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32 results about "Limiting amplifier" patented technology

Limiting Amplifiers are widely used in instantaneous frequency and phase measurement receivers. The most important performance requirement of a limiting amplifier is to minimize output power variations, and provide a constant output over a wide input dynamic range.

Hundred-time-frequency ultra-wideband frequency conversion circuit, structure and miniaturization design method thereof

The invention provides a hundred-time frequency range ultra-wideband frequency conversion circuit, a hundred-time frequency range ultra-wideband frequency conversion structure and a miniaturization design method of the hundred-time frequency range ultra-wideband frequency conversion circuit. The hundred-time frequency range ultra-wideband frequency conversion circuit comprises an amplitude limiting amplification circuit, the frequency division preselection filtering module is used for carrying out segmented filtering on the ultra wide band radio frequency signal so as to reduce the influence of a harmonic signal and an out-of-band spurious signal on the circuit; the multi-stage frequency mixing module is used for mixing frequency; the local oscillation module is used for driving the multi-stage frequency mixing link to perform frequency conversion; the ultra-wideband frequency conversion circuit realizes ultra-wideband frequency conversion. The invention further designs a frequency conversion structure based on the circuit, the structure adopts a ceramic three-dimensional stacked structure design, grooves are formed in corresponding ceramic tube shells, the corresponding circuits are arranged in the corresponding grooves or formed cavities, and the circuits are isolated through a sealing process; the problem of low integration level of a circuit system in the prior art is solved through the frequency conversion structure.
Owner:GREAT MICROWAVE TECH CO LTD

Wireless optical communication system adopting amplitude limiting amplification method

The invention discloses a wireless optical communication system adopting an amplitude limiting amplification method, which relates to the technical field of wireless optical communication and comprises a transmitting subsystem and a receiving subsystem. The transmitting subsystem is used for generating a serial signal, processing the serial signal, converting the serial signal into an optical signal and transmitting the optical signal; and the receiving subsystem is used for receiving and converting the optical signal into a current signal, converting the current signal into a signal in a voltage form, amplifying the signal, performing waveform shaping and effective bandwidth expansion on the amplified signal through the nonlinear amplitude limiting characteristic of a bandwidth expansion module, and decoding and recovering the signal after bandwidth expansion. According to the invention, the bandwidth of the system is directly expanded by using the nonlinear amplitude limiting characteristic of the amplitude limiting amplifier, so that Gbps-level transmission is realized, and the rate bottleneck of the traditional LED system is overcome. Complex transmitting end equalization is not needed, the design is simplified, the robustness is enhanced, and the stability requirement of a satellite-borne environment high-speed link is met.
Owner:TECH & ENG CENT FOR SPACE UTILIZATION CHINESE ACAD OF SCI

High-power dual-coupling detection amplitude limiting circuit

PendingCN120811307ALimiting amplitude using diodesMicrowaveHemt circuits
The invention relates to a high-power dual-coupling detection amplitude limiting circuit, which belongs to the field of microwave amplitude limiters and comprises a pre-stage amplitude limiting circuit, an auxiliary detection network and a post-stage amplitude limiting circuit which are sequentially connected along a main signal path, and the auxiliary detection network is used for reducing the power input to the post-stage amplitude limiting circuit by coupling input power before the detector tube D1 of the pre-stage amplitude limiting circuit is not fully conducted, and assisting the conduction of the PIN tube in the pre-stage amplitude limiting circuit. According to the high-power dual-coupling detection amplitude limiting circuit, the auxiliary detection network is added on the basis of a traditional semi-active circuit structure, and excessive radio-frequency power leaked into the rear-stage amplitude limiting circuit is coupled out from a main signal path through the auxiliary detection network before a detector tube of the front-stage amplitude limiting circuit is not fully conducted; therefore, the input power of the PIN tube in the post-stage amplitude limiting circuit is reduced, and the PIN tube is not burnt down; and meanwhile, the part of power can be used for assisting the conduction of a PIN tube in preceding stage amplitude limiting.
Owner:XIDIAN UNIV

