Abstract: A spatial power combiner includes a circularly corrugated horn 26, a meniscus lens 28, an amplifier array 16, and a layer of microwave absorbing material 34 on a housing interior 32. The lens 28 receives polarized microwave radiation from the horn 26 and collimates it, renders it in phase and with nearly uniformly amplitude, and distributes it across the lens aperture. The amplifier array 16 amplifies the radiation and re-radiates it, orthogonally polarized, to the lens 28, which focuses it back down the horn 26. An array of parasitic micropatches 24 between the lens 28 and amplifier array 16 provides impedance matching. A quarter-wave anti-reflecting coating 30 covers both surfaces of the lens 28. The microwave absorbing material 34 reduces or prevents resonance of higher order modes.

Abstract: A broadband amplifier includes an amplifier device and input and output networks formed of microstrips. The impedance of the output microstrip is chosen by taking the geometric mean of the real parts of one of the scattering parameters of the amplifier device, at the lower and upper limits of the frequency range of interest, and by taking the geometric mean of the system impedance with the result obtained previously. The final result of these calculations is the impedance of the output network. The impedance of the input network is made to be at least twice, and preferably twice, the impedance of the output network. The amplifier is also provided with a slope compensation circuit. It has been discovered that an amplifier designed in this manner exhibits remarkable flatness over a five-octave range. The amplifier circuit is therefore suitable for use in cable television and other broadband telecommunications applications, where the frequency range of interest may be 30 MHz to 1000 MHz.

Abstract: An amplifier extracts the maximum power from a plurality of identical three-terminal electronic amplifying devices, herein coined "cells," by additively combining their power contributions. The amplifier, herein coined a "non-uniformly distributed power amplifier," is a distributed amplifying circuit in which the transmission line impedances between adjacent electronic amplifying devices varies throughout the distribution in a prescribed manner so as to optimize the power output and/or amplifying efficiency of the distribution. The distribution may be constructed in one, two, or three dimensions but will always produce an overall mid-band power gain which is equivalent to the sum of the gains of the devices contained in the distribution of an overall power output which is equal to the number of devices times the power contribution of a single contributing device.

Abstract: An amplifier circuit having an impedance matching circuit coupled between a transistor having an element impedance of Z.sub.Tr and a first transmission line having a characteristic impedance of Z.sub.0, the impedance matching circuit including a second transmission line having a characteristic impedance Z.sub.T0 .apprxeq.(Z.sub.Tr .times.Z.sub.0).sup.1/2 and a length of a quarter wavelength, and a high-harmonic processing circuit disposed at the connection of the second transmission line to the first transmission line. The high-harmonic component processing circuit has two parallel stubs each having a certain characteristic impedance and a released tip end, the two parallel stubs having length of one-eighth wavelength and one-twelfth wavelength, respectively.

Abstract: An amplifier circuit (10) receives a differential input signal and provides an amplified differential signal. A converter circuit (14) is responsive to the amplified differential signal and provides a single-ended signal. An output stage (16) is responsive to the single-ended signal for providing an output signal of the amplifier circuit. The output stage provides bias cancellation for the single-ended signal by injecting a current equal to the bias requirement of the input transistors (20, 38). The bias cancellation maintains a high input impedance and high gain and output drive for the output stage.

Abstract: A microwave amplifier includes a field effect transistor having its source grounded. The drain of the transistor is connected through a first inductor of gold wires to an output-side matching circuit, while the gate of the transistor is connected through a second inductor of gold wires to an input-side matching circuit. A series circuit including a capacitor and a third inductor is disposed near the input-side matching circuit and is connected between the junction of the input-side matching circuit and the second inductor and a reference potential.

Abstract: A circuit for compensating for the phase velocity differences caused by the layout arrangement of a high-frequency transistor circuit comprises a shunt reactive element 60 coupled to an input or output terminal 51 of a first transistor 48 in a sequence of transistors arranged between input 42 and output 54 transmission lines. The shunt reactive element provides adjustment in phase such that signals traversing various routes through the circuit add in phase at the circuit output. The circuit may also include series resonant circuits 102 between the input terminals 44 and 46 of transistors in such a sequence and between output terminals 51 and 52 of transistors in such a sequence. The series resonant circuits appear as short circuits at certain frequencies and thereby may be used to virtually eliminate the phase progression along transmission lines linking transistors in the sequence.

