127 results about "Amplifier gain" patented technology

The invention relates to an ultrasonic flow metering device and a metering method thereof, and relates to the field of ultrasonic measuring devices. According to the metering device, through a cross-correlation operation circuit, a microcontroller, a double-threshold comparator, a peak detector, a gain adjustment circuit and a head wave threshold adjustment circuit, self-adaptive processing and adjustment of echo signals and head wave thresholds are achieved, and the accuracy and reliability of flow metering are improved. The metering method adopts an adaptive adjustment strategy of echo signal amplifier gain based on an output signal of an echo signal peak detection circuit, and a head wave threshold adaptive adjustment strategy based on a correlation operation value of echo signal sampling data and pre-stored reference wave data. According to the scheme, the stability of the echo signal and the rationality of the head wave threshold value are guaranteed, the method has adaptability to echo contour feature changes caused by transducer aging or contamination, and then the reliability of the flow metering process is guaranteed.

The invention discloses a low-power-consumption adaptive radio frequency circuit and an adjustment method thereof, the circuit comprises a power control module, a frequency adjustment module and an autonomous adaptive controller, and the power control module is electrically connected with the frequency adjustment module; the power control module is electrically connected with the autonomous adaptive controller, and the power control module is used for monitoring the intensity of an input signal in real time and dynamically adjusting the gain of the radio frequency amplifier; the frequency adjusting module is electrically connected with the autonomous self-adaptive controller, and the frequency adjusting module is used for adjusting the working frequency of the low-power-consumption self-adaptive radio frequency circuit; and the autonomous adaptive controller is used for monitoring real-time data of working environment frequency characteristics of the low-power-consumption adaptive radio frequency circuit and controlling the power control module and the frequency adjustment module based on a monitoring result. Through the mode, parameters can be automatically adjusted according to the real-time environment, the stability of the overall performance of the circuit is improved, and meanwhile power consumption is reduced.

The invention relates to a tunnel reluctance current sensor structure and temperature parameter optimization method and system, and the method comprises the steps: arranging an annular magnetic core, forming symmetrically distributed air gaps in the annular magnetic core, placing a tunnel reluctance current sensor in each air gap, and forming a double-air-gap magnetic circuit structure; constructing a magnetic field consistency coefficient according to the average magnetic induction intensity, the minimum magnetic induction intensity and the maximum magnetic induction intensity of the air gap center area, and performing optimization solution on structural parameters of the double-air-gap magnetic circuit structure by taking minimization of the magnetic field consistency coefficient as a target; respectively establishing a measurement channel and a reference channel according to the double-air-gap magnetic circuit structure obtained through optimization solution; multiple times of voltage signal acquisition are carried out through a reference channel under different injection reference currents and different temperature environments, and a temperature compensation factor is calculated, so that gain parameters of an amplifier in a measurement channel are adjusted. Compared with the prior art, the anti-interference capability and the measurement sensitivity of the system can be greatly improved.

A cascade amplification circuit module based on complementary parameter amplifiers belongs to the technical field of integrated circuit amplifiers and comprises a first-stage complementary parameter amplifier (CPA) and a second-stage amplifier (floating inverting type or transconductance resistance type). The first-stage CPA adopts an NMOS and PMOS complementary structure, passive amplification is achieved through grid multiplexing, a grid capacitor is used for storing signals in the sampling stage, a depletion layer capacitor is switched to improve gain in the amplification stage, common-mode voltage is stabilized through complementary design, and an extra feedback circuit is not needed. And the second-stage amplifier provides driving capability and is combined with passive gain to suppress noise. The cascade structure does not need frequency compensation, the design is simplified, the problem of balancing gain, noise and power consumption of a traditional amplifier is solved, and the cascade amplifier has the advantages of being high in energy efficiency and low in complexity.

Systems and techniques are provided for power amplifier gain error compensation for a Digital Power Amplifier (DPA). In some aspects, a compensation method includes obtaining in-phase (I) and quadrature-phase (Q) components of a baseband sample corresponding to in-phase input amplitude codes and quadrature-phase input amplitude codes. The in-phase input amplitude codes can be distorted based on first gain pre-compensation information corresponding to an in-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the I component. The quadrature-phase input amplitude codes can be distorted based on second gain pre-compensation information corresponding to a quadrature-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the Q component. The DPA can be driven using the pre-distorted output amplitude codes of the I and Q components to generate a Radio Frequency (RF) output.