A transimpedance amplifier integrating automatic reset and fast burst response

The application relates to a trans-impedance amplifier integrated with automatic reset and fast burst response, which comprises a trans-impedance amplifier front-end circuit, a reset signal automatic generation circuit in communication with the trans-impedance amplifier front-end circuit and an adjustable low-pass filter circuit; the adjustable low-pass filter circuit is in communication with an output signal of the trans-impedance amplifier front-end circuit and in communication with reset signals RST and inverse reset signals RSTB generated by the reset signal automatic generation circuit; the adjustable low-pass filter circuit is used for controlling MOS variable resistors and MOS switches arranged in the adjustable low-pass filter circuit according to the reset signals RST and the inverse reset signals RSTB and forming a low-pass filter with adjustable cut-off frequency, and a signal output by the low-pass filter with adjustable cut-off frequency conforms to a mean interval of a voltage signal output by the trans-impedance amplifier front-end circuit. An external RESET signal provided by an MCU is no longer needed to complete fast burst response of chips such as a trans-impedance amplifier, a limiting amplifier and a CDR.
Owner:WUHAN FISILINK MICROELECTRONICS TECH CO LTD

20GHz large dynamic range logarithmic detector

The invention discloses a 20 GHz large dynamic range logarithmic detector, and belongs to the field of broadband detectors. The 20GHz large dynamic range logarithmic detector comprises a limiting amplifier module, a rectifier module and an adder module. Wherein the limiting amplifier module is used for carrying out limiting amplification on an input signal; the rectifier module is used for converting an input signal of the limiting amplifier module into a detection current; and the adder module is used for gathering the detection current of the plurality of rectifier modules to a resistor and converting the detection current into voltage output. According to the invention, the wide-frequency-range input and large-dynamic-range output functions are realized, the wider signal transmission rate can be covered, the larger signal power range can be covered, and the strict requirements of high-integration-level, high-precision, high-sensitivity and large-dynamic-range receivers and other systems on the performance of the detector can be met.
Owner:58TH RES INST OF CETC

Multi-mode optical fiber PON system and multi-mode PON optical module

The invention discloses a multimode optical fiber PON (Passive Optical Network) system and a multimode PON optical module. The multimode optical fiber PON system consists of a multimode OLT (Optical Line Terminal) optical module, a multimode main optical fiber, a multimode optical splitter, a multimode branch optical fiber and a multimode ONU (Optical Network Unit) optical module, according to the multimode OLT optical module and the multimode ONU optical module, a laser, a laser driver, a detector, a transimpedance amplifier, a limiting amplifier and the like are directly mounted on a printed circuit board by adopting a planar optical waveguide assembly and a COB (Chip On Board) mode, so that photoelectric hybrid integrated packaging is realized, and the miniaturization design of the optical module is realized; the planar optical waveguide assembly realizes multiplexing transmission of two wavelength multimode laser beams through a 45-degree reflecting surface and a 45-degree placed multimode light splitting sheet structure; the welding type pin row connector ensures reliable fixation of the optical mode electrical interface, and the clamping jaw structure and the optical fiber contact pin of the multimode optical fiber assembly realize the anti-vibration pluggable optical interface design. The multimode optical fiber PON system provided by the invention meets the requirement of the system for point-to-multipoint optical fiber transmission in a short-distance range with low power consumption, low cost and high reliability.
Owner:HISENSE & JONHON OPTICAL ELECTRICAL TECH CO LTD

Automatic RF output power-limiting amplifier with dynamic feedback

An amplifier includes a gain stage having a gain stage input and a gain stage output and an impedance matching circuit connected to the gain stage output, the impedance matching circuit including an input and an output. The amplifier also includes a coupling circuit connected to the input of the impedance matching circuit and a shorting circuit connected to the output of the impedance matching circuit. The coupling circuit provides a voltage to the shorting circuit that causes the shorting circuit create a short to ground through a reflecting capacitor which causes a reflection to be provided to the output of the impedance matching circuit and that is transmitted to the coupling circuit to increase the voltage provided to the shorting circuit by the coupling circuit.
Owner:RAYTHEON CO

Optical module

In the optical module provided by the invention, a first optical receiving part receives a fourth wavelength optical signal, a fifth wavelength optical signal and a sixth wavelength optical signal reflected by a first reflector, and outputs a first voltage signal, a second voltage signal or a third voltage signal; a golden finger, an MCU, a first limiting amplifier, a second limiting amplifier and a filter circuit are arranged on the circuit board; the input end of the first limiting amplifier and the input end of the second limiting amplifier are connected with a first light receiving part through a filter circuit; the filter circuit transmits a second voltage signal to the first limiting amplifier, so that the first limiting amplifier processes the second voltage signal and transmits the second voltage signal to the golden finger; and the MCU is in control connection with the second limiting amplifier, so that the second limiting amplifier processes the first voltage signal or the third voltage signal through the control signal and then transmits the first voltage signal or the third voltage signal to the golden finger through the corresponding output end.
Owner:HISENSE BROADBAND MULTIMEDIA TECH

