communicatively coupled with the master unit and distributed to provide coverage within a service area, each of the remote units remotely located from the master unit and other remote units; a coupler element coupled to receive a plurality of MIMO signals, the MIMO signals including first and second MIMO signals, the coupler element configured to: introduce a phase shift in a first portion of the first MIMO signal to generate a first phase shifted portion of the first MIMO signal; combine the first phase shifted portion with a second portion of the second MIMO signal to generate a combined MIMO signal; and present the combined MIMO signal at a first output port of the coupler element; at least one antenna coupled with each remote unit and configured to receive the combined MIMO signal for transmission.

Abstract: An N-way RF power amplifier device includes a power divider, multiple first power amplifier circuits, multiple second power amplifier circuits, and a power combiner. The power divider divides an RF input signal into multiple differential signal pairs each including complementary first and second division signals. The first power amplifier circuits amplify the first division signals and the second power amplifier circuits amplify the second division signals in such a way that the amplified first division signals and the amplified second division signals have the same phase. The power combiner combines the amplified first and second division signals into an RF output signal.

Abstract: A gallium nitride (GaN) power amplifier having a plurality of amplifier stages integrated into a monolithic integrated circuit is disclosed. The plurality of amplifier stages is coupled together between a radio frequency signal input and a radio frequency signal output, wherein at least one of the plurality of amplifier stages includes a first GaN transistor that is configured to have a first breakdown voltage that is no more than 75% of a second breakdown voltage of a second GaN transistor included in a different one of the plurality of amplifier stages.

Abstract: According to one embodiment, an electronic circuit includes a first current path, a second current path, and a third current path. The first current path includes a first Josephson junction. The second current path includes a second Josephson junction. The third current path includes a plurality of third Josephson junctions. One end of the second current path is electrically connected to one end of the first current path. Another end of the second current path is electrically connected to another end of the first current path. One end of the third current path is electrically connected to the one end of the first current path and the one end of the second current path. Another end of the third current path is electrically connected to the other end of the first current path and the other end of the second current path.

Abstract: A coupling structure for crossing three transmission lines millimeter-wave or centimeter-wave signals a signal conductor layer of a circuit substrate, the coupling structure comprising three planar cross-couplers, and from each of the three cross-couplers two input/output points of the cross-coupler being connected clockwise in succession in the plane of the cross-coupler, to respectively one input/output point of a respective other of the three cross-couplers.

Abstract: A distributed amplification device with p inputs, p outputs, p amplification paths comprises a redundant reservoir of n amplifiers including n-p back-up amplifiers, an input redundancy ring and an output redundancy ring formed by rotary switches, the input and output redundancy rings sharing the same technology. The internal amplification pathways associated with the n-p back-up amplifiers frame in an interlaced manner the internal amplification pathways associated with the p nominal amplifiers and the amplification paths of the routing configurations each pass through at least five rotary switches. The input and output redundancy rings are topologically and geometrically configured and the family of the routing configurations is chosen such that the electrical lengths of all the paths of one and the same routing configuration of the family are equal.

Abstract: Digital content can be broadcast in a sideband of an analog broadcast channel using multiple digital in-band on-channel (IBOC) transceivers connected in a mesh configuration to form an IBOC mesh network. The digital IBOC transceivers are positioned at various geographic locations, so that unlike traditional “HD” radio broadcasts, the IBOC broadcast transmission is spread out over a wide area, using multiple low power digital IBOC transceivers rather than being broadcast from the same location as the analog signal. An edge transceiver can limit IBOC transmission power of the IBOC transceivers to a desired portion of the power used to broadcast the analog signal. The edge server can make this determination based on measurements taken at the geographically distributed digital IBOC transceivers. The IBOC mesh network provides bi-directional communication between a mesh transceiver and a user device, and can be used to deliver user feedback.

Abstract: Digital content can be broadcast in a sideband of an analog broadcast channel using multiple digital in-band on-channel (IBOC) transceivers connected in a mesh configuration to form an IBOC mesh network. The digital IBOC transceivers are positioned at various geographic locations, so that unlike traditional “HD” radio broadcasts, the IBOC broadcast transmission is spread out over a wide area, using multiple low power digital IBOC transceivers rather than being broadcast from the same location as the analog signal. An edge transceiver associated with the mesh network can deliver different broadcast content to different transceivers, or nodes, within the mesh network, by delivering content to an intermediate node and relying on the intermediate node to propagate the content through the mesh network. The mesh network provides bi-directional communication between a mesh transceiver and a user device.