Abstract: A semiconductor device microwave integrated circuit includes at least a transistor stage which stage includes a microwave matching circuit and a d.c. bias circuit interconnected at a link node (A). The transistor stage further includes a stabilizing circuit which includes an open stub line connected to the link node. The open stub line connected to the link node is a .lambda./4 line which at the operating frequency imposes a short circuit on the link node. A matching circuit made up of a low-value resistor connected to ground in the microwave mode through a d.c. isolating capacitor is connected to the link node. A .lambda./4 line of the radial type (.lambda./4 radial stub) provides broadband operation.

Abstract: An amplifier, suitable for use in a limited band at microwave frequencies, incorporates a single lossless feedback coupling element between the input port and output port of the gain circuitry. The feedback element is formed of two coextending conductors of a length on the order of a quarter wavelength of the center frequency of the band. An input signal is coupled to the gain element through one of the feedback conductors. An output signal is coupled from the output port of the gain element through the other of the conductors of the feedback element. Relatively low closed loop gain, on the order of 10 dB, is achievable over the specified band at center frequencies on the order of 800-1000 MHz.

Abstract: A switchable impedance circuit and method for maintaining a controlled signal line (e.g. RF transmission line) impedance at a circuit node includes a circuit and method for connecting a switchable impedance in shunt or series, or in a shunt and series combination. The switchable impedance can be selectively switched, e.g. "on" or "off", when the circuit is being powered up or down, or both, so as to maintain the desired, e.g. characteristic, impedance at the node of the signal line to which it is connected, for example by providing the complex conjugate of, or vectorially matching, any complex impedance present at such node, thereby advantageously helping to minimize undesirable transient signal effects, such as circuit ringing or oscillator frequency pulling.

Abstract: An RF voltage/current sensor apparatus comprising a plurality of transmission lines coupled through resistive means to voltage sense circuitry. The voltage sense circuitry utilizes transistor technology thereby reducing the use of switching relays, transformers and diodes thereby providing an apparatus operational over a frequency range from approximately two megahertz to two gigahertz.

Abstract: An improved Doherty amplifier for operation at microwave frequencies using microstrip circuit technology and gallium arsenide devices to achieve greater efficiency and linearity. The circuit divides the input power equally between a carrier amplifier and peak amplifier with a quarter-wave delay at the input to the peak amplifier insuring that the output power of the two amplifiers will be in phase at the load. A three-port network combines the phase-delayed carrier amplifier output with the output of the peak amplifier. The outputs of the two amplifiers are connected together by a quarter wave transmission line of impedance R. A load of one-half the optimum load (R/2) is attached to the output of the peak amplifier. A quarter-wave line section provides the transition from R/2 to the desired impedance, R. When the peak amplifier is off, its output impedance is infinite and the output power of the carrier amplifier is delivered entirely to the load.

Abstract: A distributed amplifier includes an input side circuit including a plurality of distributed constant lines connected in series between an input terminal and ground and a plurality of source-grounded FETs for switching operation having drains connected to respective junctions of the distributed constant lines, an output side circuit including a plurality of distributed constant lines connected in series between an output terminal and ground, and a plurality of source-grounded amplifier FETs having gates connected to respective junctions of the distributed constant lines of the input side circuit via capacitors and drains connected to junctions of the distributed constant lines of the output side circuit.

Abstract: A high frequency amplifier has a distributed amplifier having a sufficiently wide band and formed on a microwave integrated circuit, and at least one bandpass filter directly connected to the distributed amplifier and formed of a microstrip line having a desired frequency band having a desired center frequency.

Abstract: A microwave amplifier circuit has input and output coupling circuits (21 and 22) designed on quite different matching principles to obtain a circuit compactness similar to a reactively-matched amplifier and cascadable electrical characteristics similar to a distributed amplifier. The input coupling circuit (21) is formed as a bandpass filter network (7a, 7b, 7c, 17a, 17b, 9) supporting a travelling wave to which the amplifying device (3) is capactively connected. This input network (21) terminates in a resistor (9) in which the travelling wave is dissipated. The output coupling circuit (22) is a reactively matched circuit (8a, 8b, 18a, 18b) which also has a bandpass characteristic. By making the input network (21) bandpass (instead of low pass) a large amplifying device (3) can be used, without reducing line impedance and gain.