A training control method and optical module

ActiveCN117200886BOptical ModuleMonoboard
The training control method and optical module provided in this application include: querying whether the training status control command flag is a first preset command value; if it is the first preset command value, then causing the laser driver to transmit a second electrical signal sent by the host computer to a limiting amplifier, so that the limiting amplifier transmits the electrical signal back to the host computer via a gold finger, wherein the host computer is the host computer to which the optical module is connected. When the training status control command flag in the optical module is the first preset command value, the training control method and optical module provided in this application control the optical module to enter training mode, causing the laser driver to transmit an electrical signal to a limiting amplifier, and then transmitting the electrical signal back to the host computer via a gold finger. This effectively reduces jitter accumulation during electro-optical conversion and transmission, and assists in accurately assessing the degradation of electrical signals from each port on the system board to the MAC chip.
Owner:HISENSE BROADBAND MULTIMEDIA TECH

Fast common mode recovery circuit and method for burst mode limiting amplifier

The application provides a low-cost design scheme suitable for common-mode recovery of burst-mode limiting amplifier. The method of variable time constant can shorten the common-mode recovery time to 14 ns, meeting the requirements of passive optical network. The design is simple and feasible, which not only retains the advantages of simple design of alternating current coupling of front and rear stages, but also avoids the long common-mode recovery time caused by alternating current coupling in the burst-mode limiting amplifier, which is difficult to meet the index requirements of the loop working speed better than 25.6 ns in the burst-mode limiting amplifier.
Owner:NANTONG UNIV

Broadband logarithmic detector

The invention relates to a broadband logarithmic detector. The amplitude limiting amplifier comprises an amplitude limiting amplifier link used for carrying out amplitude limiting amplification on a signal to be detected, amplitude limiting amplification gains comprise a first amplitude limiting amplification gain or a second amplitude limiting amplification gain, and the numerical value of the first amplitude limiting amplification gain is larger than that of the second amplitude limiting amplification gain, when the amplitude limiting amplification gain of the amplitude limiting amplifier link is the first amplitude limiting amplification gain, the amplitude limiting amplifiers of the first stage are connected, and each amplitude limiting amplifier provides a single-stage first amplification gain; when the amplitude-limiting amplification gain of the amplitude-limiting amplifier link is a second amplitude-limiting amplification gain, accessing a second-stage amplitude-limiting amplifier, and providing a single-stage second amplification gain by each amplitude-limiting amplifier; the first stage number is smaller than the second stage number, and the single-stage first amplification gain is larger than the single-stage second amplification gain. According to the method, translation of the RSSI output characteristic curve of the logarithmic detector can be effectively stabilized, and the output characteristic and the process robustness of the logarithmic detector are improved.
Owner:无锡芯亿集成电路有限公司

Dual-polarized radio frequency transceiver system and package structure

This application discloses a dual-polarization radio frequency transceiver system and its package structure, including: a power amplifier chip, a limiting amplifier chip, a circulator, a switching chip, a first microstrip filter stub, and a second microstrip filter stub. In the transmit state, the circulator is used to unidirectionally transmit the radio frequency signal input to the power amplifier chip to the switching chip. The switching chip can switch the transmission path of the radio frequency signal so that the radio frequency signal is processed by the first microstrip filter stub or the second microstrip filter stub before being output. In the receive state, the circulator is used to unidirectionally transmit the radio frequency signal input to the first microstrip filter stub or the second microstrip filter stub after passing through the switching chip to the limiting amplifier chip before being output. This invention realizes the switching between horizontal and vertical polarization channels through the switching chip, and improves the second harmonic suppression ratio by utilizing the first and second microstrip filter stubs. The system is integrated into a miniaturized package structure and has good heat dissipation.
Owner:BEIJING INST OF RADIO MEASUREMENT

