73 results about "Load pull" patented technology

An automatic, frequency selective microwave tuner, used for load pull transistor testing, is capable of generating independently controllable reflection factors, both in amplitude and phase, at several, harmonic or not, frequencies simultaneously. The tuner employs horizontally and vertically adjustable high Q resonant probes and replaces, when used in harmonic load pull set-ups, otherwise required combinations of wide-band tuners with harmonic rejection tuners or wide-band tuners and frequency discriminators (diplexers or triplexers).

The present invention discloses a harmonic rejection load pull tuner. The tuner of the invention has a large-band tuner having an input and an output, and a transmission line having a longitudinal axis. The transmission line has an input connected to the output of a DUT and an output connected to the input of the large-band tuner. In parallel with the transmission line is at least one stub, the at least one stub having a length adapted to reflect out an nth order harmonic of a base frequency, where n is an integer greater than 1. The tuner of the present invention can be used to perform input or output characterisation (or both) of a DUT, by selectively reflecting out at least one harmonic frequency of the base frequency. Consequently, the characterisation of the DUT is improved, since the effects of the harmonics are considerably reduced. The present invention also concerns a method for performing input or output characterisation.

An automatic, electromechanical microwave tuner, used for load pull transistor testing, employs three horizontally and vertically adjustable RF probes; the tuner creates very low mechanical vibrations, because it is capable of generating all microwave reflection factors required for complete load pull and noise measurement operations, using only vertical probe movement; it also provides high tuning dynamic range, large frequency bandwidth and continuous choice of tuning target areas.

The invention relates to a device and method for researching the metallic hydrogen permeation behavior, in particular to a device and method for researching the hydrogen permeation behavior of metal subjected to dead-load pulling stress in a gaseous medium, and the device and method are used for researching the interactive influence of pulling stress and a gaseous environment on the metallic hydrogen permeation behavior. The device comprises a heating device, a stretching device, an electrolytic bath and a liquid / gas storage bottle. The method comprises the steps of: nickel-plating a single side of a test piece to be tested, and fixing the test piece between a lower opening of an anode pool and an upper opening of an environmental pool, wherein the nickel-plated layer of the test piece faces the environmental pool; and providing dead-load pulling stress for the test piece by the stretching device. An experimental medium in the anode pool is a NaOH solution. An experimental solution inthe environmental pool forms a gaseous medium environment under the action of water bath. The device and method provided by the invention can be used for researching the hydrogen permeation behavior of a metallic material subjected to dead-load pulling stress in the gaseous medium, the control of the magnitude of the pulling stress and the environment and atmosphere can be realized, and the deficiency that the influence of a stressed state and the gaseous environment on the metallic hydrogen permeation behavior cannot be measured through the traditional electrolytic bath is made up.

A mobile communication device and an impedance matching method thereof are provided. The mobile communication device includes an antenna, a power amplifier, a tunable matching circuit, a power detection circuit and a controller. The tunable matching circuit determines an output impedance encountered by a radio frequency (RF) signal transmitted by the power amplifier to the antenna when the RF signal enters the tunable matching circuit. The power detection circuit detects a forward power of the RF signal entering the antenna and a reflected power of the antenna. The controller tunes the tunable matching circuit according to a frequency range currently used by the mobile communication device, the forward power and the reflected power to steer the output impedance toward a corresponding load-pull impedance that the power amplifier has in the frequency range.

Measurement arrangement and method for active load pull measurements of a device under test (1). A wideband analog-to-digital conversion block (3) is provided for obtaining measurement data. First and second injection signal generators (7, 8) are connected to a source side and a load side of the device under test (1). This set up allows to create predetermined reflection coefficients at reference planes of the device under test (1). Injection signal parameters as determined are converted into the injection signals at the source and load side by digital-to-analog conversion. The wideband analog-to-digital conversion block (3) is further arranged for analog-to-digital conversion of the intermediate frequency signals to obtain the actual measured reflection coefficient versus frequency functions with a first frequency resolution. The first frequency resolution applied in the analog-to-digital conversion is equal to or better than a second frequency resolution applied in the digital-to-analog conversion.