Abstract: A low noise narrow band amplifier with low power consumption for amplifying radio frequency and microwave signals. The amplifier includes a high frequency transistor that has a cut-off frequency greater than the center frequency of the input signal. The amplifier includes an emitter inductor for low noise and better input match. The amplifier is stabilized for out-of-band high frequency oscillations by a collector inductor and a base inductor. The amplifier is further stabilized unconditionally for out-of-band high frequency oscillations by a stabilizing circuit coupled between the output and ground, including a stabilizing capacitor in series with a stabilizing resistor.

Abstract: A high-frequency amplifier has a semiconductor element for amplifying a high-frequency signal, an input matching circuit connected to an input side of the semiconductor element, and an output matching circuit connected to an output side of the semiconductor element. A stabilizing circuit is connected to at least one of a signal input path between the input matching circuit and the semiconductor element, and a signal output path between the semiconductor element and the output matching circuit. The stabilizing circuit includes a first element having a first end which is short-circuited with respect to a high frequency, a parallel resonant circuit connected in series with a second end of the first element and performing parallel resonance at an operating frequency of the high-frequency amplifier, and a second element connected to a side of the parallel resonant circuit which is opposite to the first element.

Abstract: A microwave cavity closure structure encloses an upper splitter cavity bounded at its top and bottom by, respectively, a rigid metal plate and a flexible sheet metal dish and (b) a lower combiner cavity bounded at its top and bottom by another such dish and another lower such plate. Each such cavity has a central region occupied by a raised circular boss, and the lower plate bounding the bottom cavity mounts, outward of the central boss, two concentric annular sheet metal rings each having a flat top and peripheral flanges extending from the margins of that top down into annular grooves in the lower plate. One or more rings of dielectric posts are disposed in each cavity radially between the central boss therein and the cavity periphery to vertically space at the ring's location the plate and dish of the cavity by a distance determined by the posts, while concurrently permitting the dish to be flexed in the cavity's central region for cavity tuning purposes.

Abstract: A monolithic quasi-optic amplifier is provided for co-linear beam propagation in the millimeter wave frequency range (30-300 GHz). The amplifier comprises a multiplicity of unit cells that act as nearly independent amplifiers. Each unit cell includes a GaAs transistor, a slot antenna, a patch antenna, a microstrip line, and a DC bias provided by a ground plane that routes non-radiating transmission lines without interference. The slot antennas on GaAs provide preferential directionality in receiving the input waves. A vertically polarized input wave couples energy into each unit cell through the slots in the ground plane, through the microstrip lines, and to the base of each transistor. After amplification by the transistors, the signal is fed to the patch antennas, which generate a horizontally polarized output wave. The size of each patch antenna, which is determined by the operating frequency, is approximately 1 mm by 1 mm in GaAs at 44 GHz.

Abstract: Directional couplers 7.sup.1 -7.sup.20 are used to couple power from r.f. power amplifier modules 5.sup.1 -5.sup.20 to a transmission line 6 or other type of resonator, from which it is withdrawn by directional coupler 8. The power withdrawn from the continuous transmission line, which is an integral number of wavelengths at the operating frequency of the modules in length, is less than the power circulating around the transmission line 6. The balance load may be removed to enable the output load to be combined with the output of another r.f. power amplifier operating a different frequency so that e.g. sound and vision signals can be combined at an aerial and, in the latter case, means may be provided for improving the resonance of the main loop 6.

Abstract: In a broadband amplifier having an upper limit frequency of several GHz that is composed of a plurality of transistors connected in parallel, the control terminals (gates) of the transistors are respectively connected to line sections of an input line via an input circuit composed of a plurality of capacitors and appertaining resistors connected in parallel. Outputs (drain terminals) of the transistors are respectively connected to line sections of an output line.