Abstract: A communication device includes a power amplifier that generates power signals according to one or more operating bands of communication data, with the amplitude being driven and generated in output stages of the power amplifier. The final stage can include an output passive network that suppresses an amplitude modulation-to-phase modulation (AM-PM) distortion. During a back-off power mode a bias of a capacitive unit of the output power network component can be adjusted to minimize an overall capacitance variation. The output passive network can further generate a flat-phase response between dual resonances of operation.

Abstract: Apparatus and methods for wireless local area network (WLAN) power amplifiers are provided. In certain configurations, a WLAN power amplifier system includes a WLAN power amplifier, an output impedance matching network, and an envelope tracker. The WLAN power amplifier includes an input that receives a WLAN signal having a fundamental frequency and an output that generates an amplified WLAN signal for transmission over an antenna. The output impedance matching network is electrically connected to the output of the WLAN power amplifier, and can provide a load line impedance between 10? and 35? at the fundamental frequency. The envelope tracker receives an envelope of the WLAN signal, and controls a voltage level of a power supply of the WLAN power amplifier based on the envelope signal.

Abstract: A distributed antenna system includes a multiple-input and multiple-output (MIMO) base station configured to output at least a first signal and a second signal. At least one master unit communicates with the MIMO base station. At least one remote unit communicates with the master unit. At least one antenna is coupled with the remote unit for receiving signals from the remote unit. A coupler element is configured for introducing a phase shift in a portion of at least the first MIMO signal and for combining the phase shifted first MIMO signal portion with a portion of the second MIMO signal and presenting the combined first and second MIMO signal portions at an output port of the coupler element. An antenna is configured for receiving the combined MIMO signal portions for transmission.

Abstract: Digital content can be broadcast in a sideband of an analog broadcast channel using multiple digital in-band on-channel (IBOC) transceivers connected in a mesh configuration to form an IBOC mesh network. The digital IBOC transceivers are positioned at various geographic locations, so that unlike traditional “HD” radio broadcasts, the IBOC broadcast transmission is spread out over a wide area, using multiple low power digital IBOC transceivers rather than being broadcast from the same location as the analog signal. IBOC transmission power can be limited to a desired portion of the power used to broadcast the analog signal, based on measurements taken at the geographically distributed digital IBOC transceivers. The IBOC mesh network provides bi-directional communication between a mesh transceiver and a user device, and delivers user feedback received at one mesh transceiver to a feedback server by moving the user feedback through the IBOC mesh network.

Abstract: A matching network and method for matching a source impedance to a load impedance is provided. A bias feed microstrip structure is coupled to a direct current (DC) voltage source and has a bias feed microstrip electrical length less than one fifth of a fundamental wavelength of a fundamental frequency component of an input signal. A harmonic impedance transformation network can be configured to compensate for parasitic reactances of a precursor element. A tuned impedance element presents a short circuit impedance at the second harmonic impedance transformation network terminal for harmonic frequency components and presents a higher impedance for the fundamental frequency component. A fundamental impedance transformation network is configured to match a fundamental impedance transformation network input impedance for the fundamental frequency component to a load impedance of a load. Multiple instances of the harmonic impedance transformation network and the tuned impedance element can be provided.

Abstract: A distributed antenna system includes a multiple-input and multiple-output (MIMO) base station configured to output at least a first signal and a second signal. At least one master unit communicates with the MIMO base station. At least one remote unit communicates with the master unit. At least one antenna is coupled with the remote unit for receiving signals from the remote unit. A hybrid coupler is coupled between the remote unit and antenna and is configured to receive the first signal Ch1 and the second signal Ch2 from the remote unit on respective first and second ports and to provide an output signal on at least one output port. The output signal includes at least a portion of the first signal and at least a portion of the second signal. The antenna is coupled with the output port.

