Abstract: An integrated circuit two-stage power amplifier provides a high-voltage, series-biased FET amplifier for high-efficiency applications. An input is connected to an input matching network, and a driver cell provides power from the input matching network to an interstage power dividing network. Multiple similar cells in a second stage are connected between the interstage power dividing network and an output matching and combining network and are biased by a series-connected active biasing network. An output is connected to the output matching and combining network. One series-connected active biasing network includes series-connected resistances and a second string of series-connected buffer cells connected between the series-connected resistances and the RF power cells for biasing the RF cells.TABLE 1 ______________________________________ State-of-the-Art, Ka-band MMIC Results Freq. Power Gain PAE BW Chip (GHz) (W) (dB) (%) (GHz) #Stg. Voltage ______________________________________ 33 0.66 16.2 41.1 2.

Abstract: An integrated circuit comprising a balanced differential amplifier. The balanced differential amplifier has a first single-ended differential amplifier coupled at a first negative differential input terminal to a first input signal through a feedback network also coupled to an output terminal of the first amplifier. The first amplifier is also coupled at a first positive differential input terminal to a second input signal through a first resistor and to a reference voltage. The balanced differential amplifier also has a second single-ended differential amplifier coupled at a second negative differential input terminal to the second input signal through a second feedback network also coupled to an output terminal of the second amplifier. The second amplifier is also coupled at a second positive differential input terminal to the first input signal through a second resistor and to the reference voltage.

Abstract: A digitally-controlled variable-gain amplifier is disclosed, which comprises a polarization means to transform the input signal into differential signals of positive and negative polarity; first and second gain blocks, each composed of dual-multiplying digital-to-analog converters, which multiply the polarized signals to produce positive and negative amplified signals; and a differential amplification means which receives the amplified signals, and subtracts them from each other. The resulting output signal is proportional to the input signal and yields a 3 dB improvement in signal-to-noise ratio over a single multiplying digital-to-analog converter stage. A plurality of amplification chains, each comprising a first and second gain block, may be used to amplify the differential signals for summing by the differential amplification means to provide a greater signal-to-noise ratio improvement.

Abstract: A radio frequency signal (FIG. 2, 205) is sampled and the sample is conveyed to a video detector (220). The detected envelope amplitude is sent to an envelope tracking circuit (280), a comparator (230), and an envelope tracking and gate biasing circuit (240). Based on the instantaneous value of the envelope amplitude, the comparator (230) selects one of the available supply voltages (340) via switch drivers (270). The selected one of the available supply voltages (340) is adjusted by the envelope tracking circuit (280) and the resulting voltage output (282) is supplied to the drains of the power amplifiers (390), thus enabling operation near saturation. As the instantaneous value of the envelope amplitude increases, the comparator (230) selects higher supply voltages (340) which increases the voltage conveyed to the power amplifiers (390), thereby increasing their power output.

Abstract: An amplifier circuit having a high linearity mode of operation and a high efficiency mode of operation. The amplifier circuit comprises an amplifier having a variable active device periphery and a variable supply voltage; and a control circuit, coupled to the amplifier, for decreasing the variable active device periphery and increasing the variable supply voltage when in the high linearity mode of operation, and for increasing the variable active device periphery and decreasing the variable supply voltage when in the high efficiency mode of operation.

Abstract: Two amplifiers that are driven using outphasing modulation are coupled to one another so that the amplifiers affect each other's effective load line. The two amplifiers can maintain efficiency over a wider dynamic range than in a conventional amplifier. Amplifiers according to the invention amplify an AC input signal of varying amplitude and varying phase using a DC power supply. A converter converts the AC input signal into a first signal having constant amplitude and a first phase angle and into a second signal having constant amplitude and a second phase angle. The first amplifier amplifies the first signal, and the second amplifier amplifies the second signal. A coupler couples the first and second amplifiers to one another and to a load impedance, such that voltages or currents in the first amplifier become linearly related to voltages or currents in the second amplifier.