Optical module

The optical module provided by the utility model comprises a circuit board which is provided with a limiting amplifier and a reset signal generation circuit; the light receiving component comprises a photoelectric detector and a trans-impedance amplifier, the photoelectric detector is used for receiving burst light receiving signals, the input end of the trans-impedance amplifier is electrically connected with the photoelectric detector, and the output end of the trans-impedance amplifier is electrically connected with the limiting amplifier; the reset signal generation circuit comprises: a time delay sub-circuit, the input end of which is used for inputting a detection signal and performing time delay processing on the detection signal; the exclusive-OR gate comprises a first input end and a second input end; the first input end is used for inputting a detection signal, and the second input end is connected with the output end of the delay sub-circuit; the output end of the exclusive-OR gate is connected with the reset input end of the transimpedance amplifier, and the exclusive-OR gate outputs a first reset signal based on a detection signal and a delayed detection signal, so that the transimpedance amplifier is reset based on the first reset signal. And rapid resetting of the transimpedance amplifier is facilitated.
Owner:HISENSE BROADBAND MULTIMEDIA TECH

Bluetooth microphone improvement circuit and Bluetooth microphone

The utility model belongs to the technical field of microphones, and particularly relates to a Bluetooth microphone improvement circuit and a Bluetooth microphone, the Bluetooth microphone improvement circuit comprises a Bluetooth audio processing chip and an amplitude limiting circuit, the Bluetooth audio processing chip is connected with the amplitude limiting circuit, the amplitude limiting circuit is also connected with an electret MIC, and the Bluetooth audio processing chip is also connected with a Bluetooth antenna. By adding the amplitude limiting circuit, the signal amplitude of the Bluetooth audio processing chip is limited, signal overload is avoided, and tone quality distortion and noise are prevented.
Owner:SHENZHEN BOECA PHOTOELECTRICITY TECH CO LTD

Improved error correction for high-speed optical networks

Systems and techniques for improved error correction for high-speed optical networks are described herein. An optical signal is received and the optical signal is converted into an electrical signal. The electrical signal is amplified through a trans-impedance amplifier to produce an amplified signal. The amplified signal is normalized using a limit amplifier to generate a normalized signal. Bit values are determined from the normalized signal and a corresponding probability bit is generated for each bit value using a threshold detector. The bit values and the corresponding probability bit are encoded into a four-level pulse-amplitude modulation (PAM-4) signal. The PAM-4 signal is transmitted to an application-specific integrated circuit (ASIC) for data recovery and error correction processing.
Owner:BERNARD CHRISTOPHER THOMAS +2

10-gigabit optical receiving circuit

The utility model provides a 10-gigabit optical receiving circuit, which comprises a photodiode, a trans-impedance amplifier, a differential amplifier and a limiting amplifier, the photodiode is connected in series between the two input ends of the transimpedance amplifier; the resistor R1 is connected in series between the first input end of the differential amplifier and the first output end of the trans-impedance amplifier, and the capacitor C3 is connected in parallel with the resistor R1; the resistor R2 is connected in series between the second input end of the differential amplifier and the second output end of the trans-impedance amplifier, and the capacitor C4 is connected in parallel with the resistor R2; the resistor R3 is connected in series between the first input end of the differential amplifier and the first output end of the differential amplifier, and the resistor R4 is connected in series between the second input end of the differential amplifier and the second output end of the differential amplifier; the output end of the differential amplifier is sequentially connected with the limiting amplifier and the input end of the signal processing module. Therefore, according to the utility model, the high-frequency response is enhanced, and the influence of noise is reduced.
Owner:ZHENGZHOU XINDA ADVANCED TECH RES INST

Wideband log detector

The present application relates to a kind of wideband log detector.It includes the limiting amplifier link for the limiting amplification of signal to be detected, the limiting amplification gain includes first limiting amplification gain or second limiting amplification gain, the value of first limiting amplification gain is greater than the value of second limiting amplification gain, wherein, when the limiting amplification gain of limiting amplifier link is first limiting amplification gain, access the limiting amplifier of first stage number, and each limiting amplifier provides single-stage first amplification gain;When the limiting amplification gain of limiting amplifier link is second limiting amplification gain, access the limiting amplifier of second stage number, and each limiting amplifier provides single-stage second amplification gain;First stage number is less than second stage number, and single-stage first amplification gain is greater than single-stage second amplification gain.The present application can effectively stabilize the translation of the RSSI output characteristic curve of log detector, improve the output characteristic and process robustness of log detector.
Owner:无锡芯亿集成电路有限公司