The invention belongs to the technical field of integrated circuits, and particularly relates to a radio frequency amplifier bandwidth expansion circuit based on resistor-capacitor series feedback. The bandwidth expansion circuit comprises a first-stage common-gate amplifier, a second-stage common-source amplifier, a transformer-based inter-stage matching network between the two stages of amplifiers, and two resistor-capacitor series feedback paths, and a resistor-capacitor series feedback path is bridged at two sides of the interstage matching network, and feedback is introduced from the output end of the common source amplifier to the output end of the common gate amplifier, so that the quality factors of two resonant cavities of the interstage matching transformer are adjusted, and the targets of adjusting the gain of the amplifier and expanding the bandwidth of the radio frequency amplifier are further realized.

Amplifiers with new circuit topologies for gain shaping and gain control are described herein. An example amplifier circuit with gain control includes a differential transistor pair, a main transistor pair coupled to the differential transistor pair, an auxiliary transistor pair coupled to the differential transistor pair, and a resistive impedance coupled between base terminals of the auxiliary transistor pair. The resistive impedance can include a pair of matched resistors coupled between base terminals of the auxiliary transistor pair. The amplifier can also include a capacitor coupled from a virtual ground node between the pair of matched resistors to ground. The amplifier circuits described herein can present a preferred gain response as compared to other amplifiers, at both midband and peaking frequencies. The amplifier circuits also offer additional options for control of gain at midband frequencies, among other benefits.

The embodiment of the invention provides a gain regulation and control precision maintenance method for a programmable Raman amplifier. The method comprises the following steps: acquiring basic scene sample data and target scene sample data to form a source domain sample data set and a target domain sample data set; selecting a proper machine learning method as a basic learning algorithm according to the characteristics of the data in the data set; initializing weights occupied by a source domain sample and a target domain sample; fitting a prediction model by adopting a basic learning algorithm according to the weights of the source domain sample and the target domain sample; re-weighting the source domain sample and the target domain sample according to the total weighting error of the target domain sample so as to correct the difference between the distribution of the source domain sample and the distribution of the target domain sample; and obtaining a model after multiple iterations as a pumping prediction model of the programmable Raman amplifier. When the use scene of the programmable Raman amplifier changes and the accuracy of the regulation and control algorithm of the programmable Raman amplifier is reduced, by means of the method, maintenance of the gain regulation and control precision of the programmable Raman amplifier can be achieved by collecting a small amount of sample data, and the use scene of the programmable Raman amplifier is effectively expanded.

The invention relates to the technical field of wireless communication, and provides a radio frequency power amplifier which comprises a power amplifying circuit, a first biasing circuit, a second biasing circuit and a feedback circuit. The first biasing circuit comprises a first resistor, a first voltage division circuit and a first triode, the first end of the first resistor is used for being connected to an external first power supply, and the second end of the first resistor is connected with the first end of the first voltage division circuit and the base electrode of the first triode; the second biasing circuit comprises a second resistor, a second voltage division circuit and a second triode; the first end of the second resistor is connected with the second end of the first resistor, the second end of the second resistor is connected with the second voltage division circuit and the second triode, and the second triode is connected with the feedback circuit and the power amplification circuit. According to the radio frequency power amplifier, power amplifier gain and linear performance fluctuation caused by temperature change can be reduced, and simplified circuit layout and smaller chip area occupation can be realized.

The invention relates to a reset circuit of a charge sensitive preamplifier. The circuit comprises a trigger signal generation module, a control signal generation module and a reset module, the trigger signal generation module is used for generating a reset trigger signal when the output voltage of the charge sensitive pre-amplifier is increased to the upper threshold voltage or reduced to the lower threshold voltage; the control signal generation module is used for generating a reset control signal according to the reset trigger signal; the reset module is used for generating a reset charge signal in response to the reset control signal and inputting the reset charge signal to the input end of the charge sensitive preamplifier, so that the output voltage is reset to a preset voltage; the reset circuit does not change the working state of the charge sensitive pre-amplifier in the reset process, the problems of gain abrupt change and unstable working state of the amplifier in the reset process are avoided, structures such as a feedback resistor which additionally generates leakage current and noise do not need to be used in the circuit, and the noise performance cannot be deteriorated.