Abstract: A low noise amplifier circuit provides high gain and an input impedance matching a source output impedance by combining two amplifiers having different operational characteristics in parallel. The amplifier circuit includes a first amplifier having an input impedance matching a source and a gain less than a system requirement and a second amplifier having a gain meeting the system requirement and an input impedance substantially higher than the input impedance of the first amplifier, the second amplifier being connected in parallel to the first amplifier. The first amplifier includes an input and an output and the second amplifier includes an input and an output, the input to the first amplifier and the input to the second amplifier being connected to the source. A summer is provided for combining an output signal from the first amplifier with an output of the second amplifier.

Abstract: An RF power amplifier control system is presented herein. The system includes a group of power amplifier modules for amplifying an RF signal. Each group includes first and second group controllers for, when on, controlling the operation of the power amplifier modules including turning on and turning off each of the modules within the group. The first group controller is normally on for controlling the amplifier operation and the second group controller is turned on for controlling the operation only when the first controller is turned off. First and second central controllers are provided for, when on, controlling the operation of the first and second group controllers. The first central controller is normally on to provide the control operation and the second central controller monitors the operation of the first controller and performs the control operation in the event that the first central controller malfunctions.

Abstract: An intermediate amplifier device (20) with a signal amplification stage (21) in a transmission network in which signals can be transmitted from a central station (23) to a number of receivers (24) by way of a number of transmission lines, which are connected to one another in a tree structure, with a number of intermediate amplifier devices of the same type is characterized in that the intermediate amplifier device has a detection device (22) for detecting a malfunction (28) in the transmission line (27) connected to the intermediate amplifier device, a switching device (26) for coupling and uncoupling the transmission line (27) to or from the central station, as well as a delay element (25) with a delay time t.sub.i for the delayed reaction to a malfunction detected by the detection device (22) by means of a correspondingly delayed actuation of the switching device.

Abstract: A modulator (104) varies the duty cycle of a waveform to amplitude modulate information for transmission. A push-pull amplifier (106) in accordance with the invention, preferably constructed of CMOS devices, receives the waveform with a varying duty cycle in order to drive an antenna (108) such that a wireless transceiver can become excited by the oscillating waveform and receive the amplitude modulated signal and demodulate it to obtain the transmitted information. The power generated by the push-pull power amplifier (106) is simply increased or decreased by varying the voltage of the power supplied to the power amplifier or by varying the number of devices driving the antenna (108) in parallel.

Abstract: A power amplifier including: a first amplifier PA2 having an input terminal and an output terminal; a passive circuit PC3 having an input terminal and an output terminal; and a first switch SW2 having a single-pole terminal and two multi-throw terminals, one of the multi-throw terminals of the first switch SW2 being connected to the input terminal of the first amplifier PA2 and the other of the multi-throw terminals of the first switch SW2 being connected to the input terminal of the passive circuit PC3. This makes it possible to provide a power amplifier and a communication unit which can be operated with different frequencies, output powers or modulation types.

Abstract: An automatic dynamic range control circuit is provided with a fixed-gain first circuit means and a variable-gain second circuit means having substantially the same propagation delay as the first circuit means. The automatic dynamic range control circuit holds the peak value of an input signal, selects the first circuit means when this peak value is smaller than a reference signal level, and selects the second circuit means when the peak value exceeds this reference signal level. When the held peak value is smaller than the reference signal level, the second circuit means is operated at the same gain relative to an input signal as the first circuit means by having its gain set by the reference signal. When the held peak value exceeds the reference signal, the gain of the second circuit means is limited by this held peak value and its output level is kept at or below a prescribed level.