An OLT device based on optical module standard package

The utility model discloses an OLT equipment based on optical module standard package adopts standard SFP+ / XFP package shell, contain: SC / LC optical interface connection TO package's 1577nm electric absorption modulation laser, 1490nm distributed feedback laser and integrated TIA's 10G / 1.25G APD detector, laser drive unit contains input buffer and pre -drive circuit, burst receiving unit contains burst across resistance amplifier and limiting amplifier circuit, contain the XGSPON / XGPON / GPON MAC processing and management chip of meeting ITU-T G.9807.1, ITU-T G.987.1 and ITU-T G.984.x protocol specification through high -speed SerDes link connection support XGMII / HSGMII / SGMII interface's ethernet switch chip, and the equipment control unit integrates SFP+ / XFP management interface, and the golden finger interface circuit is directly connected switch chip through circuit board transmission line, and each unit is connected through optical fiber channel, circuit wiring and control bus, realizes OLT function modularization integration, reduces the deployment cost and power consumption.
Owner:SICHUAN AOTENG OPTOELECTRONICS TECHNOLOGY CO LTD

Error Correction for High-Speed Optical Networks

Systems and techniques for are described herein. An optical signal is received and the optical signal is converted into an electrical signal. The electrical signal is amplified through a trans-impedance amplifier to produce an amplified signal. The amplified signal is normalized using a limit amplifier to generate a normalized signal. Bit values are determined from the normalized signal and a corresponding probability bit is generated for each bit value using a threshold detector. The bit values and the corresponding probability bit are encoded into a four-level pulse-amplitude modulation (PAM-4) signal. The PAM-4 signal is transmitted to an application-specific integrated circuit (ASIC) for data recovery and error correction processing.
Owner:CALIX INC

Nondegenerate through quantum-limited amplifier

A device comprises a nondegenerate through quantum-limited amplifier comprising a first port, a second port, and a third port. The first port is configured to receive first quantum signals which comprise frequencies within a first frequency band. The second port is configured to receive second quantum signals which comprise frequencies within a second frequency band, which is non-overlapping with the first frequency band. The nondegenerate through quantum-limited amplifier is configured to amplify the first quantum signals, amplify and convert the frequencies of the second quantum signals to frequencies within the first frequency band, and output the amplified first quantum signals and the amplified frequency-converted second quantum signals from the third port.
Owner:INTERNATIONAL BUSINESS MACHINE CORPORATION

Broadband gain-controllable limiting amplifier circuit and optical module

The embodiment of the utility model provides a broadband gain-controllable limiting amplifier circuit and an optical module. The broadband gain-controllable limiting amplifier circuit comprises a plurality of differential amplification modules which are connected in series and used for amplifying input signals step by step; the differential amplification module comprises a differential amplification circuit, a proportional current source and a current adjusting circuit, and the proportional current source is used for outputting a second current at an output end of the proportional current source according to a preset proportion and a first current input at an input end of the proportional current source to serve as a tail current of the differential amplification circuit; the current adjusting circuit comprises a plurality of parallel current sources for inputting current to the input end of the proportional current source, at least one of the parallel current sources is provided with a corresponding switch component, and the switch component is used for switching on or switching off the current input to the input end of the proportional current source by the corresponding current source so as to adjust the first current.
Owner:GUSU LAB OF MATERIALS +1

Receiving circuit of fourth-order pulse amplitude modulation signal and high-speed communication chip

ActiveCN121567512ALine balance variation compensationLine-faulsts/interference reductionCircuit complexitySoftware engineering
The invention discloses a fourth-order pulse amplitude modulation signal receiving circuit and a high-speed communication chip. The receiving circuit of the fourth-order pulse amplitude modulation signal comprises an equalization module, a level shifting and amplitude limiting amplification module, a clock data recovery module, a sampling module and a decoding module, the clock data recovery module is connected with the level shift and amplitude limiting amplification module, and the clock data recovery module is used for recovering a sampling clock according to the input second output signal and sending the sampling clock to the sampling module; the sampling module is connected with the clock data recovery module and is used for synchronously sampling the first output signal, the second output signal and the third output signal by using a sampling clock and outputting a thermometer code; and the decoding module is connected with the sampling module and is used for decoding the thermometer code, converting the thermometer code into two paths of non-return-to-zero code signals and outputting the two paths of non-return-to-zero code signals. According to the invention, the circuit complexity can be reduced, the circuit has the advantage of simple structure, and excellent performance can be realized.
Owner:CIX TECH (SUZHOU) CO LTD

A dual-channel and miniaturized optical module driving circuit and dual-channel optical module