The invention relates to the technical field of electronic circuits, and discloses a coil current feedback control system and method, and the system comprises a signal generator and a power amplifier which are used for supplying power to a target coil; the current acquisition sensor is used for acquiring the real-time current of the target coil; and the processing module is used for comparing the real-time current with a target current of the target coil, and sending a control instruction to the power amplifier when the real-time current is not equal to the target current, so as to adjust the gain of the power amplifier and adjust the real-time current of the target coil to the target current. According to the invention, through real-time measurement and feedback control of the coil current, automatic adjustment of the gain of the power amplifier is realized, and accurate control of the coil current is further realized.

Systems and techniques are provided for power amplifier gain error compensation for a Digital Power Amplifier (DPA). In some aspects, a compensation method includes obtaining in-phase (I) and quadrature-phase (Q) components of a baseband sample corresponding to in-phase input amplitude codes and quadrature-phase input amplitude codes. The in-phase input amplitude codes can be distorted based on first gain pre-compensation information corresponding to an in-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the I component. The quadrature-phase input amplitude codes can be distorted based on second gain pre-compensation information corresponding to a quadrature-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the Q component. The DPA can be driven using the pre-distorted output amplitude codes of the I and Q components to generate a Radio Frequency (RF) output.

The application belongs to the technical field of radio frequency amplifiers, and specifically discloses a CMOS common-source common-gate radio frequency amplifier with temperature and process deviation compensation, which comprises a bias circuit and an amplification stage circuit; the bias circuit adopts a temperature and process deviation compensation bias circuit; when the ambient temperature changes, the bias circuit can collect the real-time temperature of an amplifying tube and generate a new bias voltage, so that the bias state of the amplification stage circuit is dynamically adjusted, and the fluctuation of the gain and power consumption of the amplifier with the temperature change is reduced; similarly, when the process parameter distribution deviation occurs in different regions of a wafer during the chip manufacturing process, the same chip bias circuit and the amplifying tube region of the amplification stage circuit are the same, the same process deviation is generated, the bias circuit can generate a new bias voltage according to the process deviation, the bias state of the amplification stage circuit is dynamically adjusted, and the fluctuation of the gain and power consumption of the amplifier with the process deviation is reduced. The application is suitable for a low-noise amplifier in a WiFi radio frequency front-end module.

This invention belongs to the field of magnetic material measurement technology, and particularly relates to a power amplifier gain control method and system for magnetic characteristic measurement. The method includes the following steps: calculating the instantaneous rate of change of magnetization impedance at each moment, where the instantaneous rate of change of magnetization impedance is positively correlated with the time derivative of the ratio of output voltage to excitation current; calculating the dynamic load margin at each moment, where the dynamic load margin is negatively correlated with the instantaneous rate of change of magnetization impedance and positively correlated with the difference between the power amplifier's supply rail voltage and output voltage amplitude; determining the gain scaling factor at each moment, where the gain scaling factor is positively correlated with the dynamic load margin and its value ranges between a set upper and lower gain limit; and using the gain scaling factor to adjust the drive voltage command in real time to control the power amplifier's output gain, which can effectively improve the accuracy of power amplifier gain control for magnetic characteristic measurement.

The present application proposes a current mirror type gain bootstrap operational transconductance amplifier, comprising: an input circuit receiving a differential input and providing an input transconductance; the current mirror circuit is used for amplifying the gain of the amplifier according to the mirror image proportion; the cascode gain bootstrap circuit is used for improving the output resistance of the current source mirror circuit, so that the gain of the amplifier is further expanded; and the tail current source is connected with the input circuit to provide stable reference current. The amplifier gain can be effectively improved, and the amplifier can be applied to various operational amplifier scenes.

