81 results about "Linear amplification" patented technology

The invention relates to the technical field of weak signal conditioning circuits, and discloses a multi-light-source spurious noise suppression circuit based on a laser sensor and a signal conditioning method, and the circuit comprises a photoelectric conversion module which is used for converting a received optical signal into a current signal; the transimpedance conversion module is connected with the photoelectric conversion module, converts the current signal into a first voltage signal and suppresses common-mode noise; the first-stage amplification module is used for carrying out linear amplification on the first voltage signal and outputting a second voltage signal; the programmable filtering module is used for carrying out high-frequency noise suppression on the second voltage signal; the reverse phase adjusting module is used for adjusting the phase and the amplitude of the filtered signal so as to adapt to a post-stage load; and the feedback control module analyzes the frequency spectrum of the output signal in real time and dynamically adjusts the cut-off frequency of the programmable filtering module. The invention aims to solve the problems that in the prior art, a laser sensor circuit is poor in anti-interference performance in a multi-light-source environment, and measurement is inaccurate due to spurious noise.

The invention discloses a current measuring circuit based on a quadrupole mass spectrometer, and the circuit comprises an input module which is used for receiving a current signal from the quadrupole mass spectrometer; the current detection module is used for carrying out current measurement on the current signal; wherein the current measurement module comprises a positive current measurement unit and a negative current measurement unit, the positive current measurement unit is used for measuring the positive current of the quadrupole mass spectrometer, and the negative current measurement unit is used for measuring the negative current of the quadrupole mass spectrometer; according to the current measurement circuit, small current linear amplification and large current logarithmic amplification are realized through the current measurement module, so that a high-range measurement effect is achieved, fA level-uA level current measurement can be realized, and meanwhile, automatic range switching is realized through circuit characteristics; and the cost is about one fiftieth of that of a reed switch range switching scheme.

The invention relates to a differential voltage time-digital converter for preventing large based on Double-tailed, and the differential voltage time-digital converter comprises a Double-tailed dynamic latch comparator which carries out the linear amplification of an input differential voltage, and outputs a differential voltage; a voltage time domain converter (VTC) which converts the output differential voltage into a time difference signal and outputs a first delay voltage and a second delay voltage; the input end of the polarity judging device is connected with the VTC, and the polarity judging device is used for outputting a polar code as the highest bit of a thermometer code; the input end of the edge selector ELS is connected with the VTC, and the edge selector ELS is used for generating an EARLY signal and a LATE signal according to the first delay voltage and the second delay voltage; and the input end of the delay chain type time-to-digital domain converter TDC is connected with the edge selector ELS, and the delay chain type time-to-digital domain converter TDC is used for quantizing the time difference between the EARLY signal and the LATE signal and generating a thermometer code. According to the invention, the idea of high-speed latch is introduced to obtain stable differential input voltage with smooth waveform, so that the VTC module can carry out time domain transformation on the differential input voltage, and the resolution of the TDC is improved.

The invention discloses a device for inhibiting grating lobes of an acoustic transducer array by using band-pass driving signals, which comprises an upper computer, an acoustic host and an acoustic transducer array which are connected in sequence, the acoustic host comprises a logic control circuit, N direct digital synthesis circuits connected with the logic control circuit, and N linear amplification circuits connected with the N direct digital synthesis circuits in a one-to-one correspondence manner, so that N channels are formed; and the acoustic transducer array is a linear regular arrangement array and comprises N transducer array elements connected with the N linear amplification circuits in a one-to-one correspondence manner, the width of each transducer array element is L, the spacing distance between the adjacent transducer array elements is dL, the resonance center frequency of each transducer array element is F, and the relative bandwidth is B. According to the invention, a good grating lobe suppression effect can be obtained with relatively low technical cost.