Abstract: A feed network includes three radio frequency (RF) devices constructed in a suspended-substrate stripline configuration that provides a five-port microwave device having a sum port and four feed ports. The three RF devices include at least one coupled-line quadrature hybrid and at least one Marchand balun. Each of the at least one coupled-line quadrature hybrid has only a single transmission line section providing two outputs with approximately equal amplitude power and a phase difference of 90°. Each of the at least one Marchand balun includes two offset-coupled transmission line sections separated by a gap and two outputs on opposite sides of the gap. The two outputs have approximately equal amplitude power and a phase difference of 180°. The three RF devices are electrically arranged relative to the sum port and the four feed ports such that the feed ports have equal amplitude power and a progressive 90° phase shift.

Abstract: A power amplifying apparatus includes a filter that filters a predetermined frequency, a branch line provided subsequently to the filter on a substrate on which the filter is provided to distribute power, a power amplifying device provided subsequently to the branch line to amplify power, and a connecting line provided subsequently to the power amplifying device to compose power. The power amplifying apparatus may further include a directional coupler that monitors transmitted high-frequency signals.

Abstract: Certain embodiments provide a power amplifying device including: a distribution line which distributes power; a plurality of power amplifying elements; a connection line; an output line; a filter; a first directional coupler; and a second directional coupler. The power amplifying elements is provided at a stage subsequent to the distribution line. The connection line is provided at a stage subsequent to each of the power amplifying elements and combines outputs of the power amplifying elements. The output line is connected to the connection line. The filter is placed on the connection line or the output line. The first and second directional couplers are provided at a stage subsequent to the filter. The first directional coupler outputs the high frequency signal transmitted to the output line, to a RF monitor terminal. The second directional coupler outputs the high frequency signal transmitted to the output line, to a level detection detector.

Abstract: An amplification unit is provided. The amplification unit, comprises a first amplifier, a second amplifier, a first sensor, a first predistortion component, and a signal combiner. The first amplifier amplifies a first signal to produce a second signal. The first sensor produces a third signal based on the second signal. The second amplifier turns on and to amplifies a fourth signal to produce a fifth signal when the amplitude of the fourth signal exceeds a threshold amplitude and turns off when the amplitude of the fourth signal is less than the threshold amplitude. The first predistortion component produces the first signal based on a first input signal, based on the third signal, and based on an on-off state of the second amplifier. The signal combiner produces an output of the amplification unit based on the second signal and the fifth signal.

Abstract: Combination circuitry includes a relatively small preamplifier and includes hybrid circuitry. The hybrid circuitry is configured to perform mode switching while also performing some amplification, thus allowing the relatively small preamplifier to be smaller than a conventional power amplifier. In one embodiment, the hybrid circuitry includes first series portion configured to amplify when ON, a first shunt portion, a second series portion configured to amplify when ON, and a second shunt portion. The first series portion may include: a first transistor; a first variable impedance in communication with a gate of the first transistor, wherein the first variable impedance is configured to receive a first transistor control signal; a second transistor in series with the first transistor; and a second variable impedance in communication with a gate of the second transistor, wherein second variable impedance is configured to receive a second transistor control signal.

Abstract: A power amplifier includes a power amplifier core including a plurality of gain stages to receive a radio frequency (RF) signal and to output an amplified RF signal, an output network coupled to the power amplifier core to receive the amplified RF signal and output a transmit output power signal, and a directional coupler coupled to the output network to obtain a coupled signal proportional to the transmit output power signal. Each of these components can be configured on a single semiconductor die, in an embodiment.

Abstract: A distribution amplifier with intellectual signaling comprises a first connector, a first amplifier, a second connector, a power regulator, an inductive coil, a voltage detecting circuit, a first indicating lamp, a second amplifier and a second indicating lamp. The distribution amplifier with intellectual signaling may effectively display whether the distribution amplifier operates normally or not according to the above-mentioned arrangement.

Abstract: Disclosed is a signal splitting apparatus useable in a power amplifier having two or more power amplifiers. The apparatus includes a direct gain component; and a derived gain component connected to the direct gain component. The derived gain component derives the derived gain by imposing a constraint which is valid over the entire dynamic range of the input signal, e.g. the sum of the power of the direct split signal and the derived split signal are constrained to be substantially equal to the power of the input signal. The use of combining additional direct gain and derived gain components, as well as a delay element, are disclosed so as to enable n-component splitting that for adaptation to different applications by the use of suitable coefficients.