Abstract: Waveform synthesizers represent an input waveform as a sequence of numerical codes in a number base, each numerical code comprising a plurality of digits ordered by place significance. A plurality of bilateral amplifiers is provided, a respective one of which is associated with a respective one of the digits. The bilateral amplifiers consume current from the DC power supply and return current to the DC power supply based on the value of the associated digit, to thereby generate an output voltage level that is proportional to the value of the associated digit. The output voltage levels of the plurality of bilateral amplifiers are serially coupled to the load, with a weighting that is based upon the place significance of the associated digit. Waveform synthesizers that are so constructed are capable of theoretical efficiencies of 100% for any signal waveform. These waveform synthesizers may be used efficiently to amplify to a transmit power level or radio signal that varies in amplitude as well as phase.

Abstract: An amplifier circuit (400) includes an input port (402) for receiving a signal and a first balun (404) for splitting the signal into first and second signals. First and second amplifiers (406, 408) are coupled to outputs of the first balun (404) for respectively amplifying the outputs of the first balun (404) to generate first and second amplified signals. Second and third baluns (410, 412) are coupled, respectively, to outputs of the first and second amplifiers (406, 408) for splitting, respectively, each of the first and second amplified signals into in-phase and out-of-phase components.

Abstract: A method and apparatus for efficient power amplification over a wide dynamic range and for a number of modulation formats includes a carrier amplifier (30) and a peaking amplifier (40). The carrier amplifier (30) operates with a bias generated by an envelope amplifier (80) which amplifies the envelope of an input signal as generated by an envelope detector (70). The peaking amplifier (40) operates with a fixed bias. The outputs of the carrier amplifier (30) and the peaking amplifier (40) are combined using an impedance transforming network (50). Envelope amplifier (80) can be turned on for high efficiency low power level operation, or it can be turned off for standard Doherty-type operation.

Abstract: A circuit switches a capacitive value in an exclusive manner to a selected integrated amplifier among a plurality of integrated amplifiers. The circuit includes a first current generator connected between a first supply node and a first node of the circuit, and a second current generator connected between a second supply node and a second node of the circuit. The second current generator is electrically in parallel with the capacitor. An array of switches equal in number to the integrated amplifiers are exclusively switched ON for connecting a directly biased diode between the first node and the second node. Each integrated amplifier has a supply node coupled to a connecting node between a respective diode and a respective connecting switch of the array of switches.

Abstract: A programmable combiner including a first terminal providing a radio frequency input signal, a second terminal providing a radio frequency output signal, a plurality of linear amplifiers in connection therebetween, and switch means coupling individual ones of the plurality of amplifiers in series connection between the first and second terminals in providing a redundancy of continuing circuit operation upon the failure of any one or more amplifiers, and in providing a controllable level of output signal at the second terminal as gain characteristics of one or more of the amplifiers vary, or as different output power signal levels are required.

Abstract: A power amplifier circuit for a radio transceiver has a linear mode amplifier and a saturated (nonlinear) mode amplifier, a diplex matching circuit coupled to the linear mode amplifier for impedance matching and for separating transmitted signals in a plurality of frequency bands, a low pass matching circuit coupled to the output of the saturated mode amplifier and means for selectably placing the power amplifier circuit in a linear mode for or a saturated mode, corresponding to digital and analog modes of operation of the cellular telephone, respectively. In linear or digital mode, the linear amplifier is biased in the on state and the saturated mode amplifier may be biased in the off state. Similarly, in the saturated or analog mode of operation, the saturated mode amplifier is biased in the on state and the linear amplifier may be biased in the off state.

Abstract: A filter with a low-noise amplifier includes: two amplification circuits, a first 3-dB hybrid circuit which is connected to an input side of the amplification circuits, a second 3-dB hybrid circuit which is connected to an output side of the amplification circuits, and a filter which is connected to one input terminal of the first 3-dB hybrid circuit. The other input terminal of the first 3-dB hybrid circuit is subjected to matched termination. A signal is inputted to an input terminal of the filter and is outputted from one output terminal of the second 3-dB hybrid circuit and the other output terminal of the second 3-dB hybrid circuit is subjected to matched termination.