The invention relates to the technical field of road safety facilities, in particular to a gradient effect concave deceleration strip visual grading mark design method which comprises the steps that S1, basic design data of a target road scene are obtained, and the basic design data comprise a target limited vehicle speed numerical value and a total length numerical value of a deceleration area; s2, according to the basic design data, geometric configuration parameters of a plurality of concave speed reduction units sequentially arranged in the vehicle advancing direction are calculated, and the geometric configuration parameters comprise the concave depth numerical value of each concave speed reduction unit and the distance numerical value between every two adjacent concave speed reduction units; the concave depth value obtained through calculation presents a gradually increasing trend in the vehicle advancing direction. According to the method, the concave speed reduction units with the gradually-increased depth and the gradually-decreased interval are configured through an algorithm, the overspeed vehicle is forced to decelerate through non-linear amplified composite vibration, and the control efficiency of road section speed limiting is improved.

The application is suitable for the biotechnology field, and provides a multiplex amplification method and system and application, wherein the multiplex amplification method comprises the following steps: linear amplification of a target template by using an upstream primer mixture designed for multiple target regions to obtain a first product by purification; the 5' end of the upstream primer contains a universal primer sequence, and the 3' end contains a specific target recognition sequence; linear amplification of the first product by using a downstream primer mixture designed for multiple target regions to obtain a second product by purification; the 5' end of the downstream primer contains a universal primer sequence, and the 3' end contains a specific target recognition sequence; and unified exponential amplification of the second product by using a universal primer. The application innovatively adopts a specific multi-target molecular marker combined with a universal primer amplification strategy to establish a brand-new multi-target DNA fragment amplification technology system, and high uniformity, high specificity and high-throughput multi-target amplification can be realized.

The invention discloses a vibration wire sensor health state diagnosis device and method, and relates to the technical field of sensor state diagnosis, the device comprises a main processor, a vibration signal generation module, a linear amplification circuit and a saturation amplification circuit, the vibration signal generation module generates an excitation modulation signal so as to enable a vibration wire of a vibration wire sensor to vibrate, and the linear amplification circuit is connected with the saturation amplification circuit; a vibrating wire vibration signal of the vibrating wire sensor is collected through the signal processing unit, a linear amplification signal and a multiple harmonic signal are obtained through the linear amplification circuit and the saturation amplification circuit, and the main processor carries out time domain and frequency domain signal processing on the linear amplification signal and the multiple harmonic signal. And obtaining a signal-to-noise ratio value and the duration time of each harmonic signal, and judging and diagnosing the health state of the vibrating wire sensor according to the time domain and frequency domain signals in the linear amplification signal and the multiple harmonic signals, the signal-to-noise ratio value and the duration time of each harmonic signal, so that automatic diagnosis of the health state of the vibrating wire sensor is realized.

An imaging method of a coherent Raman scattering imaging device based on spectral progressive scanning according to the present invention includes a synchronous two-color light source, a nonlinear amplification and spectral broadening module, a spectral progressive scanning control module, a linear amplification module, a beam combining and sample detection module, and a data processing module. The present invention does not require tuning a laser oscillator, nor does it require time scanning. By controlling the seed light and pump light of the nonlinear amplifier, adjusting parameters such as the dispersion, power, chirp of the seed light, and the pump power of the amplifier, the spectral evolution of the nonlinear amplifier is dynamically adjusted, so that it gradually transitions from a narrow spectrum to a wide spectrum, and from covering a single Raman peak to progressively covering multiple Raman peaks. This spectral progressive scanning coherent Raman light source can achieve simultaneous imaging of multiple chemical bonds, has a fast scanning speed, a flexible imaging method, and combines high spectral resolution and a wideband detection range, and also provides a new way to eliminate noise in coherent Raman scattering imaging.

The invention is applicable to the technical field of biology, and provides a multiple amplification method and system and application wherein the multiple amplification method comprises the following steps: performing linear amplification and purification on a target template by using an upstream primer mixture designed for a plurality of target regions to obtain a first product; the 5'end of the upstream primer contains a universal primer sequence, and the 3 'end of the upstream primer contains a specific target recognition sequence; performing linear amplification on the first product by using a downstream primer mixture designed for a plurality of target areas, and purifying to obtain a second product; the 5'end of the downstream primer contains a universal primer sequence, and the 3 'end of the downstream primer contains a specific target recognition sequence; and performing uniform exponential amplification on the second product by using a universal primer. According to the invention, a brand new multi-target DNA fragment amplification technology system is established by innovatively adopting a specific multi-target molecular marker and combining a universal primer amplification strategy, and high-uniformity, high-specificity and high-throughput multi-target amplification can be realized.