Abstract: A power amplifier includes a first matching circuit configured to perform harmonic processing of an input signal, and a second matching circuit configured to perform the harmonic processing of an output signal, the output signal being generated by amplifying a power of the input signal. The power amplifier rotates a phase of output impedance at a matching point of the harmonic included in the generated output signal when the power of the input signal is decreased from a value higher than a certain value to a value lower than the certain value.

Abstract: An output network for use with a multi-transistor amplifier circuit comprises N transistors configured to provide a Chireix outphasing behavior. The N transistors coupled to receive different amplitude and/or phase signals relative to a source signal. The output network comprises: a plurality of branches arranged in a hierarchical structure between N input nodes and an output node; at least one branch connection arranged between the input nodes and the output node, wherein each branch connection is arranged to couple first and second branches from an input side to a single branch on an output side. The hierarchical structure is arranged asymmetrically such that at least one branch connection comprises a different number of input nodes ultimately connected to its first branch compared to the number of input nodes ultimately connected to its second branch.

Abstract: A generator of a high-power modulated signal, a method for calibrating the generator, and a magnetic resonance imaging system. The generator includes means for generating a sinewave signal phase-shifted by a first variable value relative to a phase reference and a sinewave signal phase-shifted by a given fixed value added to a second variable value relative to the phase reference, the second variable value opposite to the first variable value relative to the phase reference, the variable values representative of the modulation of the radiofrequency signal, the two sinewave signals being of constant amplitude, two amplifiers each amplifying one of the sinewave signals in a congested regime, and a fixed phase shifter with a value equal to the given value of the means to generate the two sinewave signals, the fixed phase shifter coupling the signals originating from the two amplifiers to deliver the modulated radiofrequency signal.

Abstract: Disclosed is a matrix distributed amplifier (DA) having an input transmission line, an intermediate transmission line, and an output transmission line. A first plurality of amplifiers has inputs coupled to and spaced along the input transmission line and has outputs coupled to and spaced along the intermediate transmission line. A second plurality of amplifiers has inputs coupled to and spaced along the intermediate transmission line and has outputs coupled to and spaced along the output transmission line. A termination amplifier has an input coupled to the input transmission line and an output coupled to the intermediate transmission line. In at least one embodiment, a second termination amplifier has an input coupled to the intermediate transmission line and an output coupled to the output transmission line.

Abstract: An apparatus and an operating method of an asymmetric Doherty power amplifier. A Doherty power amplifier apparatus includes a power divider configured to provide a power signal to a carrier amplifier and a peaking amplifier. The apparatus also includes the carrier amplifier configured to amplify a power of the signal input from the power divider. The apparatus further includes the peaking amplifier configured to have a maximum output power magnitude different from the carrier amplifier and amplify the power of the signal input from the power divider. The apparatus still further includes at least two offset transmission lines disposed at ends of the carrier amplifier and the peaking amplifier and configured to regulate a load impedance. The apparatus also includes an output combiner configured to combine and output outputs of the carrier amplifier and the peaking amplifier of different sizes.

Abstract: A high-frequency module including a power amplifying circuit includes a high-frequency power amplifying element, a matching circuit, and a driving power-supply circuit. The high-frequency power amplifying element includes a high-frequency amplifying circuit and a directional coupler. A first end of a main line of the directional coupler is connected to an output terminal of a latter-stage amplifying circuit of the high-frequency amplifying circuit. A second end of the main line of the directional coupler is connected through an output matching circuit to a high-frequency signal output terminal of the high-frequency power amplifying element. The output terminal of the latter-stage amplifying circuit is also connected to a second driving power-supply voltage application terminal of the high-frequency power amplifying element. The second driving power-supply voltage application terminal is connected to the high-frequency signal output terminal by a connecting conductor.

Abstract: A system including a power amplifier and a pre-distortion module coupled to the power amplifier. The pre-distortion module includes one or more smaller versions of the power amplifier to generate a pre-distortion signal that compensates for any memory-effect or inertia present in the power amplifier with application on frequency hopping and larger (up to 1 octave) instantaneous bandwidth communication systems.