Abstract: A facility (VOR) is disclosed for combining and amplifying two broadband signals which are received from different transmission networks (NET1, NET2) and are transmitted in transmission channels separated in frequency. The facility (VOR) contains a broadband amplifier (BV), a preamplifier (VV), and a frequency filter unit (FW). The preamplifier (VV) and the frequency filter unit (FW) condition the signals to be amplified and establish an optimized signal-to-noise ratio between the two combined broadband signals: The preamplifier adapts the level of one of the signals to the level of the other signal, e.g., to the same value, whereby a linear and increased amplification is achieved in the broadband amplifier, and the filtering of the signals in the frequency filter unit prevents interfering signals, e.g., noise, contained in said one signal from getting into the frequency band occupied by the other signal and vice versa when the two signals are combined.

Abstract: A redundancy combiner assembly has two amplifiers connected in parallel along a waveguide path to a hybrid. The hybrid is connected through a transfer switch to an antenna. The hybrid contains a movable coupling plate. The coupling plate has a coupling array to allow combining of signals of the amplifiers in one position. When one of the amplifiers fails, the coupling plate is replaced by a metal wall and the output from the failed amplifier is directed by the switch to a dump load while the output from the operating amplifier is directed to the antenna. The assembly is controlled by a controller, which monitors the amplifiers and controls the movement of the coupling plate and the switch.

Abstract: An amplifier circuit having a high linearity mode of operation and a high efficiency mode of operation. The amplifier circuit comprises an amplifier having a variable active device periphery and a variable supply voltage; and a control circuit, coupled to the amplifier, for decreasing the variable active device periphery and increasing the variable supply voltage when in the high linearity mode of operation, and for increasing the variable active device periphery and decreasing the variable supply voltage when in the high efficiency mode of operation.

Abstract: An RF power amplifier includes a first monitoring circuit that is coupled to an output signal of the power amplifier, and generates a first control signal based on a level of intermodulation distortion in the output signal. The first control signal has a first value when the level of intermodulation distortion in the output signal is less than a predetermined level of intermodulation distortion and second value when the level of intermodulation distortion in the output signal is greater than or equal to the predetermined level of intermodulation distortion. A second monitoring circuit is coupled to the output signal and generates a second control signal based on a power level of the output signal. The second control signal controls a level of the input RF signal so that the power level of the output signal is less than a predetermined power level. A phase shift/hybrid network is coupled to a primary signal path and an auxiliary signal path of the power amplifier.

Abstract: A power amplifier circuit arrangement including a power amplifier, and a bypass network for bypassing an RF-input signal around the power amplifier when excess gain and output power are not needed. When the bypass network is used, the power amplifier is turned off. A circulator connects the bypass network to the power amplifier output, thus removing the requirement of an output switch. The RF-input signal enters the circulator which routes the signal toward the output of the power amplifier. Because the amplifier is off, its output appears as a high impedance and reflects the signal back to the circulator. The circulator routes the reflected signal the signal output.

Abstract: The inventive LINC amplifier provides substantially linear amplification from two nonlinear amplifiers by decomposing the original signal into two constant amplitude envelope, phase varying signals, which, when combined, constructively and destructively interfere to re-form the original signal. The output of the LINC amplifier, which is to be transmitted via an antenna, is an amplified form of the original signal. The inventive LINC amplifier utilizes a digital control mechanism to control and adapt a digital compensation network that directly compensates for the imperfections of the analog RF environment, including the amplifiers. The mechanism monitors the combined amplifier output and adjusts the signal components in order to precisely compensate for any differences in the characteristics of the separate signal paths which would cause the combination not to accurately represent the original signal.

