396 results about "Frequency mixer" patented technology

The invention discloses a beat frequency comparison device mediated by an optical frequency comb. The beat frequency comparison device comprises the optical frequency comb, a first frequency stabilized laser, a first beat frequency device, a first frequency mixer, a first high-pass filter, a second frequency stabilized laser, a second beat frequency device, a second frequency mixer, a second high-pass filter, a DDS signal generator, a third frequency mixer and a low-pass filter. Frequency-stabilized lasers output by the first frequency-stabilized laser and the second frequency-stabilized laser and an optical frequency comb output by the optical frequency comb are subjected to beat frequency in the first beat frequency device and the second beat frequency device respectively, and first beat frequency and second beat frequency are obtained; the first beat frequency and the second beat frequency are mixed with the carrier envelope offset frequency of the optical frequency comb, and a first sum frequency and a second sum frequency are filtered out; the first sum frequency obtains a synthetic frequency through direct digital frequency synthesis; the second sum frequency and the synthetic frequency are mixed in the third mixer, and then the difference frequency is filtered out through the low-pass filter. According to the invention, beat frequency comparison of frequency-stabilized lasers with different wavelengths can be realized, and the influence of the stability of the optical frequency comb is avoided.

Circuitry is provided that includes a matching circuit, a first mixer coupled to the matching circuit and configured to receive a signal with an oscillation frequency, a second mixer coupled to the matching circuit, a first transmission line path coupled between the matching circuit and an input of the first mixer, and one or more capacitors coupled to the input of the first mixer and configured to reject signals at a harmonic frequency of the oscillation frequency. The wireless circuitry can further include a second transmission line path coupled between the matching circuit and an input of the second mixer. The transmission line path can include a first transmission line for conveying signals between the matching circuit and the first mixer, a second transmission line for conveying signals between the matching circuit and the first mixer, and a floating transmission line interposed between the first and second transmission lines.

In one embodiment, an apparatus includes a baseband processor to generate a baseband signal and a digital pre-distortion (DPD) circuit to pre-distort the baseband signal with compensation information obtained from a lookup table. The lookup table may have a plurality of entries each to store a pre-distortion value, the lookup table to be addressed based on a target output power level of the baseband signal. The apparatus also may include a converter to convert the pre-distorted baseband signal to an analog signal and radio frequency (RF) circuitry comprising: a mixer to upconvert the analog signal to a pre-distorted RF signal, and a power amplifier to amplify the pre-distorted RF signal.

The invention relates to a multichannel down-conversion chip, a multichannel down-conversion circuit and a receiver, and the chip comprises a local oscillator signal processing module which accesses a local oscillator signal, carries out the amplification and power division of the local oscillator signal, and obtains a plurality of local oscillator power division signals; based on the local oscillator power division signal, phase shifting is carried out to obtain a phase-shifted local oscillator signal, and the phase-shifted local oscillator signal is input of a frequency mixer in a corresponding channel; each channel of the multi-channel module is provided with a radio frequency amplifier, a frequency mixer and an intermediate frequency amplifier which are connected in sequence, the input end of each radio frequency amplifier is used for accessing a received radio frequency signal, and the output end of each intermediate frequency amplifier is the output end of the corresponding channel; by adopting the chip, the number of components required in the down-conversion circuit can be effectively reduced, the manufacturing cost of the down-conversion circuit is reduced, and the plurality of components such as the radio frequency amplifier, the frequency mixer and the intermediate frequency amplifier are integrated in the same chip, so that the size of the down-conversion circuit can be reduced, and the miniaturization requirement can be met.

The invention discloses a frequency mixer test method, and relates to the technical field of microwave radio frequency test, and the method comprises the following steps: S1, building a test platform; s2, calibrating the test platform; s3, testing indexes; and according to the received reflection signal and standing wave signal, port isolation test, frequency conversion loss test, port standing wave test and output 1dB compression point test are carried out on the mixer to be tested, and a test curve of each index is drawn after the test is completed. According to the method, all key indexes of the mixer can be tested at different power frequency points through one-time calibration, meanwhile, standing wave testing of the LO port under high power can be achieved, the testing efficiency and accuracy are greatly improved, and the technical problems that in the prior art, multiple times of calibration are needed in the testing process, and the testing efficiency is low are solved.