The invention discloses an ultrasonic flow measuring device based on a transfer function waveform optimizer, and belongs to the technical field of ultrasonic flow measurement. The problem that the flow measurement precision of an existing ultrasonic flow measurement device needs to be improved is solved. The ultrasonic flow measuring device comprises a transmitting transducer, a receiving transducer, a waveform optimizer and a linear amplification excitation module. The waveform optimizer optimizes an excitation waveform and outputs an excitation signal through the waveform generator, and is used for enabling the output signal of the receiving transducer to present a stable sine section and / or a high signal-to-noise ratio section; and the linear amplification excitation module performs linear amplification excitation on the output signal of the waveform generator, so that the transmitting transducer can reproduce the excitation signal output by the waveform generator.

The invention relates to an array type monitoring device for a loose part of a nuclear power station. The array type monitoring device comprises a channel selection array module and a channel switching array module which are integrated in a processor. The channel selection array screens target signals from multiple sound channels and playback channels through a preset logic (based on signal intensity and key areas), and supports single-channel extraction or multi-channel fusion; the channel switching array realizes smooth interference-free switching between real-time signals and between real-time and historical playback signals based on a special algorithm. The device adopts a 2U rack type design and is internally provided with a dual-power-amplifier system; a D-type power amplifier drives left and right sound channel loudspeakers by a high-frequency switch technology, and the power consumption is less than or equal to 75W; the class AB power amplifier drives an earphone interface through linear amplification, and the distortion rate is lt; 6%. And the integrated storage module supports historical sound data backtracking analysis. The problems that existing equipment is insufficient in multi-channel processing, inflexible in switching and poor in power amplifier adaptability are solved, and the comprehensiveness, timeliness and accuracy of nuclear power station loose part monitoring are comprehensively improved.

The invention relates to the technical field of discrete manufacturing industry production process control, and discloses an automatic collaborative regulation system for a discrete manufacturing industry production process, which comprises a node control unit distributed at a process node and a collaborative control resolving unit, the cooperative control calculation unit converts the node operation rhythm into a time axis distribution parameter in a sequential logic correlation model, calculates a target adjustment vector based on the parameter, and superposes a compensation pulse at the output leading edge of the target adjustment vector by using a feed-forward shaping mechanism, so that an adjustment signal breaks through a physical execution dead zone of a bottom-layer driving execution unit, and the control of the bottom-layer driving execution unit is realized. According to the method, through signal shaping and smoothing of the dynamic impedance difference between the ideal control law and the mechanical actuator, the non-lagging response to extremely fine disturbance is realized, the non-linear amplification of errors in a rigid time sequence frame is blocked, and the stable convergence of a control loop is ensured.

The invention discloses a temperature control circuit of an oven controlled crystal oscillator, which is characterized in that on the basis of a traditional thermosensitive bridge and a heating circuit, a switch driving mode of a driving circuit is changed into a linear mode, namely a linear voltage comparison circuit is added, and the linear voltage comparison circuit not only has a linear amplification function, but also has a PID (Proportion Integration Differentiation) calculation function. In addition, the heating circuit is connected with the voltage-controlled current source circuit. When the thermosensitive bridge is unbalanced, the thermosensitive bridge generates a voltage signal difference related to the temperature, the voltage difference drives a heating power tube of the heating circuit after being subjected to linear amplification and PID calculation through the linear voltage comparison circuit, and when the set temperature is reached, the thermosensitive bridge and the linear voltage comparison circuit output constant voltage. The heating circuit generates constant heating power, and the whole circuit reaches a balanced state. According to the invention, after the voltage difference is regulated and controlled through the linear comparison circuit, the heating power tube is controlled, and the control is not an on state or an off state, but is related to the amplitude of the voltage difference, so that the temperature control precision is improved, and under the cooperation of the PID circuit, the temperature overshoot phenomenon is well inhibited.