Low loss current and voltage probes are integrated in parallel plate airlines (slablines) to be used either as separate modules inserted between tuner and DUT in load pull test setups, or integrated in the impedance tuners themselves. The probes are inserted orthogonally at exactly the same reference plane relative to the DUT, maximizing bandwidth and the minimizing deformation of the detected electric and magnetic fields. The probes are used to detect the actual voltage and current waveforms and feed into an amplitude-and-phase calibrated high speed oscilloscope, including several harmonic frequencies. The actual real time voltage and current time domain waves are transformed into the frequency domain using fast Fourier transformation (FFT), de-embedded to the DUT reference plane and inverse transformed into the time domain using inverse Fourier transformation (FFT−1). The result of this real-time operation is the actual dynamic load line of the DUT at its terminals.

High reflection load pull tuners are proposed, which include two or more RF probes, placed in series into the same slotted airline (slabline) and being controlled simultaneously horizontally and vertically by remote electric control, allowing the creation of controlled reflection factors which are distributed over and cover the entire Smith Chart, from very low reflection factors up to very high reflection factors and a method allowing to align such tuners and to calibrate such tuners on a vector network analyzer.

The present invention discloses a load-pull slide-screw tuner consisting of a radio-frequency (RF) or microwave slotted airline (slabline) containing a single corrugated RF slug, said corrugated RF slug being controlled horizontally and vertically by remote electric control, allowing the creation of impedances which are distributed over and cover the entire Smith chart, from perfect transparency to high reflection factors. The corrugation structure of the RF slug of this invention provides the slide-screw tuner, with a single RF slug, the same electromagnetic performances than double slugs slide-screw tuner, i.e. same frequency bandwidth of use and equivalent high gamma performances, at a much lower cost of manufacturing.

A calibration procedure for a real-time load-pull system whereby the signal passes through at least one of the tuners of said real-time load-pull system. A calibration standard is connected to the test ports and an electromagnetic wave signal passes through one of the tuners before passing through the wave sensing structure. After having passed the wave sensing structure the electromagnetic wave signal interacts with the calibration element. This results in a reflected and eventually a transmitted electromagnetic wave signal that pass through the wave sensing structures of the system. The sensed electromagnetic wave signals are measured by means of a receiver. The procedure is repeated with different calibration standards. Then a line element is connected to the test ports and, one after the other, a set of calibration standards, a power meter and a harmonic phase reference generator are connected to the output tuner, each time sending a signal and measuring the wave signals. The measured data is used to calculate the error coefficients of the real-time load-pull system.

A hybrid load pull tuner system uses a combination of a passive and active tuner system. A closed loop system means that the system is independent of the available power of the device under test (DUT). The proposed hybrid system is formed around a closed loop Gamma Boosting Unit (GBU) consisting of two back to back broadband directional couplers, broadband variable time-delay, broadband variable phase-shifter and a broadband microwave amplifier, all inserted in the coupled path of the couplers; the GBU is connected in cascade with a passive tuner and boosts its reflection factor; for this the amplifier must have enough linear power and gain to match the difference between the power reflected back to the DUT by the passive tuner and the desired total reflected power to reach the expected Gamma, considering coupling loss and insertion loss of the test fixture.

The invention discloses an RF impedance matching debugging method. The method mainly comprises the steps that data, before optimization, of a signal source are tested; a vector network analyzer performs calibration; the vector network analyzer acquires output impedance of a main board of the signal source through measurement; an impedance matching network value is acquired by using Smith-Chart software in cooperation with load pull data; an impedance matching network is established; the impedance matching network is verified. During RF impedance matching debugging, the impedance matching network value is acquired by using the Smith-Chart software in cooperation with the load pull data; in the debugging process, a computer is used for calculation in cooperation with the Smith-Chart software and the load pull data; in this way, accuracy is guaranteed on the premise that visibility and clearness of physical concepts are guaranteed; meanwhile, the calculation speed is greatly increased, and the defects of a computer simulation method and the defects of a manual calculation method are overcome.

Device characterization performed with a test system including a fixture and multiple frequency dependent test boards. In one embodiment, testing is performed with multiple sets of input and output test boards wherein each set is frequency dependent at different frequencies. In some examples, the test board includes an impedance transformer that is a quarter wave length of the fundamental frequency (f0) of a frequency of which the board is dependent. In some examples, S-parameters and load pull measurements are obtained for the device under test with the test boards at different frequencies.