Abstract: A computer program product is configured to control a modular transmission system having a control processor and at least N power amplifier modules, each having a controller submodule, wherein the system receives an input signal which may be a single carrier or multiple carriers. The signal is passed to a one-by-N divider which divides the signal N ways. Each of the N divided signals are independently amplified by the power amplifier (PA) modules "slices" (i.e., PA modules) that includes an RF amplifier module, a microcontroller module, and a power supply module, all of which are tightly coupled via a plurality of signal, power, control, and status connections. Each the PA slices amplifies its respective input signal and outputs a respective radio frequency output signal at a predetermined power level as controlled by the microcontrol module, the driver, and the system controller, or a network manager via a system input/output interface.

Abstract: A direct detection receiver for a passive microwave and millimeter wave radiometric imaging system. The receiver includes a balanced switch low-noise amplifier (BSLNA). A front-end, low-noise amplifier (LNA) is inserted before the BSLNA to achieve a low-noise figure, as well as provide sufficient gain to minimize the input noise figure degradation due to loss of the BSLNA. A high-electron mobility transistor (HEMT) diode is used as a power detector. The front-end amplifier, BSLNA and diode are process compatible for monolithic integration.

Abstract: A very-wide-dynamic-range amplifier with very low-noise in the high-gain mode and very high-input-overload in the low-gain mode. The amplifier utilizes two parallel signal paths, one a high-gain, low-noise path and the other a low-gain, high-input-overload path. Each path includes a gain-control capability so that the gain of each path, and the contribution of the gain of each path to the overall gain of the amplifier may be smoothly varied from a very low-gain to a very high-gain. Specific embodiments including input impedance matching capabilities are disclosed.

Abstract: A device for amplifying signals comprising at least two amplifier circuits (20, 30, 40, 50) as well as means for precluding interference between the amplifier circuits (20, 30, 40, 50). The amplifier circuit (20, 30, 40, 50) is provided with at least first and second modules (109, 110, 112) which are arranged in cascade, each module (109, 110, 112) being provided with an earth point (i, c, p). The means for precluding interference comprise at least one global earth point (60) and a number of earth connections (70, 80, 90) between the earth points (i, c, p) of corresponding modules (109, 110, 112). The global earth point (60) is connected to the individual earth connections (70, 80, 90).

Abstract: A multicarrier linear RF power amplifier incorporating an improved signal splitter and an improved signal combiner is disclosed. The amplifier comprises a plurality of wedge-shaped amplifier modules. When such modules are radially disposed and abutted against one another, the inwardly facing edges of the modules collectively define a central or axially-located opening. An improved signal splitter, signal combiner, or dual splitter/combiner is advantageously disposed in the axially-located opening. The signal splitter or signal combiner is a conductor arrangement comprising a plurality of equal length conductors radially disposed on a dielectric substrate. The conductor arrangement is advantageously disposed within a suitably-configured housing. The housing is disposed within the axially-located opening.

Abstract: The invention relates to a configuration of power amplifiers comprising firstly N inputs and N outputs, and secondly N amplification channels. The configuration is such that all of the amplification channels have substantially the same power even if the input signals are of different powers. Each amplification channel has at least one cell comprising two preferably identical amplifiers connected to first and second ports of a coupler having a third port constituting the output of the cell. An input coupler is preferably also provided having one port that constitutes the input of the cell and two other ports respectively connected to the inputs of the amplifiers. Each cell includes means for recombining the signals on the ports of the output coupler in such a manner as to maximize the output power in the event of one of the amplifiers breaking down.

Abstract: A distributed amplifier (10) configured to amplify an input signal (20) is presented. Within the amplifier (10), a first input phase-shift element (40) shifts the input signal (20) into a first shifted input signal (56). A first active element (18'), coupled to the first input phase-shift element (40), amplifies the first shifted input signal (56) into a first amplified signal (58). A second phase-shift element (42), coupled to the first input phase-shift element (40), shifts the first shifted input signal (56) into a second shifted input signal (62). A second active element (18"), coupled to the second phase-shift element (42), amplifies the second shifted input signal (62) into a second amplified signal (64). A first output phase-shift element (44), coupled to the first active element (18'), shifts the first amplified signal (58) into a first shifted amplified signal (60).