The invention belongs to the technical field of power supply circuits, and particularly relates to a four-quadrant direct-current linear adjustable power supply device and a working method thereof.The four-quadrant direct-current linear adjustable power supply device comprises a linear amplification circuit, a positive power supply selection circuit, a positive power supply adjustment circuit, a negative power supply selection circuit, a negative power supply adjustment circuit and an output stage circuit; an input signal is amplified to the output stage circuit through the linear amplification circuit, so that the positive power supply selection circuit outputs a corresponding adjustable positive voltage to a load through the positive power supply adjustment circuit and the output stage circuit, or the input signal is amplified to the output stage circuit through the linear amplification circuit; the negative power supply selection circuit outputs a corresponding adjustable negative voltage to a load through the negative power supply adjustment circuit and the output stage circuit; adjustable input positive voltage and input negative voltage can be obtained, meanwhile, the linear amplification circuit is matched with the output stage circuit to achieve linear continuous adjustable output within the range of + / -210V, and the wide-range, high-precision and four-quadrant working capacity is achieved.

The present invention discloses a peak voltage detection circuit and a peak voltage detection method. The circuit includes: NMOS transistor M1, NMOS transistor M2, NMOS transistor M6, PMOS transistor M3, PMOS transistor M4, PMOS transistor M7, and PMOS transistor M8, a tail current source I1, a pull-down current source I2, and a sample-and-hold capacitor Ch. Among them, the NMOS transistors M1 and M2 form a differential input transistor pair. The gate of the PMOS transistor M3 is connected to the gate of the PMOS transistor M4, and the gate of the PMOS transistor M7 is connected to the gate of the PMOS transistor M8. A switch S5 is also connected between the drain of the PMOS transistor M3 and the source of the PMOS transistor M4. The circuit in the present invention can collect and hold the peak voltage of the echo pulse with linear amplification for a certain period of time for gray-scale measurement, thereby reducing the requirement for the speed of the ADC. Moreover, it can reduce the measurement error caused by circuit offset and achieve accurate measurement.

The invention relates to the technical field of lasers, and discloses a self-starting 9-shaped cavity optical fiber laser with an adjustable feedback loop and a using method, the self-starting 9-shaped cavity optical fiber laser comprises a non-linear amplification annular mirror and a linear arm, and a third coupler is arranged between the non-linear amplification annular mirror and the linear arm; the nonlinear amplification loop mirror comprises a gain optical fiber, a polarization-maintaining wavelength division multiplexer and a phase shifter, the gain optical fiber, the polarization-maintaining wavelength division multiplexer and the phase shifter are sequentially connected in a closed mode, and the polarization-maintaining wavelength division multiplexer is connected with the pumping source; the feedback unit is arranged on the nonlinear amplification loop mirror, the two ends of the feedback unit are communicated with the gain optical fiber and the polarization-maintaining wavelength division multiplexer respectively, and light output by the rear end of the gain optical fiber is fed back to the gain optical fiber through the feedback unit to form a feedback loop. By constructing a closed-loop feedback loop, the noise energy in the cavity is enhanced, the mode locking threshold and the starting time are reduced, the gain fiber amplification gain is dynamically adjusted, the nonlinear phase shift accumulation is stably controlled, an external complex system is avoided, and the all-fiber low-cost efficient design is realized.