Abstract: In one form of the invention, an amplifier is disclosed, the amplifier comprising: an input transmission line 32; an output transmission line 36,38; at least two active devices 134 distributed between the two transmission lines; a termination 50 connected to an end of the input transmission line 32, the termination 50 comprising a terminating transistor 52 having a first gate terminal 150, a drain terminal 151, and a source terminal 152. wherein the first gate terminal 150 is connected to the input transmission line 32 and the drain terminal 151 is coupled to the first gate terminal 150 through a resistor 58 and a capacitor 56. The termination 50 is preferably characterized by a noise temperature of less than 300.degree. K.

Abstract: A microwave amplifier includes an amplifier, an impedance matching circuit for matching input and output impedances of the amplifier, and an open stub. The impedance matching circuit includes input and output side distributed constant lines each having a length equivalent to a 1/4 wavelength of a signal having the highest frequency in a desired frequency band. The open stub is disposed in the vicinity of the input or output side distributed constant line. The length of the open stub is varied to vary a narrow frequency band in which the maximum gain of the amplifier is attained. In this structure, the return loss is reduced and a uniform tuning in the frequency band is easily carried out using the open stub. In addition, the maximum potential of the amplifier is achieved in the desired frequency band.

Abstract: An active load applied to the gate transmission line termination of distributed power devices reduces the low frequency noise power appearing at the output of the device. The active load, including at least one active device such as a field effect transistor, operates by transforming the input impedance of a low noise amplifier to the desired load impedance. The active load is connected to one end of an input transmission line having a plurality of impedances connected in electrical series. An input terminal is connected to the opposite end. An output transmission line, also having a plurality of impedances connected in series, has an output terminal at one end and a terminating output impedance at the other. A plurality of active devices are connected to junction points between the series connected impedances of the input and output lines.

Abstract: A microwave amplifier includes input-side and output-side matching circuits disposed on the input side and output side of a microwave FET. Each of the matching circuits is a distributed constant circuit including microstrip lines disposed on a substrate of dielectric material. The input-side matching circuit includes a connecting section for connection to the FET. The connecting section comprises a first microstrip line having a first width equal to that of the input-side matching circuit, and a second microstrip line continuous and integral with the first microstrip line and having a second width smaller than the first width. The connecting section connects the input-side matching circuit to the input of the FET.

Abstract: In a thick multilayered wiring board, a coaxial signal wiring pattern is surrounded by upper and lower horizontal grounded conductive layers and vertical grounded conductive layers and the vertical conductive layers of conductive layers which surround the coaxial signal wiring pattern are formed in a photosensitive dielectric layer by a photolithography, whereby matching of characteristic impedance of the pattern is improved and thus crosstalk is reduced.

Abstract: A high-frequency wideband power amplifier, of the type comprising an amplifier stage with at least two transistors mounted as a differential stage, coupled at input and at output to a matching circuit further comprises, in order to convey each bias voltage to the amplifier stage, at least one high-frequency transmission line section with a length close to a quarter of the wavelength of the carrier of the signal to be amplified, the impedance of which, brought in parallel on each transistor, is negligible with respect to the high frequencies and the series impedance of which is negligible in the baseband of the signal to be amplified; the line sections conveying the bias voltages to the input of each transistor are identical to one another in length and in impedance, and the same is the case for the line sections conveying the bias voltages to the output of each transistor.

Abstract: In a power matching network which is used between a load and a transistor amplifier producing at its output end an amplified signal comprising a fundamental frequency signal and odd and even harmonic signals and comprises a matching circuit between the load and a line end, an open-end transmission line is connected to the output end and has a predetermined length shorter than a quarter wavelength of the fundamental frequency signal. An intermediate transmission line is connected between the output and the line ends and has a length of a quarter wavelength less the predetermined length. At least one open-end transmission line is connected to the line end and has a length of a quarter wavelength of the odd harmonic signal which is preferably composed of (2n+1)-th harmonic signals, where n represents integers starting at 1 and ending at a predetermined integer of at least 2.