Abstract: A self balancing matrix amplifier is provided in which a plurality of input signals are divided with an input transform matrix, amplified by a number of amplifiers, and recombined with an output transform matrix to form amplified versions of the input signals. One of the inputs is set aside as a monitor input, and this is connected to the characteristic impedance of the system. The output corresponding to this input is monitored for gain imbalances which should be zero if the entire matrix amplifier is perfectly balanced. Then, on the basis of the monitored phase and gain imbalances, attenuators and phase adjusters in series with each of the amplifiers are iteratively controlled so as to insert phase shift or gain/loss so as to reduce the monitored phase and gain imbalances.

Abstract: A power combiner including a plurality of phasing transmission lines (122) supporting a set of amplifiers (103-105) coupled thereto, and a plurality of matching transmission lines (123-124). The set of amplifiers (103-105) have a selectable number of amplifiers between a minimum and a maximum value having gain levels between a minimum and a maximum value. Each of the matching transmission lines (123-124) is coupled to one of the phasing transmission lines (122) at one end and coupled to a common node (126) at the other end. Each of the matching transmission (123-124) lines has a characteristic impedance determined according to a function of the minimum and the maximum number of amplifiers in the set of amplifiers (103-105) and the minimum and maximum gain levels in the set of amplifiers (103-105).

Abstract: A LINC amplifier of a radio frequency transmitter provides substantially linear amplification from two nonlinear amplifiers by decomposing the original signal into two constant amplitude envelope, phase varying signals, which, when combined, constructively and destructively interfere to re-form the original signal. The output of the LINC amplifier, which is to be transmitted via an antenna, is an amplified form of the original signal. The LINC amplifier uses a digital control mechanism to control and adapt a digital compensation network that directly compensates for the imperfections of the analog RF environment, including the amplifiers. The mechanism monitors the combined amplifier output and adjusts the signal components in order to precisely compensate for any differences in the characteristics of the separate signal paths which would cause the combination not to accurately represent the original signal.

Abstract: A LINC amplifier of a radio frequency transmitter provides substantially linear amplification from two nonlinear amplifiers by decomposing the original signal into two constant amplitude envelope, phase varying signals, which, when combined, constructively and destructively interfere to re-form the original signal. The output of the LINC amplifier, which is to be transmitted via an antenna, is an amplified form of the original signal. The LINC amplifier uses a digital control mechanism to control and adapt a digital compensation network that directly compensates for the imperfections of the analog RF environment, including the amplifiers. The mechanism monitors the combined amplifier output and adjusts the signal components in order to precisely compensate for any differences in the characteristics of the separate signal paths which would cause the combination not to accurately represent the original signal.

Abstract: In a power amplifier apparatus comprising four amplifiers, each amplifier is adapted to amplify the half-wave output signal of a first differential amplifier by means of second and third output amplifiers (2, 3) to drive load (4) by their output amplifying signals and add the output amplifying signals by means of a non-linear circuit (5) in order to control the output DC voltage with the output signal of a second differential amplifier (6) according to the difference between the signal obtained by the non-linear addition and reference value Vref. Feedback signals X and Y of the left front first differential amplifier (1LF) and feedback signals X' and Y' of the right rear first differential amplifier (1RR) are applied to a single clip detection circuit 9 so that any clip in the output signal of the first and second output amplifiers can be detected by means of the feedback signals X, Y, X' and Y'.

Abstract: The transmitter is built according to the LINC principle and has two parallel signal branches, each of which includes an amplifier (V1, V2) and a phase modulator (PM1, PM2). A dividing network (WE) is provided which divides the received signal (DI) between both signal branches and a combining device (KB) which adds the output signals (S11, S22) of both signal branches to form a sum signal (SS). In order to control the phase error in both signal branches the dividing network (WE) is designed so that the assignment of the received signal components (S1, S2) in both signal branches is periodically exchanged at a predetermined cycle frequency (fc). The amplitude modulation of the sum signal (SS) generated by the cyclic exchange of the input signal components (S1,S2) is detected and the phase depending on it in at least one of the signal branches is changed so that amplitude modulation is minimized.