Abstract: A traveling wave amplifier (TWA) primarily for driving a semiconductor optical device is disclosed. The TWA of an embodiment provides a plurality of differential amplifiers of the first type and an additional differential amplifier of the second type, where are they are connected between the input and the output of the TWA. The differential amplifiers of the first type provide a first delay from the input to the output, while, the differential amplifier of the second type provide a second delay longer than the first delay between the input and the output of the TWA.

Abstract: A circuit for amplifying an input signal can comprise a plurality of couplers. A splitting coupler of the plurality of couplers can receive the input signal and a combining coupler of the plurality of couplers can provides an output signal. N number of amplifiers can be included in the circuit to amplify the input signal, wherein N is a non-binary integer greater than one. At least one of the plurality of couplers can comprise a hybrid coupler that has two ports terminated into substantially equal reactances.

Abstract: A distribution amplifier with intellectual signaling comprises a first connector, a first amplifier, a second connector, a power regulator, an inductive coil, a voltage detecting circuit, a first indicating lamp, a second amplifier and a second indicating lamp. The distribution amplifier with intellectual signaling may effectively display whether the distribution amplifier operates normally or not according to the above-mentioned arrangement.

Abstract: Disclosed is a signal splitting apparatus useable in a power amplifier having two or more power amplifiers. The apparatus includes a direct gain component; and a derived gain component connected to the direct gain component. The derived gain component derives the derived gain from the direct gain by imposing a constraint which is valid over the entire dynamic range of the input signal, e.g. the sum of the power of the direct split signal and the derived split signal are constrained to be substantially equal to the power of the input signal. The use of combining additional direct gain and derived gain components, as well as a delay element, are disclosed so as to enable n-component splitting that for adaptation to different applications by the use of suitable coefficients.

Abstract: An amplifying device includes a signal separating unit that separates a first signal and a second signal from an input signal; a first signal-generating unit that generates, based on the first signal, a first cancelling signal that suppresses ringing caused during processing of the first signal; a first combining unit that combines the first signal and the first cancelling signal; a first amplifying unit that amplifies a signal output from the first combining unit; a second signal-generating unit that generates, based on the second signal, a second cancelling signal that suppresses ringing caused during processing of the second signal; a second combining unit that combines the second signal and the second cancelling signal; a second amplifying unit that amplifies a signal output from the second combining unit; and a third combining unit that combines a signal output from the first amplifying unit and one output from the second amplifying unit.

Abstract: A circuit for amplifying an input signal can comprise a plurality of couplers. A splitting coupler of the plurality of couplers can receive the input signal and a combining coupler of the plurality of couplers can provides an output signal. N number of amplifiers can be included in the circuit to amplify the input signal, wherein N is a non-binary integer greater than one. At least one of the plurality of couplers can comprise a hybrid coupler that has two ports terminated into substantially equal reactances.

Abstract: A system for amplifying an input signal can comprise a main amplifier to amplify a delayed version of the input signal. The system can also comprise a peak amplifier to amplify the input signal upon the input signal reaching a threshold level and disable amplification upon the input signal falling below the threshold level. The system can further comprise a voltage combiner to electromagnetically couple the output of the main amplifier and the peak amplifier, such that an output impedance at an output node of the voltage combiner is a high impedance if the input signal is below the threshold level.

Abstract: In a Doherty amplifier (100), the amplifier's input is connected to a main device (102) via a first branch and to a peak device via a second branch. The first branch has a first frequency-dependent input impedance with a first real part and a first imaginary part. The second branch has a second frequency-dependent input impedance with a second real part and a second imaginary part. The first and second imaginary parts have opposite polarity. The first and 5 second imaginary parts have a same magnitude so as to compensate each other in the frequency band. The first imaginary part and the second imaginary part implement a first phase shift in the. first branch and a second phase shift in the second branch, respectively. The first and second phase shifts each have a magnitude of substantially 45 degrees substantially in the middle of the frequency band and are of opposite polarity.