Abstract: A microwave integrated circuit includes a semiconductor substrate having semiconductor elements, such as transistors, diodes, resistors, and the like, and a passive circuit substrate having passive circuit elements, such as microstrip or coplanar transmission lines, spiral inductors, capacitances, and the like, on its front surface. The passive circuit substrate is mounted on the semiconductor substrate so that the rear surface of the passive circuit substrate faces the surface of the semiconductor substrate on which the semiconductor elements are present, and the semiconductor elements are electrically connected to the elements or grounding conductors of the passive circuit substrate via through-holes or bumps. The passive circuit substrate includes a thin dielectric film having less dielectric loss than the semiconductor substrate, and the passive circuit elements, especially the transmission lines, are disposed on the dielectric substrate.

Abstract: A step attenuator using a PIN diode for use with microwave circuits. The step attenuator circuit provides for stepwise controlling the current applied to the microwave monolithic integrated circuit. The step attenuator circuit comprises a driver circuit and a attenuator circuit coupled thereto. The driver circuit that comprises a temperature sensor, a comparator circuit coupled to the temperature sensor for comparing the temperature value sensed by the temperature sensor to predetermined reference voltages and for providing a plurality of output signals that are indicative of a respective plurality of temperature values sensed by the temperature sensor, and a resistor network coupled to the comparator circuit that is adapted to set the respective values or current provided by the driver circuit.

Abstract: A distributed amplifier produced from monolithic microwave integrated circuit (MMIC) processes employs a bandpass filter structure as opposed to a low-pass filter network to enhance gain, efficiency and output power over wideband operation of 6 GHz to 18 GHz. Derivation of the preferred embodiment is shown from a three port circuit employing bandpass filter image-parameter half-sections.

Abstract: Power amplifier operating at a fixed frequency or a narrow bandwidth and based upon a non-linear gain element. The power amplifier includes a resonant circuit operably connected to the non-linear gain element, the circuit being resonant at a harmonic of substantially the band center frequency of the non-linear gain element and being arranged to dissipate energy resulting from harmonic generation by the non-linear gain element during signal amplification. In a particular aspect of the power amplifier, resonant circuits comprising inductor-capacitor harmonic trap circuits tuned to different harmonics are placed at both the input and the output of a gallium arsenide heterojunction bipolar transistor HBT providing the non-linear gain element.

Abstract: The wave propagation signal transmission device according to the invention comprises two coupled distributed-constant wave propagation lines. The lines include active members of amplifying signals in transit in the form of linear and continuous components in parallel relationship. In particular, a cathode 318, and control grid 320, decoupling/accelerating screen grids 324, 326, receive, at E, HF signals to be amplified, and an anode 322 delivers, at S, amplified signals. Possible uses of the device according to the invention are high power and very wide band HF amplification and the generation of electromagnetic pulses very steep rise front and of long duration.

Abstract: An X-band (8-12.5 GHz) amplifier comprises a bipolar junction transistor (BJT) arranged for receiving an X-band signal, amplifying the signal and providing the amplified signal to further circuitry. Input and output matching networks are advantageously provided for the BJT. Each network may have a first end for connection to a BJT and a second end for connection to a terminal, and may comprise a series connection of a first inductor, a first capacitor and a second inductor extending from the first end to the second end in that order; a third inductor connected between ground and the connection point of the first capacitor and the second inductor; and a second capacitor connected between ground and the second end. The various reactance components may be implemented on a dielectric board, for example by microstriplines and/or shaped cladding portions. An X-band oscillator may comprise the X-band amplifier described above, and a feedback circuit interconnecting an output and an input of the amplifier.

Abstract: A microwave power divider/combiner (10) comprises a preamplifier (12), a first microwave lens (14), a plurality of amplifiers (16), and a second microwave lens (18). The preamplifier (12) is coupled to receive a microwave source signal (20) and amplify it. The output of the preamplifier (12) feeds the first lens (14). The first lens (14) divides the signal received on its input into a plurality of signals of equal amplitude and phase. Each output of the first lens (14) is then provided to an input of a respective amplifier (16) from the plurality of amplifiers (16). The amplifiers (16) amplify the divided signals and output them to the second lens (18). The second lens (18) has a plurality of inputs and recombines the signals on the inputs into a single higher level signal at an output (22). The present invention also provides a compact configuration for the divider/combiner (10) of the present invention with the lenses (14, 18) mounted on top of each other separated by a mounting block (26).