A fuel cell system determines each of a battery charging current error, a battery voltage error, and a stack current error. The fuel cell system regulates current through a series pass element in response to a greater of the determined errors. Thus, the fuel cell system operates in three modes: battery voltage limiting mode, stack current limiting mode and battery charging current limiting mode. Additionally, there can be a fourth “saturation” mode where the stack voltage VS drops below the battery voltage VB as the load pulls even more current. Individual fuel cell systems can be combined in series and / or parallel to produce a combined fuel cell system having a desired output voltage and current.

A fuel cell system determines each of a battery charging current error, a battery voltage error, and a stack current error. The fuel cell system regulates current through a series pass element in response to a greater of the determined errors. Thus, the fuel cell system operates in three modes: battery voltage limiting mode, stack current limiting mode and battery charging current limiting mode. Additionally, there can be a fourth “saturation” mode where the stack voltage VS drops below the battery voltage VB as the load pulls even more current. Individual fuel cell systems can be combined in series and / or parallel to produce a combined fuel cell system having a desired output voltage and current.

Fast tuning and measuring algorithms in open loop active load pull systems have been developed to accommodate high speed production testing of many chips of the same kind on wafer; they are based on re-setting the (pre-calibrated) amplitude and phase of the injected power into the device output port. Because of the dispersion of the chip characteristics this often leads to non-physical load synthesis, i.e. |Γ|>1, which not only is unrealistic test condition, but also risks destroying the device under test, or reflection factors not high enough to reach the optimum Gamma of the DUT. A method is proposed to use a mechanical tuner in order to shift the active tuning inside meaningful areas; the tuner is also used to pre-match the device to the injection amplifier.

A harmonic load pull system uses a number of synchronized signal sources to inject harmonic power into the output of a power transistor. The mismatch between the signal sources and the transistor internal impedance is reduced by using multi-harmonic tuners, which pre-match the impedance of the signal sources to the internal impedance of the transistor at each harmonic frequency independently. Actual tuning is electronic by changing the amplitude and phase of the injected signals. The transmitted and reflected waves are measured and optimized through bi-directional couplers connected between the transistor and the tuner and a wideband harmonic receiver.

A high speed tuning and measuring algorithm is used for production level testing on-wafer a large number of chips. It applies to a hybrid active injection load pull test system. Using a pre-calibration of the passive tuner and the amplitude and phase settings of the active power injection signal and employing fast harmonic receiver VNA the test system is capable of executing frequency and time domain load pull measurement sets including more than 50 impedance points in a total of 1 second for quantities such as delivered input and output power, PAE, power gain and other. Overall test time, including device hoping and biasing on the automatic probe station is less than 1.5 seconds. This enables production level load pull operations.

The invention discloses a test bench for a prestressed anchor cable anchorage, which comprises a static load hydraulic pump station, a fatigue load loaded power source device, a test bench clamping device, a data detecting instrument and a computer; when the static load hydraulic pump station is started, a pull force is generated to the prestressed anchor cable anchorage by a piston to carry out a static pressure loading test; and when the fatigue load loaded power source device is started, a dynamic pressure is generated by a piston pump to generate a pulsating load with a certain frequency for the piston to carry out a dynamic pressure loading test. The test bench solves the problem of static load pull force and fatigue detection of the anchor cable anchorage and has accurate and visual data through the computation of a computer program, thereby analyzing and predicting the safe service life of the prestressed anchor cable anchorage and performing an important action on effectively reinforcing geotechnical engineering.

The invention discloses an outphasing power amplifier and a method thereof for realizing output matching. The method comprises the following steps: calculating a compensatory angle of a combiner according to a signal power back-off quantity of a signal source; determining a ratio of optimal impedance Zm1 corresponding to a peak output power value of a power tube to optimal impedance Zm2 corresponding to a mean output power value of the power tube according to the compensatory angle obtained by calculation, wherein the ratio is a standing-wave ratio; determining impedance Zopt of a maximum power point of the power tube by a load pulling mode according to the size of an isostatic standing-wave ratio circle; by taking the impedance Zopt of the maximum power point as a reference point, findingout impedance Zbk_eff of a back-off high-efficiency point on the isostatic standing-wave ratio circle; and respectively matching the impedance Zopt of the maximum power point and the impedance Zbk_eff of the back-off high-efficiency point, which are used as corresponding impedance values, to two input ends of the combiner. The method disclosed by the invention ensures that the output power of theoutphasing power amplifier is the maximum and realizes high-efficiency work of the power amplifier; and furthermore, the design complexity is reduced.