Architectures are presented for transmitters and receivers that use a harmonic rejection mixer that uses a 6-phase clock signal, while also using a differential in-phase / quadrature input signal (for the transmitter) or output signal (for the receiver). This results in crosstalk between the in-phase and quadrature components, where a digital correction circuit forms a linear combination of the baseband I / Q signals to generate the I / Q for the mixer in order to obtain the desired baseband signal. By using a differential I / Q signal, only two DACs / ADCs are needed, saving circuitry area and power consumption, while providing strong 2nd, 3rd, and 4th clock harmonic rejection. The clock signal can be composed of two sets of 3-phase signals, each signal having a 33% duty cycle.

A method and system for testing the conversion losses of terahertz mixers capable of eliminating the influence of radio frequency sources includes grouping a mixer to be tested and at least two reference mixers in pairs; in each group, inputting a signal of a preset frequency and a preset power at an intermediate frequency port of a first mixer, and after up-conversion, outputting same to a second mixer to be down-converted, so as to obtain an output power with the frequency same as the preset frequency, and obtain the relationship between a first output power and a first preset power and the losses of two mixers; according to the relationship between the loss of the mixer in each group and the power, obtaining the loss of the mixer to be tested.

This invention discloses a pilot-type carrier phase recovery circuit and a reverse antenna array system, belonging to the field of 5G millimeter-wave communication. The pilot-type carrier phase recovery circuit includes a digital phase detector, a quadrature mixer, a quadrature voltage-controlled oscillator, a low-pass filter, a high-pass filter, a polyphase filter, a loop filter, a first intermediate frequency amplifier, a second intermediate frequency amplifier, a first shaping circuit, and a second shaping circuit. Applied to a reverse antenna array system, this invention performs carrier phase recovery on the data signal and pilot signal output from the receiver, separating the data signal without spatial phase information and the spatial phase information used for reverse transmission. This invention enables high-order modulation full-duplex communication and real-time tracking of moving targets, featuring high integration, small area, high communication speed, and strong anti-interference capability.

A transceiver and an electronic device including the same are provided. The transceiver includes a first mixer, a noise reduction circuit, a first amplifier, a second amplifier, and an input / output (I / O) port. The first mixer receives first data and a first clock signal, and generates a first signal to be transmitted to an external device based on the first data and the first clock signal. The noise reduction circuit provides a first clock signal to the first mixer. The first amplifier amplifies the first signal received from the first mixer. The second amplifier amplifies a second signal received from an external device. The I / O port is shared by the first amplifier and the second amplifier and is configured to output the amplified first signal and receive the second signal. The noise reduction circuit activates the first clock signal during an activation time interval of the first data and deactivates the first clock signal during a deactivation time interval of the first data.

An antenna and receiver design is described herein that allows a spacecraft to safely and accurately perform an autonomous flight safety system, an ascent, an entry, a re-entry, a landing, and / or an orbit determination. For example, a spacecraft can be equipped with 180-degree dual-opposed antennas and two receivers. A signal captured by a first antenna can be routed to a secondary radio frequency (RF) of the first receiver and to a combiner. A signal captured by a second antenna can be routed to a secondary RF of the second receiver and to the combiner. The mixer can perform the phase combination operation on the signals captured by the first receiver and the second receiver to produce a phase combined signal, and can route the phase combined signal to the primary RF of the first receiver and to the primary RF of the second receiver.

Certain aspects provide a circuit for frequency translation. The circuit includes first mixer circuitry coupled to a load circuit and having a first mixer configured to generate, based on a first differential input signal and a second differential input signal, a first portion of a frequency translated differential signal to be provided to the load circuit, and a second mixer configured to generate, based on a third differential input signal and a fourth differential input signal, a second portion of the frequency translated differential signal. The circuit also includes second mixer circuitry coupled to another load circuit and having a third mixer configured to generate, based on the first differential input signal and the fourth differential input signal, a first portion of another frequency translated differential signal, and a fourth mixer configured to generate, based on the third differential input signal and the second differential input signal, a second portion of the another frequency translated differential signal.