The invention discloses a precise construction strategy of a high-sensitivity DNA circulation inducible fluorescent nanorobot, which specifically comprises the following steps: A1, constructing a DNA nanostructure framework which is composed of a modularly designed recognition domain, a signal conversion domain and a circulation trigger domain, the recognition domain comprises an aptamer or a hairpin structure and is used for specifically combining with a target molecule, and the circulation trigger domain is used for specifically combining with the target molecule; the invention relates to the technical field of gene engineering. According to the precise construction strategy for the high-sensitivity DNA circulating inducible fluorescent nano-robot, through integration of a modular DNA tetrahedral framework and an enzyme digestion-strand displacement synergistic amplification system, cyclic utilization and signal exponential gain (such as CHA cascade amplification combined with CRISPR-Cas12a trans-cleavage) of a target object are achieved, the detection limit breaks through the 0.1 am level, and the accuracy of the high-sensitivity DNA circulating inducible fluorescent nano-robot is greatly improved, so that the accuracy of the high-sensitivity DNA circulating inducible fluorescent nano-robot is improved, and the accuracy of the high-sensitivity DNA circulating inducible fluorescent nano-robot is improved. Compared with a traditional single enzyme digestion or linear amplification method, the sensitivity is improved by at least three orders of magnitude. Meanwhile, time-resolved upconversion nanoparticles (UCNPs) are combined with a magnetic bead separation-lock type probe noise reduction technology.

The application provides a photochemical reactor, method and system with total reflection characteristics, and relates to the technical field of photochemistry.The application aligns a light source with the direction of a reaction fluid, and uses total reflection conditions to constrain light energy in a reaction system, thereby forming an orderly propagating optical waveguide structure, and fundamentally solving the problem of serious loss caused by disordered scattering of light energy, wall absorption and transmission in the prior art.Orderly and efficient use of light energy enables faster reaction rate under the same light intensity, or higher light intensity can be used under small pipe diameter, thereby greatly improving reaction efficiency and shortening reaction time.The reactor structure of the application is only a simple pipe structure, and does not need complex optical fiber coupling or nested channels, and linear amplification can be realized through simple series connection or parallel connection without obvious adverse amplification effect.Two total reflection modes can be flexibly selected to adapt to reaction systems with different refractive indexes, are widely applicable, and have simple structure and low energy consumption, and meet the requirements of green chemistry.

This invention discloses a method for magnifying minute motion in reconstructed image sequences based on event streams, solving the problem of blurred minute motion details in poorly reconstructed images, belonging to the field of computer vision. The method includes: converting the original event stream data of the target in the task into a grayscale image sequence; performing a Fourier transform to obtain a frequency domain sub-band set; introducing a complex controllable pyramid algorithm to obtain a feature sub-band set with multi-scale and multi-directional joint characteristics, separating phase component sets and amplitude component sets; performing S-transform time-frequency filtering on the separated phase component set to obtain a phase component set in the time-frequency domain, and obtaining an enhanced phase component set based on a linear amplification factor; fusing the enhanced phase component set and the separated amplitude component set sub-band by sub-band to obtain a reconstructed frequency domain sub-band set, and outputting a magnified minute motion image sequence after Fourier inverse transformation to the time domain. This invention achieves accurate extraction of motion information from poorly reconstructed images.

The invention relates to the field of motor control, and provides a method and a device for preventing an electronic switch from working in a linear amplification region in order to prevent the electronic switch from working in the linear amplification region. The turn-off control unit outputs a control signal to the drive control unit, so that the electronic switch stops working immediately, and the electronic switch is prevented from working in a linear amplification region to cause device failure.

The utility model relates to a novel three-phase voltage isolation detection circuit, which comprises a three-phase rectification network, a voltage division network, an isolation and linear amplification unit and a differential amplification unit, one end of the three-phase rectification network is connected with an AC three-phase power supply; the other end of the three-phase rectification network is connected with one end of the voltage division network; the other end of the voltage division network is connected with one end of the isolation and linear amplification unit; and the other end of the isolation and linear amplification unit is connected with the differential amplification unit. According to the novel three-phase voltage isolation detection circuit, voltage waveform detection and calculation can be carried out on three-phase alternating current at the same time through an ingenious current structure without using a voltage sensor, the three-phase alternating current is converted into an analog-digital signal which can be directly recognized and used by a processor, and the novel three-phase voltage isolation detection circuit has the advantages of being small in size, low in cost, high in reliability and the like. And the system can be widely applied to various industrial control and related electric control fields, and has objective practicability and economic characteristics.