The invention discloses a high-precision multi-band power amplifier gain amplitude-phase calibration device and method based on FPGA control, and the device comprises a numerical control attenuator, a plurality of different segmented phase shifters, a radio frequency multi-way switch, a digital temperature sensing unit, an air cooling system, a power circuit, an FPGA chip, and an upper computer. The numerical control attenuator, the radio frequency multi-way switch and the sectional type phase shifter form a radio frequency calibration link, the numerical control attenuator, the sectional type phase shifter, the radio frequency multi-way switch, the digital temperature sensing unit and the air cooling system are respectively in signal connection with a control output port of the FPGA chip, and the FPGA chip is connected with an upper computer through an RS232 serial port communication circuit. The power supply circuit provides power supply requirements for all the modules, the calibrated power amplifier is connected with the output end of the sectional phase shifter, and the digital temperature sensing unit is attached to the packaging surface of the calibrated power amplifier. According to the invention, the amplitude and phase fluctuation of the power amplifier can be finely controlled within a required range while the signal integrity is ensured, and the problems of low calibration efficiency, low calibration precision and high calibration cost of a traditional calibration device are solved.

The application discloses an optical power collection device and method, relates to the technical field of optical signal detection, and comprises the following: a photoelectric detector for converting an optical signal into a current signal; a transimpedance amplifier for converting the current signal into a pulse voltage signal; a peak detector for detecting the peak value of the pulse voltage signal; an RC filter network for filtering noise of the pulse voltage signal; a low-frequency amplifier for amplifying the low-frequency pulse voltage signal; an ADC collection module for converting the amplified pulse voltage signal into a digital signal; a first feedback network for adjusting the gain of the transimpedance amplifier; a second feedback network for adjusting the gain of the low-frequency amplifier; and a microcontroller for controlling the first feedback network to adjust the gain of the transimpedance amplifier according to the peak value of the pulse voltage signal and for controlling the second feedback network to adjust the gain of the low-frequency amplifier according to the digital signal.

The invention relates to the technical field of radio frequency power amplifiers, and discloses a dynamic calibration control method and system for gain data of a radio frequency power amplifier, and the method comprises the steps: collecting the operation data and impedance real-time change characteristics of the radio frequency power amplifier; mapping the operation data and a preset target output amplitude value to an amplitude temperature gain control strategy of the radio frequency power amplifier to obtain a gain calibration instruction of the radio frequency power amplifier; based on the impedance real-time change characteristics, performing impedance compensation adjustment on the gain calibration instruction to obtain an optimized gain calibration instruction of the radio frequency power amplifier; performing closed-loop feedback control on gain parameters of the radio frequency power amplifier based on the optimized gain calibration instruction to obtain a gain control instruction of the radio frequency power amplifier; based on the gain control instruction, performing control effect evaluation on an output signal of the radio frequency power amplifier to obtain a control deviation index of the radio frequency power amplifier; according to the control deviation index, carrying out adaptive adjustment on an amplitude temperature gain control strategy; according to the invention, the efficiency of dynamic calibration control of the gain data of the radio frequency power amplifier can be improved.

Systems, methods, apparatus, and computer-readable media for power amplifier gain error compensation for a digital power amplifier (DPA) are provided.SOLUTION: A signal compensation method for digitally correcting gain characteristics of a DPA includes obtaining an in-phase (I) component and a quadrature-phase (Q) component of baseband samples corresponding to an in-phase input amplitude code and a quadrature-phase input amplitude code, distorting the in-phase input amplitude code based on first gain predistortion information corresponding to an in-phase signal branch of the DPA to generate an I-component predistorted output amplitude code, distorting the quadrature-phase input amplitude code based on second gain predistortion information corresponding to a quadrature-phase signal branch of the DPA to generate a Q-component predistorted output amplitude code, and the DPA is driven using the I-component and Q-component predistorted output amplitude codes to generate a radio frequency (RF) output.SELECTED DRAWING: Figure 17

The invention discloses a variable gain amplification unit and a dual-mode variable gain amplifier, and relates to the technical field of radio frequency integrated circuits. The variable gain amplifier aims to solve the problem that an existing variable gain amplifier cannot meet existing control requirements. According to the variable gain amplification unit and the dual-mode variable gain amplifier, the reconstruction of the gain change range can be realized by adjusting the bias voltage and the number of the cascaded VGA arrays, and different design requirements are met; in the VGA mode, the gain of the amplifier is controlled by the analog voltage and is continuously adjustable in the gain change range. In the PGA mode, the gain of the amplifier is controlled by a digital signal, and the linearity of gain change is extremely high. The circuit is built based on the VGA units with simple structures, and has the advantages of being easy to implement and low in power consumption.