A signal processing apparatus, a detection apparatus and a terminal device, which relate to the technical field of detection, and are used for reducing the costs and occupied spaces of optical delay lines. The signal processing apparatus comprises a first frequency modulation group (11), a second frequency modulation group (21) and an optical delay line (400); the first frequency modulation group (11) comprises a first frequency modulation photoelectric loop (110), a second frequency modulation photoelectric loop (210) and a polarization control element (300); the second frequency modulation group (21) comprises a third frequency modulation photoelectric loop (310); the polarization control element (300) is connected among the optical delay line (400), a first beam splitting element (112, 212, 312) in each frequency modulation photoelectric loop (110, 210, 310) and a frequency mixer (114, 214, 314) in each frequency modulation photoelectric loop (110, 210, 310), and is used for outputting optical signals (S11, S21, S31) in the three frequency modulation photoelectric loops (110, 210, 310) to the optical delay line (400) in orthogonal polarization directions, and outputting the delayed optical signals (S11 ', S21 ', S31 ') to the mixer (114, 214, 314) in each frequency modulation optoelectronic circuit (110, 210, 310). The signal processing apparatus can achieve the effect that the three frequency modulation photoelectric loops (110, 210, 310) share the same optical delay line (400), and reduce the number of optical delay lines (400) required to be provided in the signal processing apparatus, and the costs and occupied spaces of the optical delay lines (400).

The invention discloses a full-duplex inter-satellite communication system and method suitable for annular networking, two inter-satellite communication links of a networking satellite have the same transmitting and receiving frequency points and can be interchanged in orbit, the layout problem caused by the isolation design between the two communication links is solved, and the full-duplex inter-satellite communication system and method can work in a frequency division continuous wave communication or frequency division burst communication mode. According to the number of satellites, inter-satellite communication link transmit-receive frequency and working modes are set to ensure link establishment communication of the ring network, multiplexing is performed on the frequency synthesizer module, the intermediate frequency processing module and a radio frequency filter, an intermediate frequency filter and a mixer in the transmit-receive module, product integration is facilitated, and the problems of large product size, heavy weight and high cost are solved.

The application discloses a single-end distributed optical fiber vibration sensor system and a signal processing method, and relates to the technical field of optical fiber vibration sensors. The system comprises a laser source, an electro-optical modulator, a to-be-measured optical fiber, a piezoelectric ceramic, a 1*2 coupler, a frequency mixer, an oscilloscope and a PC end. The laser source transmits laser to the to-be-measured optical fiber after the laser is loaded with a carrier frequency by the electro-optical modulator. The to-be-measured optical fiber changes the phase of the light conducted in the optical fiber after being affected by external environmental vibration. The piezoelectric ceramic generates a vibration signal to modulate the phase information of the to-be-measured optical fiber, and then transmits the vibration signal to the 1*2 coupler. The 1*2 coupler divides the vibration signal into signal light and local oscillator light, and then transmits the signal light and the local oscillator light to the frequency mixer for coherent mixing. The frequency mixer demodulates the phase change. The PC end demodulates and processes the phase change collected by the oscilloscope to obtain vibration information of the external environment. The single-end distributed optical fiber vibration sensor system has a large dynamic range, a long measurement distance, low cost and measurement stability.

The application discloses a terahertz mixer, comprising: a radio frequency input waveguide, a local oscillator input waveguide, a local oscillator filter and an intermediate frequency output waveguide, wherein the intermediate frequency output waveguide comprises a built-in fin line transition structure and a Schottky diode pair; one end of the fin line transition structure is connected with the radio frequency input waveguide, the other end of the fin line transition structure is connected with the local oscillator filter, the Schottky diode pair is connected with one side of the fin line transition structure and connected with an intermediate frequency output port of the intermediate frequency output waveguide; after the local oscillator signal is filtered by the local oscillator filter, the local oscillator signal is transmitted to the fin line transition structure, the radio frequency signal and the local oscillator signal are loaded into the Schottky diode pair through the fin line transition structure for frequency mixing, and the intermediate frequency signal is output through the intermediate frequency output port. In this case, the fin line transition structure simultaneously carries the radio frequency signal and the local oscillator signal, which can realize spatial superposition and power efficient injection of the signals, and has good impedance matching characteristics.

This disclosure provides a digital transmitter, relating to the field of transmitter technology. It includes: a baseband data generation unit for multi-phase output of baseband data; and a basic unit including an I-channel mixer and a Q-channel mixer. The I-channel mixer performs mixing processing on the multi-phase outputs of the positive-phase I-channel baseband data and the negative-phase I-channel baseband data, while the Q-channel mixer performs mixing processing on the multi-phase outputs of the positive-phase Q-channel baseband data and the negative-phase Q-channel baseband data. The positive-phase outputs of the I-channel and Q-channel mixers are respectively connected to the positive-phase RF input of the digital transmitter, and the negative-phase outputs of the I-channel and Q-channel mixers are respectively connected to the negative-phase RF input of the digital transmitter. This disclosure simplifies the circuit structure of traditional digital transmitters and enables effective bandwidth expansion. Furthermore, by introducing multi-tap filtering for the baseband data, better spectrum shaping can be achieved.