The application discloses a kind of double-channel and miniaturized optical module drive circuit and double-channel optical module, it is related to optical module technical field, double-channel optical module includes first channel and second channel, the first channel and the second channel all include laser diode, limiting amplifier, electroabsorption modulated laser and avalanche photodiode;Optical module drive circuit includes interface unit, control unit and drive unit;Interface unit is connected with the control unit, the control unit is connected with the drive unit;The drive unit is connected with the laser diode, limiting amplifier, electroabsorption modulated laser and avalanche photodiode of the first channel and the second channel respectively.The double-channel parallel processing mechanism of the application is realized by independent signal path The synchronous reception and transmission of two-way data, break through the bandwidth limit of traditional single-channel architecture.At the same time, the centralized control of double-channel, significantly improve the integration, reduce the volume of equipment as a whole.
Owner:POTRON TECH CO LTD

A receiving circuit of a four-order pulse amplitude modulation signal and a high-speed communication chip

ActiveCN121567512BSuppress correlation jittersuppress jitterLine balance variation compensationLine-faulsts/interference reductionCircuit complexitySoftware engineering
The application discloses a kind of fourth-order pulse amplitude modulation signal receiving circuit and high-speed communication chip.Fourth-order pulse amplitude modulation signal receiving circuit includes: equalization module, level shift and limiting amplifier module, clock data recovery module, sampling module and decoding module;Clock data recovery module is connected with level shift and limiting amplifier module, clock data recovery module is used to recover sampling clock according to the second output signal input and send to sampling module;Sampling module is connected with clock data recovery module, and sampling module is used to use sampling clock respectively to first output signal, second output signal and third output signal are synchronously sampled, and output thermometer code;Decoding module is connected with sampling module, and decoding module is used to decode processing to thermometer code, and is converted into two-way non-return-to-zero code signal after output.This application can reduce circuit complexity, with the advantage of simple structure, can realize excellent performance.
Owner:CIX TECH (SUZHOU) CO LTD

12-path photoelectric and electro-optical conversion integrated optical module

The 12-path photoelectric and electro-optical conversion integrated optical module comprises a conversion control part which comprises a controller, a 1 * 12-path VCSEL driver and a 1 * 12-path limiting amplifier, and the 1 * 12-path VCSEL driver and the 1 * 12-path limiting amplifier are used in cooperation with the controller. One end of the 1 * 12-path VCSEL driver is connected with the differential signal access end to access 12 paths of differential signals, and the other end of the 1 * 12-path VCSEL driver is connected with the 12-path optical signal output end to form a 12-path electro-optical conversion structure; one end of the 1 * 12-path limiting amplifier is connected with the 12-path optical signal input end, 12-path optical signals are accessed, the other end of the 1 * 12-path limiting amplifier is connected with the differential signal output end, and a 12-path photoelectric conversion structure is formed; the 12-path electro-optical conversion structure is combined with the 12-path photoelectric conversion structure to form a 12-path photoelectric and electro-optical conversion integrated structure; the 12-path electro-optical conversion structure is used as a transmitting end and converts an input electric signal into an optical signal to be output; the 12-path photoelectric conversion structure is used as a receiving end and converts an input optical signal into a differential signal to be output; and a 12-path transmit-receive integrated optical module structure is formed through combination.
Owner:JIANGSU ALLRAY

Burst-mode optical receiver circuit with built-in reset signal to reduce settling time

This invention discloses a burst-mode optical receiver circuit with a built-in reset signal to reduce settling time. Belonging to the field of analog integrated circuits, it amplifies the current signal generated by a photodiode through a pre-amplifier of a transimpedance amplifier. A variable gain amplifier then provides variable amplification within a certain dynamic range. The variable gain amplifier employs source degradation resistors and capacitors to improve linearity. The output signal of the variable gain amplifier is further amplified to a limited state by a limiting amplifier in the feedback loop and sent to an envelope detector to detect the envelope information of the data stream. This envelope information is compared with the DC voltage at the detection point of the transimpedance amplifier by a comparator. The output signal undergoes pulse width broadening to generate a pulse reset signal, which in turn adjusts the loop parameters of the transimpedance amplifier, achieving rapid circuit stabilization. This invention has a simple structure and can significantly reduce settling time by adjusting the slew rate of the comparator and the pulse width of the pulse width broadening circuit, while also providing stronger anti-interference capabilities.
Owner:SOUTHEAST UNIV