The invention discloses an O-band Raman amplifier gain optimization design method based on a tree species optimization algorithm. The method comprises the following steps: randomly selecting a plurality of groups of pumping parameters as initial tree species; calculating a Raman amplifier gain value of the initial tree species, taking the Raman amplifier gain value as a fitness value of an optimization algorithm, and performing gain adjustment on the initial tree species to obtain dominant tree species; randomly generating multiple groups of first tree species and second tree species near the dominant tree species, and combining the first tree species and the second tree species as second-generation tree species; calculating a second-generation fitness value of the second-generation tree species, and performing iterative optimization on the second-generation fitness value for a plurality of times according to the steps to obtain an optimal fitness value; and outputting the corresponding optimal tree species according to the optimal fitness value. According to the invention, the problem of multi-objective optimization of pumping parameters is solved, and the transmission distance of O-band signals is effectively improved.

The present disclosure provides an electromagnetic compatibility method and device based on power amplifier sound effect dynamic adjustment and electronic equipment, which can realize sound effect dynamic adjustment of a vehicle-mounted power amplifier system based on a backhaul signal, reduce electromagnetic interference risk among a backhaul link, a high-speed digital link and a power amplifier output link from a design source, improve the purity of the backhaul signal and the accuracy of sound effect mode recognition, reduce the risk of EMC exceeding caused by changes in power amplifier gain or clock radiation during dynamic adjustment, and thus improve the working stability, reliability and efficiency of passing vehicle-grade electromagnetic compatibility test of the vehicle-mounted power amplifier system in a complex electromagnetic environment.

The invention discloses a modulation grating Y-branch broadband tuning external cavity laser and equipment. The modulation grating Y-branch broadband tuning external cavity laser comprises a semiconductor optical amplifier (SOA) gain chip area; an outer cavity waveguide region; the semiconductor optical amplifier SOA gain chip area and the outer cavity waveguide area are in coupling connection through the coupling module, and the outer cavity waveguide area comprises a waveguide structure; the Y-branch sampling grating structure is arranged on the surface of the waveguide structure, the Y-branch sampling grating structure is provided with a first sampling grating and a second sampling grating, a chalcogenide phase change material layer is arranged on the surface of the first sampling grating or the second sampling grating, and the chalcogenide phase change material layer comprises a plane part and a convex part which are connected with each other; and the convex part is filled in the groove of the first sampling grating or the second sampling grating. Therefore, rapid and accurate multi-stage wavelength tuning of the external cavity laser can be realized in an extremely short time, and meanwhile, the power consumption of the external cavity laser is effectively reduced.

The invention discloses a fully differential current domain echo cancellation analog front-end circuit and a working method thereof. The circuit comprises a resistor R50toAVDD, a resistor Rhybrid and a local sending current source LS, one end of the resistor R50toAVDD is connected with a chip pin, the other end of the resistor Rhybrid is connected with a power supply positive electrode VDD, the other end of the resistor Rhybrid is connected with one end of an echo cancellation current source LScancel, one end of a fixed pull-down current source Idc and one end of a capacitor ACcoupled, the other end of the capacitor ACcoupled is connected with a recovery resistor Rdc and a gain amplifier Gain, and the other end of the recovery resistor Rdc is connected with a power supply positive electrode VDD. And the resistor Rhybrid and the capacitor ACcoupled are respectively connected in parallel with a signal switch. The method supports three working modes, can adapt to application requirements of different coding modes and different rates, and simplifies BOM management.