Abstract: The invention presents a high efficiency linear power amplifier of plural frequency bands reduced in the number of parts and elements, simplified in the circuit construction, and saved in the circuit space, and in FIG. 1, signals entering from a common input terminal 1 in frequency bands A and B are matched in both frequency bands A and B in a wide band matching network 2, amplified in a pre-amplifier 3, put into a common terminal 4a of a switch circuit 4, and the signal in frequency band A is put into a changeover terminal 4b, matched in a matching network 5 and amplified in a post-amplifier 6, and its output is matched in a post-matching network 7 and sent out into an output terminal 8, while, similarly, the signal in frequency band B is put into other changeover terminal 4c of the switch circuit 4, matched in a matching network 9, amplified in a post-amplifier 10, and its output is matched in a post-matching network 11 and is sent out into an output terminal 12.

Abstract: A broadband linearizer for use with a power amplifier. The broadband linearizer includes a broadband linearizer bridge, a preamplifier/attenuator, a post amplifier/attenuator, and a control circuit. The broadband linearizer bridge includes a power divider and a power combiner interconnected by linear and nonlinear arms. The linear arm has a phase shifter, a passive equalizer, and a first delay line that are serially coupled together. The nonlinear arm has a distortion generator, an attenuator and a second delay line that are serially coupled together. The control circuit controls respective settings of the broadband linearizer bridge, preamplifier/attenuator and post amplifier/attenuator. The control circuit provides bias circuitry and sends command and telemetry signals to control operation of the broadband linearizer. The broadband linearizer provides for independent, flexible gain and phase control that can mate with different kinds of power amplifiers having various gain and phase performance.

Abstract: A three-way phase shifting power coupler (20) processes a primary signal (26) to provide first, second, and third secondary signals (32, 38, and 44) of substantially equal amplitudes. The first and second secondary signals (32 and 38) are phase shifted to be in-phase relative to the primary signal (26). The third secondary signal (44) is phase shifted to produce a quarter-wavelength difference between third secondary signal (44) and the first and second secondary signals (32 and 38). First, second, and third secondary signals (32, 38, and 44) are provided for distribution into a multi-stage amplifier (22). The power coupler (20) is preferably implemented in microstrip.

Abstract: Amplifier-induced intermodulation distortion (IMD) is reduced by encoding a multi-frequency input composite signal into multiple encoded signals that vary from each other in their power amplitudes as a function of frequency, amplifying the encoded signals, and then decoding them in a complementary fashion so as to differentiate between the amplified signal components and the IMD components. The amplified signal components are coherently combined to separate them from the IMD components, which are incoherently combined. The input signal is preferably encoded by dividng it into multiple divided signals, introducing relative phase shifts between the divided signals that vary as a function of frequency, and combining the divided and phase shifted signals with each other in a Butler matrix prior to amplification. The phase shifts are introduced by means of time delays that are preferably equal to integer multiples of 4.PI. divided by the input signal bandwidth.

Abstract: A system and method for providing distributed amplification of a plurality of input signals is disclosed. The preferred embodiment of the disclosed invention utilizes two substantially different matrixes to dissect an input signal for amplification and subsequent recombination. The unique matrixes disclosed provide for the distributed amplification of any even number of input signals, therefore reducing the number of linear power amplifiers required where a number of input signals other than a power of two are used.

Abstract: A power amplifier (517) for amplifying an operating signal includes an amplifier (538), an amplifier (540), and a power combiner (518) with harmonic selectivity. The power combiner (518) includes a transmission line section (541), a transmission line section (545), and a resistor (554). The transmission line section (541) is coupled to an amplifier output of the amplifier (538), and the transmission line section (545) is coupled to an amplifier output of the amplifier (540) and to the transmission line section (541). A capacitor (546) is coupled in parallel to a transmission line section (542) of the transmission line section (541), and a capacitor (548) is coupled in parallel to a transmission line section (544) of the transmission line section (545).