The application discloses a kind of very small step local oscillator devices, comprising: reference signal source;DDS synthesizer is used to receive the output signal of reference signal source, and output the first output signal of lower frequency;First filter is used to filter the first output signal, and obtain the first to-be-mixed signal;Frequency multiplier is used to receive the output signal of reference signal source, and output the second output signal of higher frequency;Second filter is used to filter the second output signal, and obtain the second to-be-mixed signal;Mixing frequency ware is used to mix the first to-be-mixed signal and the second to-be-mixed signal, and obtain mixed signal;Third filter is used to filter mixed signal, and obtain phase-locked loop reference signal;Phase-locked loop module is used to receive phase-locked loop reference signal, and output local oscillator signal.It also discloses a kind of very small step local oscillator method.The application is while realizing very small step local oscillator scheme, also has very low decimal step spur.

A circuit includes a mixer having a first input, a second input, and an output. A clock generator has an output coupled to the second input of the mixer. An analog-to-digital converter (ADC) has an input coupled to the output of the mixer and has an output. A spur estimator has a first input, a second input, and an output. The first input of the spur estimator is coupled to the output of the ADC. A spur modification circuit has a first input, a control input and an output. The first input of the spur modification circuit is coupled to the second input of the spur estimator, and the control input is coupled to the output of the spur estimator. A transmitter has an input coupled to the output of the spur modification circuit and has an output coupled to the first input of the mixer.

The utility model relates to a broadband anti-burning anti-crosstalk annular low noise amplifier assembly, which comprises an input end, a low noise amplifier assembly and an output end, the input end is connected with a band-pass filter, and the output end is connected with a low-pass filter; the band-pass filter is connected with the low-noise amplifier assembly, and the low-pass filter is connected with the low-noise amplifier assembly through the down-conversion mixer; the low-noise amplifier assembly is of a multi-stage cascade system structure and comprises a front-stage broadband low-noise amplifier, a rear-stage SPDT radio frequency switch, a biasing circuit with temperature and voltage compensation effects and an ESD protection circuit. The front-stage broadband low-noise amplifier is cascaded with the rear-stage SPDT radio frequency switch; the front-stage broadband low-noise amplifier and the rear-stage SPDT radio frequency switch are respectively cascaded with a biasing circuit with temperature and voltage compensation effects; the utility model has the advantages of reasonable structure, strong anti-interference performance, safety and reliability, and can avoid burnout.

The present application belongs to the technical field of radio frequency microwave integrated circuit design, and specifically relates to a wideband full duplex receiver sharing an interference cancellation circuit. The full duplex receiver of the present application is composed of a receiver module and an interference cancellation circuit. The receiver comprises a transconductance, a mixer, a transimpedance amplifier and a frequency conversion loop. The interference cancellation circuit comprises an input matching network, an input down-mixer, a quadrature selection phase shifter and a baseband variable gain low-pass filter. The interference cancellation circuit transfers the adjustment of the delay and gain in the radio frequency domain to the baseband, so that the overall area and power consumption are small, and the delay amount of 3.86-8.33 ns can be realized in a wide radio frequency band of 0.5-3.5 GHz. Meanwhile, the interference cancellation circuit is synthesized by the mixer in the frequency conversion loop of the receiver to form a double-path cancellation mode, which avoids the interference cancellation circuit being directly connected to the front end of the receiver module, and the noise figure deterioration of the receiver module is very small, only 0.9-1.2 dB.

The invention relates to the field of integrated circuits, and discloses a low-phase noise signal source circuit and radar equipment, and the low-phase noise signal source circuit comprises a four-core F23 type voltage-controlled oscillator which is used for generating a fundamental frequency, a second harmonic and a third harmonic; the harmonic self-mixer is connected with the quad-core F23 type voltage-controlled oscillator, and is used for mixing the fundamental frequency and the third harmonic into a quadruplicated frequency signal and outputting the quadruplicated frequency signal, and mixing the fundamental frequency and the fundamental frequency into a secondary frequency multiplication signal and outputting the secondary frequency multiplication signal; and the amplifier is connected with the harmonic self-mixer and is used for amplifying the quadruplicated frequency signal and outputting the amplified quadruplicated frequency signal. The signal source circuit can generate quadruplicated frequency signals.