Abstract: A high-frequency power amplifier device is provided in which the number of ground lines on the electronic parts mounting face of a strip line substrate having microstrip lines is reduced or eliminated. Specifically, a metallic cover extending in parallel with the mounting face of the strip line substrate is grounded, and the microstrip lines between this cover and the strip line substrate are electrically connected by connecting means such as capacitors and/or conductors.

Abstract: A circuit for maintaining a constant voltage across and constant current through an RF cavity includes a RF cavity comprising a common-gate or common-base transistor associated with a current control circuit maintains a constant current flowing through the RF cavity. The current control circuit has a current control BJT associated with the RF cavity and a resistor between the emitter of the current control BJT and the negative source voltage of the RF cavity. The current control BJT and resistor operate as a current source or sink as necessary to maintain a constant current flow through said RF cavity. A constant voltage regulation portion of the circuit maintains a constant voltage across the RF cavity and includes a zener reference diode and a voltage regulation BJT.

Abstract: A predistortion linearizer (20) is operative with a microwave signal, as may be provided by signal source (62) to linearize the gain of a power amplifier, such as a traveling-wave-tube power amplifier (74), by introduction of an amplitude and/or a phase distortion to the microwave signal wherein the distortion is inverse to a distortion introduced by the power amplifier, thereby to compensate for the distortion of the power amplifier. The linearizer is constructed of two channels (22, 24) which are operated in parallel but approximately 180 degrees out of phase, with an additional phase increment provided by delay lines (46, 56) to offset one channel from the other channel by a phase difference in a range of approximately 160-200 degrees.

Abstract: In a microwave multistage amplifier, a shield casing (8) has a partition plate (7) integrally moulded with and disposed in the casing (8); microwave amplifiers (5, 6) are arranged on a dielectric substrate so as to locate the partition plate therebetween; and an upper cover plate (11) is provided which can be screwed to partition plate (7). By virtue of the above-mentioned arrangement, it becomes possible to strictly separate rooms defined in the casing from each other and suppress generation of a surface wave mode of the microwave propagation on the dielectric substrate, thereby assuring an isolation between the amplifiers.

Abstract: A circuit for compensating for GaAs FET amplifier gain variations over a frequency band as a function of temperature. The circuit includes a passive equalizer circuit having a fixed gain over the frequency band and an active equalizer circuit having a gain which varies over the frequency band as a function of temperature. The passive and active equalizers are coupled in series. The active equalizer circuit comprises varactor diodes in a low pass filter arrangement with the bias voltage of the varactor being provided by an external driver controlled by a temperature sensitive thermistor. As the value of the varactor's junction capacitance is increased (as a function of the temperature controlled bias voltage), the cutoff frequency of the low pass filter decreases.

Abstract: A high-frequency bias supply circuit includes a plurality of bias supply lines each of which is connected in parallel with others between a corresponding one of selected points along the main signal line and a common bias supply terminal. Each of the bias supply lines has a length and a distance from an adjacent bias supply line different from those of others, the length and the distance being in a range of a 1/3 to 3/8 wavelength of the center frequency.

Abstract: A small-sized, high-efficiency semiconductor amplifier exhibits a satisfactory efficiency characteristic over a wide band and a low output level for secondary and tertiary higher harmonics.

Abstract: A power amplifier device includes m power amplifier units provided in parallel where m is an integer, a distributor for distributing an input signal to the m power amplifier units, and a combining device for combining m amplified input signals output by the m power amplifier to generate an amplified output signal. The power amplifier device includes a group of switches for gradually disconnecting the m power amplifier units from the distributor and the combining device and for gradually connecting the m power amplifier units to the distributor and the combining device.