Abstract: Waveform synthesizers represent an input waveform as a sequence of numerical codes in a number base, each numerical code comprising a plurality of digits ordered by place significance. A plurality of bilateral amplifiers is provided, a respective one of which is associated with a respective one of the digits. The bilateral amplifiers consume current from the DC power supply and return current to the DC power supply based on the value of the associated digit, to thereby generate an output voltage level that is proportional to the value of the associated digit. The output voltage levels of the plurality of bilateral amplifiers are serially coupled to the load, with a weighting that is based upon the place significance of the associated digit. Waveform synthesizers that are so constructed are capable of theoretical efficiencies of 100% for any signal waveform. These waveform synthesizers may be used efficiently to amplify to a transmit power level or radio signal that varies in amplitude as well as phase.

Abstract: An amplifying device has a decibel gain that evolves quasi-linearly as a function of the digital value of a control word C(O:M-1). The device includes: an amplifying stage with K amplifiers having mutually different decibel gains, the gain in decibels of each amplifier being a multiple of the same value G0; a switching stage with K switches; a gain-controlled amplifier having a gain which varies between 0 and G0 as a function of the value of the N least significant bits (C(O:N-1)) of the control word received at its digital input; and a decoder receiving a digital word including the (M-N) most significant bits (C(N:M-1)) of the control word. The decoder has K logic outputs controlling the K switches.

Abstract: In a power amplifier apparatus, a positive output signal of left front output amplifier (2LF), a negative output signal of left rear output amplifier (3LR), a negative output signal of right front output amplifier (3RF), and a positive output signal of right rear output amplifier (4RR) are applied to an adder (9), which selects the signal showing the highest level out of the four signals and generates a voltage corresponding to the selected signal. Switching power source (10) is adapted to operate according to the output signal of the adder (9) and produces a power source voltage to each of the high efficiency amplifiers. The positive output signal of the left front output amplifier and that of the right rear output amplifier are identical and substantially in-phase, whereas the negative output signal of the left rear output amplifier and that of the right front output amplifier are identical and substantially in-phase.

Abstract: A system and method for providing distributed amplification of a plurality of input signals is disclosed. The preferred embodiment of the disclosed invention utilizes two signal path matrixes having signal combiners, hybrid combiners, and phase shifters to dissect an input signal for amplification and subsequent recombination. The unique matrixes disclosed provide for the distributed amplification of any number of input signals factorable as a product of prime numbers including an odd prime number factor, therefore reducing the number of linear power amplifiers required where a number of input signals other than a power of two are used.

Abstract: A configuration of audio system components, utilizing standard amplifier components, wherein the audio system remains balanced through the speaker input terminals. For each channel of the system, a preamplifier produces a balanced output signal. Two power amplifiers or similar devices are conventionally configured to accept positive and negative input signals. The negative signal output of the preamplifier is connected to the positive input terminal of one of the power amplifiers, and the positive output signal of the preamplifier is connected to the positive input terminal of the other power amplifier. The negative and ground input terminals of both power amplifiers are connected to system ground. The connections between the preamplifiers and the amplifiers may be effected by a unique cable designed for this purpose.

Abstract: A radio frequency amplifier, for amplifying a radio frequency signal, comprises a plurality of active element groups, each comprising one or more active elements for amplifying a signal, with input terminals of said one or more active elements being combined to form a single input terminal and output terminals of said one or more active elements being combined to form a single output terminal and bias control means for controlling bias conditions of said plurality of active element groups arranged in such a manner that at low power output deterioration of the gain and distortion characteristics of the amplifier is avoided and sufficiently low power consumption can be achieved by switching the bias voltages of each of the active element groups of the high-frequency amplifier individually between an operating voltage and an off voltage.