The invention provides a tea quality grading system and method based on image detection, and relates to the technical field of image processing. Dynamic modulation is implemented in a feature extraction stage; linear amplification of a morphological enhancement coefficient and exponential attenuation of a texture sensitive coefficient are performed on a spatial feature reference coefficient set for uneven illumination, and contour distortion under shadow highlight interference is suppressed; directional compensation is performed on a spectral feature reference coefficient for color temperature offset, and features are extracted in a Lab color space in different channels based on tea form types, so that false detection caused by heterogeneous tea feature interference is avoided; in the decision-making stage, three-order collaborative optimization is achieved through an environment adaptation decision-making matrix, core features are dynamically screened through a feature weight matrix to improve the robustness of the model, a dynamic threshold value is generated through fusion of classification threshold value vectors and feature discrete features, confidence weighted correction is executed through level weight vectors, and finally the classification accuracy is guaranteed.

The application belongs to the technical field of quantum communication, and in particular relates to a polarization-frequency two-degree-of-freedom encoding coherent state noiseless linear amplification method. The parallel amplification idea is used. The original polarization-frequency two-degree-of-freedom encoded coherent state is split into N paths through a beam splitter array. The coherent state in each path becomes a weak coherent state. A PC amplifier and an auxiliary photon are arranged on each path. The photon state of each path is amplified. If all the PC amplifiers on all the paths operate successfully, the output states of all the amplifiers are converged on a path through another beam splitter array. Finally, a new coherent state is extracted. The application can effectively improve the average photon number in the output coherent state, realize amplification of the coherent state, and perfectly preserve the information of the photon encoding in the polarization and frequency two degrees of freedom. In addition, the application has strong practicability.

The invention provides a double-closed-loop optical accelerometer. The double-closed-loop optical accelerometer comprises a sensing head and a signal processing unit, the signal processing unit comprises a laser LD, a first photoelectric detector, a second photoelectric detector, a trans-impedance amplifier, an A / D conversion circuit, a lock-in amplifier, an FPGA, a cantilever beam phase locking controller, a light source power locking controller, a D / A conversion circuit, a linear amplification circuit and a constant current source circuit. The FPGA is used for generating two sinusoidal signals with the same frequency; on the basis that the cantilever beam is stabilized at a closed-loop working point through electromagnetic force driving, phase locking of the cantilever beam is realized through superposition of electromagnetic force modulation, so that the 1 / f noise of the system is reduced, and the influence of stray light interference is eliminated; in addition, closed-loop locking is carried out on the output power of the light source, and low-frequency fluctuation noise and relative intensity noise caused by light power drifting are reduced. The light emitting power of the light source is locked, and the detection precision of the whole optical acceleration is improved.

The utility model discloses a current amplifier with a pA-mA range, which relates to the technical field of nuclear power secondary instruments and comprises an input circuit, a current-voltage conversion circuit, a range control circuit, a compensation circuit, a voltage reverse circuit and a voltage isolation output linear amplification circuit. The input end of the current-voltage conversion circuit is respectively connected with the output end of the input circuit, one end of the range control circuit and the compensation circuit; the output end of the current-voltage conversion circuit is respectively connected with the input end of the voltage reverse circuit and the other end of the range control circuit; the output end of the voltage reverse circuit is connected with the input end of the voltage isolation output linear amplification circuit; and the output end of the voltage isolation output linear amplification circuit is used as the output end of the current amplifier. The accuracy and range of current measurement can be effectively improved, the structure is simple, and the cost of the current amplifier can be effectively reduced.

A method for amplifying a DNA target region is provided. The method includes: linearly amplifying a fragmented DNA including the target region by a specific primer to provide a linear amplification product, where 3′ end of the specific primer is modified by a duality functional group, a phosphodiester bond of a part of nucleotide backbone at the 3′ end of the specific primer is modified by phosphorothioate, and the duality functional group is used to prevent the 3′ end of the specific primer from ligation with other oligonucleotides and can be removed by a specific enzyme to perform a linear amplification of the specific primer. The method for amplifying a DNA target region effectively reduces a non-specific amplification during the linear amplification by introducing a phosphorothioate modification into the specific primer.