Abstract: A conical TEM power divider/combiner (10) comprises an input port (12), a first circular waveguide (14), a coaxial device (16), a plurality of amplifiers (18), a plurality of cooling fins (20), a second circular waveguide (22), an output port (24), a conical dividing waveguide (42, 32), a first parallel plate waveguide (40, 50), a second parallel plate waveguide (40, 52) and a conical combining waveguide (34, 44). The input port (12) is coupled to the first circular waveguide (14). The first circular waveguide (14) is in turn coupled to the coaxial device (16). The coaxial device (16) divides the signal using the conical dividing waveguide (42, 32), a first parallel plate waveguide (40, 50), and a first plurality of striplines (54). The striplines (54) couple the first parallel plate waveguide (40, 50) to the inputs of the plurality of amplifiers (18). The amplifiers (18) each amplify a respective divided signal and output the result to the second the second parallel plate waveguide (40, 52).

Abstract: A microwave power amplifier having application in multiple beam phased antenna array systems including a biasing means connection to the base of a microwave transistor being responsive to radio frequency signals applied to the amplifier to automatically adjust the transistor bias level to maintain constant amplifier gain. The biasing means includes two voltage regulators with their outputs capacitively coupled via a fixed resistor having a value determined by the characteristics of the transistor, the base of the transistor being connected to the biasing means at the junction of the resistor and the capacitive coupling of one of the regulators. The mode of operation of the power amplifier gives rise to a highly efficient linear system while under effective Class B (non-linear) bias.

Abstract: A high power field effect transistor (FET) amplifier which can provide a high gain over a wide bandwidth of a microwave range includes, on a first substrate on which a grounded-source field effect transistor is disposed, a series combination of an inductor and a capacitor connected between the gate of the FET and ground. The gate of the FET is coupled to an input impedance matching circuit disposed on a second substrate. The drain of the FET is coupled to an output impedance matching circuit disposed on a third substrate.

Abstract: In a hybrid microwave integrated circuit in which an FET and an LC resonance circuit are integrated, the LC resonance circuit includes an inductor and a capacitor disposed on a substrate having a smooth surface which ensures that the dimensional precision of the inductor will be in a range of.+-.several microns when it is formed on the substrate. Then, the substrate, on which the LC resonance circuit is formed, is mounted on or buried in a high frequency signal transmitting substrate. Therefore, variation in resonant frequency of the LC resonance circuit are reduced, whereby deteriorations in characteristics, such as efficiency, output power and the like, are reduced. In addition, since the LC resonance circuit is reduced in the size and cost of the whole circuit are reduced.

Abstract: The power amplifying circuit embodied by the invention is composed of a single-unit circuit capable of varying own bias condition, and yet, more than two kinds of amplifying modes can selectively be activated merely by applying a single-unit power amplifying circuit. Concretely, the power amplifying circuit embodied by the invention comprises the following, a power amplifying transistor, a base-side transmission line, a resistance element connected to the base-side transmission line, the first switching element accommodating current path formed in series against the resistance element so that the first potential can be delivered to the resistance element, the second switching element which is inserted between the base-side transmission line and the second potential, and a circuit means for varying the value of a base potential of the power amplifying transistor by means of opposite switching operations performed by the first and second switching elements.

Abstract: A distributed circuit includes a plurality of pairs of cascode coupled first and second transistors with each transistor having base, emitter, and collector electrodes. The first transistor of each pair is disposed to have a first one of emitter and collector electrodes coupled to a reference potential and the second one of said transistors of each pair is disposed to have the base electrode coupled to a reference potential with the second one the collector and emitter electrodes of the first transistor of each pair being coupled to the emitter electrode of the corresponding second transistor of each pair. The network further includes an input propagation network disposed to successively couple the base electrode of each one of the first transistors of each pair of transistors to an input terminal and an output propagation network disposed to couple the collector electrodes of each one of the second transistors of each one of the pair of transistors to an output terminal of the circuit.

Abstract: A multistage amplifier for amplifying an input signal so as to output an amplified signal. The multistage amplifier is comprised of a plurality of transistors that are monolithically formed around a central VIA hole. Predetermined electrodes of the respective transistors are electrically connected to each other in the area immediately surrounding the central VIA hole and are connected to the VIA hole itself. This allows for a reduction of the number of VIA holes used over conventional methods. The distance between the central VIA hole and the predetermined electrodes of each of the transistors is minimal, as is the wiring pattern of each of the electrodes. No scattering is caused by the characteristics of the transistors, as they are monolithically formed in the same manufacturing process.