The invention provides a DC-DC converter based on ripple control. The DC-DC converter comprises an output circuit, a ripple voltage generation circuit, a PWM logic circuit, a fixed conduction time control circuit, a driving circuit and a ripple compensation circuit. Wherein the ripple compensation circuit can calculate the amplitude of the ripple and generate two paths of current in direct proportion to the amplitude of the ripple, the current enters the loop to respectively adjust the gain of the amplifier in the voltage loop and the gain of the amplifier in the ripple loop, and when the amplitude of the ripple becomes large, the gain of the amplifier in the voltage loop becomes large, and the gain of the amplifier in the ripple loop becomes small. When the ripple amplitude becomes small, the gain of the amplifier in the voltage loop becomes small, and the gain of the amplifier in the ripple loop becomes large. Changes in gain of the amplifiers in the voltage loop and the ripple loop can adjust changes in ripple amplitude. Therefore, the amplitude of the equivalent ripples entering the loop is relatively stable, so that the stability of the converter is optimized. And meanwhile, the transient response and the Jitter effect can be improved due to the relatively stable ripple amplitude.

An integrated circuit and a PLL circuit including the same are provided. An integrated circuit receiving a control voltage and converting the control voltage into an oscillator control current includes a PAR circuit outputting a compensation current compensating for at least one of process variation, power voltage variation, and temperature variation of the integrated circuit, an amplifier including a first power terminal receiving a power voltage, a second power terminal outputting an amplifier current determining a gain of the amplifier, an inverting input terminal receiving the control voltage, and a non-inverting input terminal receiving an amplifier voltage formed based on the gain of the amplifier, and an IDAC circuit converting a reference current generated based on the amplifier voltage into the oscillator control current according to an IDAC code. The PAR circuit outputs the compensation current.

An adaptive gain transient electromagnetic receiving system based on exponential prediction and a method thereof are provided. The system includes a signal input unit, an amplification unit, a gain control unit, and a dual channel signal acquisition card. The signal input unit includes a receiving coil and a low-pass filter, and the amplification unit is a voltage controlled amplifier; the low-pass filter pre-processes the output signal of the receiving coil and divides the output signal into two signals. One is passed through a gain control unit, and the other enters into a voltage controlled amplifier. The A / D converter of the gain control unit converts the analog signal output by the low-pass filter into a digital signal, the FPGA module calculates the gain voltage, and the dual channel signal acquisition card collects the amplified signal and gain voltage simultaneously, which enhances the signal detection capability in deep regions.

A high-precision integrated temperature sensor circuit and a temperature sensor relate to the technical field of integrated circuits, and comprise a band-gap reference circuit, a buffer circuit, an analog-to-digital conversion circuit, a two-phase non-overlapping clock generation circuit and an FIR digital filter. It needs to be explained that a key circuit sigma-delta modulator adopts an integrator cascade feed-forward structure CIFF, compared with a CIFB with a feedback structure, an STF function of an ADC of a feed-forward structure is close to 1, a peak value can appear only at a high frequency, only a very small error signal can pass through a whole loop, and therefore the stability of the analog-to-digital converter is greatly improved. Therefore, the gain of the amplifier in the first-stage integrator can be made relatively large, and noise and nonlinearity generated by the rear-stage integrator are effectively suppressed. Moreover, each stage of integrator does not process a feedback signal with high-frequency noise, so that the bandwidth requirement on the next stage of operational amplifier is reduced, the power consumption required by the CIFF structure is lower, and meanwhile, the output swing has better stability due to no feedback structure.

A system for calibrating signals received through a power line within a vehicle includes a signal conditioning circuit that converts analog input signals into digital input signals. In one configuration, the circuit includes an adjustable gain circuit that outputs an amplifier gain signal, establishing an amplifier gain level, and an amplifier that outputs amplified signals in response to the analog input signals and the amplifier gain signal. In another configuration, the circuit includes a bias circuit that outputs a bias signal, establishing a bias level, and a comparator that generates the digital input signals in response to the analog input signals and the bias signal.A controller receives the digital input signals and generates, depending on the mode, one or more control signals configured to control the amplifier gain signal setting and amplifier gain level and / or the bias signal and bias level.

Certain aspects of the present disclosure generally relate to electronic circuits and, more particularly, to techniques and apparatus for signal amplification. One example method for signal amplification generally includes detecting an over-current condition associated with an amplifier and adjusting an amplification gain to an adjusted gain level for an input signal based on the over-current condition. The amplification gain may be maintained at the adjusted gain level until occurrence of an amplifier gain event. The method may also include amplifying, via the amplifier, the input signal based on the adjusted amplification gain.