The invention provides a device parameter measurement method and device and terminal equipment. The method comprises the steps of obtaining measured data of a to-be-measured device and an error parameter of a load pull measurement system, wherein the measured data is a voltage wave measured by an internal receiver of a vector network analyzer in the load pull measurement system on the basis of theto-be-measured device; and calculating a parameter of the to-be-measured device by utilizing the measured data and the error parameter of the load pull measurement system. Through obtaining the real-time measured data, measured by the vector network analyzer, of the to-be-measured device, the parameter of the to-be-measured device can be calculated in real time without being influenced by the mechanical repeatability of an impedance tuner, so that the measurement accuracy for the parameter of the to-be-measured device is improved.

A mechanically balanced automatic microwave tuner is used in on-wafer device testing. Using low loss rigid airlines to connect the tuner and the devices improves the tuning range at the DUT reference plane but causes mechanical movements of the wafer probes, when the tuner mobile carriage moves horizontally. Balancing the tuner by means of exactly positioned and dimensioned mobile counterweights, driven by the same mechanism as the tuner carriage itself, allows for compensation of the probe movement and safe on wafer operation.

A load pull measurement setup allows independent impedance tuning at RF frequencies at the output of the DUT as well as independent tuning at RF and baseband frequencies of the modulated signal at the input of the DUT. This allows optimizing baseband frequency impedances for nonlinear amplifier performance when processing modulated signal, such as IMD, ACPR etc. Baseband tuning is done using a low frequency programmable impedance tuner, which is connected through the input bias tee, which acts as a frequency separator (diplexer). The input bias tee may be an LC based network or a 3 dB matched coupler based network.

The invention provides a method for acquiring load pull parameters of a radio frequency power amplifier. The method adopts finished products to test, and comprises the following steps: judging whether at least one finished product in N finished products that are configured with the same radio frequency power amplifier belongs to determined high-quality products; if yes, determining a load impedance value of the radio frequency power amplifier of each determined high-quality product by using an impedance parameter system, and measuring the electrical parameters of the radio frequency power amplifier of each determined high-quality product under active conditions by using an electrical parameter system as the load pull parameters of the radio frequency power amplifier; and otherwise, selecting one of the finished products as a finished product to be tested, and changing the matching network parameters of the finished product to be tested to find a set of load pull parameters that meet the use requirements. According to the method provided by the invention, the finished products are adopted to test, a test printed circuit board customized for each DUT is not required, the test cycle can be shortened, resources can be saved, and the additional environmental pollution can be avoided.

The present invention discloses a harmonic reflective tuner system consisting of a radio-frequency (RF) or microwave transmission line having a longitudinal axis, containing two harmonic resonators sliding on the central conductor, where the harmonic resonators are comprising a pair of identical RF slugs, mechanically attached together. The two harmonic resonators will reflect two harmonic frequencies of a base frequency F0. The harmonic reflective tuner of this invention has an input and output, said input being connected to the DUT trough a diplexer in parallel with the fundamental tuner.

A passive slide screw load pull tuner structure can be used on-wafer, in millimeter-wave frequencies from 25 to 110 GHz and above. It uses special tuning probe brackets and a short slabline mounted below the tuner housing, which holds the control gear. The tuner is mounted under an angle matching the angle of the wafer-probe, is connected directly of the wafer-probe and ensures optimum tuning range.

The present invention discloses a harmonic reflective tuner system consisting of a radio-frequency (RF) or microwave transmission line having a longitudinal axis, containing two harmonic resonators sliding on the central conductor, where the harmonic resonators are comprising a pair of identical RF slugs, mechanically attached together. The two harmonic resonators will reflect two harmonic frequencies of a base frequency F0. The harmonic reflective tuner of this invention has an input and output, said input being connected to the DUT trough a diplexer in parallel with the fundamental tuner.