Abstract: The invention relates to a final stage three-way power combining amplifying circuit applied to power amplifier of a mobile communications base station system. The circuit includes at least a first power divider, a power combiner, a Doherty amplifier and a Class AB amplifier, as well as some transmission lines and phase-shift lines. A first output port of the first power divider is connected to a first input port of the power combiner via a first phase-shift line and the Doherty amplifier by concatenating them with transmission lines. A second output port of the first power divider is connected to an input terminal of a Class AB amplifier via a transmission line, an output terminal of the Class AB amplifier is connected to a second input port of the power combiner via a microstrip line, and the output terminal of the power combiner outputs an amplified radio frequency signal. The invention can meet the requirements of both high efficiency and low cost.

Abstract: A traveling wave amplifier (TWA) primarily for driving a semiconductor optical device is disclosed. The TWA of an embodiment provides a plurality of differential amplifiers of the first type and an additional differential amplifier of the second type, where are they are connected between the input and the output of the TWA. The differential amplifiers of the first type provide a first delay from the input to the output, while, the differential amplifier of the second type provide a second delay longer than the first delay between the input and the output of the TWA.

Abstract: According to an embodiment, a class-AB power amplifier includes an amplifying element whose power supply voltage is expressed as Vdc and whose maximum current is expressed as Imax, a conduction angle ?o of the amplifying element being more than ?(rad) and less than 2·?r(rad), and load impedance of a fundamental wave being expressed as Z1=R1+j·X1 and load impedance of a 2nd harmonic being expressed as Z2=R2+j·X2 which are observed from a dependent current source of an equivalent circuit of the amplifying element, wherein a relationship between variables X1 and R1 is set to ?R1<=X1<=R1, variable R1 is set to R1=Vdc/Imax·?·{1?cos(?o/2)}/{?o/2?sin(?o)/2}, and variable X2/X1 is set to X2/X1=?{?o/2?sin(?o)/2}/{sin(?o/2)?sin(1.5·?o)/3}, or each of the variables is set thereto so as to become equal substantially.

Abstract: The present invention relates to an amplifier circuit where a load modulation is applied to a segmented amplifier. This will reduce the shunt loss since the loss of a segmented amplifier is reduced by allowing each amplifier segment or combination of segments to operate to their full output power capacity, rather than limited to a lower output power which results in a higher shunt loss. Hence, operation to full capacity before adding more segments is made possible by dynamically modulating the load.

Abstract: In a representative embodiment, a multiple mode power amplifier that is operable in a first power mode and a second power mode. The multiple mode power amplifier comprises a first amplifying unit; a second amplifying unit; a first impedance matching network connected to an output port of the first amplifying unit; a second impedance matching network connected to an output port of the second amplifying unit and to the first impedance matching network; and a third impedance matching network connected to the output ports of the first and the second amplifying units. The third impedance matching network reduces a phase difference between signals amplified by the first and the second amplifying units in the first mode.

Abstract: An apparatus and method for maximizing the performance of a peaking amplifier in a Doherty amplifier are provided. The apparatus includes a splitter, a carrier amplifier, an (N?1) number of peaking amplifiers, a Doherty combiner, and an output load. The splitter splits an input signal into an ‘N’ number of power signals. The carrier amplifier amplifies the signal provided from the splitter using a first Direct Current (DC) bias. The peaking amplifiers amplify the signals provided from the splitter using a second DC bias, which is lower than the first DC bias. When the carrier amplifier and the peaking amplifiers are all operating, the Doherty combiner forms a load impedance of the respective amplifiers such that the load impedance of the peaking amplifiers are less than the load impedance of the carrier amplifier. The output load outputs the signals amplified by the carrier amplifier and the peaking amplifiers.

Abstract: System and method for compensating for changes in an output impedance of a power amplifier uses an impedance compensating circuit with an impedance inverter coupled to the power amplifier. The impedance inverter of the impedance compensating circuit is configured such that an output impedance of the impedance inverter is proportional to the inverse of the output impedance of the power amplifier to compensate for changes in the output impedance of the power amplifier.

Abstract: Distributed band reject filters are disclosed. A first radio frequency band reject filter is disclosed having a splitter having a first input port, a first output port and a second output port, the splitter being operable on an input signal applied to the first input port to provide a respective output signal proportional to the input signal at each of the first and second output ports, the output signals having a phase shift between 45 degrees and 135 degree with respect to the input signal, as well as first, second and third acoustic resonators coupled respectively to the first input port, the first output port and the second output port.