The embodiment of the invention discloses a wide-range pre-amplification circuit with a temperature compensation function and photoelectric detection equipment. The wide-range pre-amplification circuit comprises a cross-group amplification module, a filtering module and a logarithmic amplification module which are connected in sequence; for a weak light current signal in a large dynamic range, a transimpedance amplification module is designed by using an operational amplifier to carry out I / V conversion circuit, so that signal distortion caused by parasitic capacitance and gain resistance of a photoelectric conversion device is avoided; a logarithmic amplification module and a temperature compensation module designed by using a cut-off and amplification region of a triode are used for performing piecewise linear amplification on a voltage signal output by a transimpedance amplification module, high gain is used for amplifying when a small signal is input, and low gain is used for amplifying when a large signal is input so as to meet the input range of a high-precision ADC; the problem of high-precision measurement of wide-range weak signals is solved, and the temperature stability of the double-slope logarithmic amplification circuit is improved by utilizing the temperature compensation module.

The application provides an envelope tracking method and device, the method obtains a target envelope tracking input current signal through a boost circuit, and transmits the target envelope tracking input current signal to an amplification circuit through the boost circuit; the amplification circuit comprises an operational amplifier and a feedback network, and the operational amplifier works in a floating ground mode; the amplification circuit performs closed-loop conversion amplification on the target envelope tracking input current signal, and outputs an envelope tracking output voltage; the application also provides an envelope tracking device, and solves the problem that in the prior art, when the envelope tracking output voltage amplitude is high and the swing is large, the operational amplifier has high loss and low efficiency in the linear amplification process, so that the target envelope tracking input current signal is converted and amplified more efficiently, the conversion efficiency of the operational amplifier is improved, the amplification loss is reduced, and the user experience is improved.

The application relates to an anti-interference AGC baseband communication device based on a burst OFDM waveform, which comprises a radio frequency front-end circuit, a radio frequency receiving circuit and a baseband processor; the radio frequency front-end circuit is used for receiving and amplifying and filtering a signal and then transmitting the signal to the radio frequency receiving circuit; the radio frequency receiving circuit amplifies, mixes and digitizes an input signal and then transmits the signal to the baseband processor; the baseband processor is used for calculating the RSSI and the air interface power value of each period, determining the gain adjustment mode according to the air interface power value; when the gain adjustment mode is AGC adjustment, the RSSI is adjusted to a linear amplification area, and the total gain needing to be adjusted is obtained by subtracting a target gain value; the gain gear value of the amplifier in the radio frequency front-end circuit needing to be turned on is calculated according to the total gain needing to be adjusted and is then sent to the radio frequency front-end circuit; and the gain code word of the radio frequency receiving circuit needing to be adjusted is calculated in the linear adjustment area and is then sent to the radio frequency receiving circuit.

The invention discloses a miRNA detection kit and method based on Cas12a self-circulation and CHA double cascade amplification, and belongs to the technical field of biosensing. The method comprises the following steps: firstly, converting target miRNA into a double-stranded DNA activator by utilizing self-assembly of a catalytic hairpin; furthermore, a CRISPR-Cas12a positive feedback self-circulation system based on specially designed scgRNA is triggered, so that exponential amplification of a signal is realized; finally, the Au-coated CuO core-shell nano-enzyme with high catalytic activity is released by cutting a connecting chain, and TMB-HO chromogenic reaction is catalyzed, so that colorimetric detection is realized. According to the present invention, the linear amplification mode and the index amplification mode are ingeniously fused, the heterojunction nano-enzyme is used to enhance the signal, and the kit has advantages of high sensitivity (the detection limit can achieve 1.39 fM), strong specificity, simple operation, no complex instrument, visual detection realization and the like, and has wide application prospects in the fields of early cancer screening and immediate cancer diagnosis.