Optical module

In the optical module provided by the invention, a first optical receiving part receives a fourth wavelength optical signal, a fifth wavelength optical signal and a sixth wavelength optical signal reflected by a first reflector, and outputs a first voltage signal, a second voltage signal or a third voltage signal; a golden finger, an MCU, a first limiting amplifier, a second limiting amplifier and a filter circuit are arranged on the circuit board; the input end of the first limiting amplifier and the input end of the second limiting amplifier are connected with a first light receiving part through a filter circuit; the filter circuit transmits a second voltage signal to the first limiting amplifier, so that the first limiting amplifier processes the second voltage signal and transmits the second voltage signal to the golden finger; and the MCU is in control connection with the second limiting amplifier, so that the second limiting amplifier processes the first voltage signal or the third voltage signal through the control signal and then transmits the first voltage signal or the third voltage signal to the golden finger through the corresponding output end. According to the optical module provided by the embodiment of the invention, the size of the optical module is convenient to control.
Owner:HISENSE BROADBAND MULTIMEDIA TECH

Full-localization multichannel T / R assembly

The invention relates to a full-localization multichannel T / R assembly, and belongs to the technical field of phased array radars. The number of the receiving and transmitting modules is six, each receiving and transmitting module is provided with four receiving and transmitting channels, each receiving and transmitting channel is composed of a ring isolation unit, a coupling detection unit, a power amplifier, a switch amplitude limiting amplification unit, a filter, a multifunctional unit and a power division network unit, and the six receiving and transmitting modules output 24 paths of signals in total; the controller takes a double-sided printed board as a carrier, connectors are arranged on both sides of the controller, the controller is vertically interconnected with the upper layer transceiver module and the lower layer transceiver module, the excitation power division / echo synthesis unit, the test power division / coupling unit and the transceiver modules are mutually vertical interconnection structures, and the transceiver modules, the band-pass filter and the power supply module are mutually horizontal interconnection structures. Intercommunication and interconnection of electric signals and radio frequency signals are completed to form a whole, and the channel density is increased; and in combination with the transmit-receive sharing type transmit-receive module, the internal integration level of the T / R assembly is improved, the use amount of the common power supply module and the controller is reduced, and the manufacturing cost is effectively reduced.
Owner:JINGZHOU NANHU MACHINERY CO LTD

Amplitude limiting circuit and earphone

The utility model discloses an amplitude limiting circuit and an earphone. The amplitude limiting circuit comprises a first signal branch and a second signal branch. The power input end is connected with the first signal branch, and the grounding end is connected with the second signal branch; the first amplitude limiting module comprises a first resistor and a first diode module, the first end of the first diode module is connected with the first signal branch, the second end of the first diode module is connected with the second signal branch, and the first resistor is connected between the power input end and the first diode module; the second amplitude limiting module comprises a second resistor and a second diode module, the first end of the second diode module is connected with the second signal branch, the second end of the second diode module is connected with the first signal branch, and the second resistor is connected between the grounding end and the second diode module. According to the utility model, the self-excitation noise can be effectively suppressed, and the user experience is improved.
Owner:SHENZHEN GRANDSUN ELECTRONICS CO LTD

Surface acoustic wave filtering amplitude limiter

The invention belongs to the technical field of electromagnetic protection, and relates to a surface acoustic wave filtering amplitude limiting device, which comprises a piezoelectric crystal and more than one group of filtering amplitude limiting units, the filtering amplitude limiting unit comprises an interdigital transducer, an energy self-adaptive conversion region and an energy absorption region; the interdigital transducer is arranged at the middle position of the filtering amplitude limiting unit so as to convert the electromagnetic wave signal into a surface acoustic wave and transmit the surface acoustic wave into the energy self-adaptive conversion area; the energy adaptive transformation regions are arranged on two sides of the interdigital transducer, comprise columnar chambers distributed in an array and non-Newtonian fluids arranged in the columnar chambers, and are used for performing nonlinear response on the amplitude of the surface acoustic wave, so that frequency selective filtering is realized in a low-power signal input state, and surface acoustic wave transmission is realized in a high-power signal input state; and the energy absorption regions are arranged on the two sides of the energy self-adaptive transformation region to absorb the transmitted surface acoustic waves so as to realize amplitude limiting protection. According to the invention, filtering and amplitude limiting can be realized simultaneously.
Owner:河北水利电力学院