The invention discloses a blood flow signal processing method and device based on silicon-based photons and wearable device.The method comprises the steps that firstly, phase modulation is conducted on three emitted narrow-band lasers with different wavelengths, the modulation frequency is set to be 50-100 MHz, and the generated sideband frequency is set to be 50-100 MHz; receiving a reflection signal passing through a human body artery blood vessel target area, demodulating the reflection signal and a local oscillator signal in a frequency mixer, and extracting a PDH error signal; finally, the blood flow direction in the target area is judged according to the positive and negative values. According to the hemodynamic monitoring system based on the optical resonant cavity array and the PDH read-out technology, through the innovation of a physical mechanism (strength detection is replaced by frequency detection), the innovation of a spatial architecture (an array replaces a single point) and the breakthrough of an algorithm model (physical field decoupling and waveform separation), the detection accuracy is improved; the problems that a traditional non-invasive blood pressure monitoring technology is low in precision, poor in interference resistance and lack of deep pathological information are fundamentally solved.

The invention provides a design method of an ultra-low phase noise frequency synthesizer based on regenerative frequency division. The design method comprises the following steps: step 1, enabling a source frequency to generate a multiple frequency through a frequency multiplier; step 2, inputting the multiple frequency into a two-way power divider, and generating an excessive frequency 1 through a phase-locked loop 1 by one path of output of the two-way power divider; the other path of output of the two-way power divider generates an excessive frequency 2 through a phase-locked loop 2; 3, the transition frequency 1 passes through a digital frequency divider and a regeneration frequency divider in sequence to generate transition frequency 3; and step 4, inputting the transition frequency 2 and the transition frequency 3 into a frequency mixer for frequency mixing, and then processing through a filter and an amplifier again to generate a target frequency. When the circuit topology and the transition frequency are designed, how to reduce the phase noise index is considered. According to the design method, the low-phase noise characteristic of the regenerative frequency divider is fully utilized.

A radio-frequency (RF) chip includes a mixer configured to mix a local oscillation signal with a baseband signal to output an RF signal, an amplification stage configured to amplify the RF signal through a plurality of unit amplifiers operating in response to a first control signal, and a compensation capacitor bank provided between the mixer and the amplification stage. The compensation capacitor bank is configured to adjust a capacitance of the compensation capacitor bank based on a second control signal, the second control signal being complementary to the first control signal.

The invention provides a WiFi network digital down-conversion system which comprises a multi-phase mixer and a resampling filter. The multi-phase mixer is used for converting a high-speed digital band-pass signal into a low-speed mode so as to realize digital down-conversion (DDC) on an FPGA (Field Programmable Gate Array) platform; and the resampling filter is used for reducing the sampling rate and removing unwanted frequency spectrum components to generate a complex baseband frequency spectrum. The multi-phase mixer PM of the present invention employs a parallel coordinate rotation digital computer (CORDIC) processor and a low pass filter array to reduce high speed data rates while minimizing resource utilization. The resampling filter comprises a cascade integral combination (CIC) filter and a multi-channel pulse finite impulse response (FIR) filter, optimal hardware cost is achieved, a floating point data type is converted into a fixed point data type, and resources are remarkably saved.

A nuclear magnetic resonance sensor applies a high frequency magnetic field based on an RF signal to a target and generates an observation signal with a frequency shifted from that of the RF signal by a frequency of an NMR signal. A mixer generates an IF demodulation signal including the NMR signal. A low-pass filter passes a low frequency component of the IF demodulation signal. In a digitizing device, a physical field generator generates a magnetic field corresponding to the IF demodulation signal passed through the low-pass filter, an optical quantum sensor generates light corresponding to the magnetic field by a sensing member and converts the light into a sensor signal by a photoelectric element, and an analog / digital converter digitizes the sensor signal. The optical quantum sensor performs a quantum operation on the sensing member and causes the sensing member to generate the light corresponding to the magnetic field.

The present invention belongs to the technical field of terahertz mixer testing, and relates to an efficient test method and test system for millimeter-wave terahertz mixers. The test system comprises a vector network analyzer and terahertz S-parameter test modules. On the basis of different radio frequencies and local oscillator frequencies caused by the mixing order of a mixer under test, test platforms having two structures are provided, wherein a first-type test platform comprises a vector network analyzer, and a first terahertz S-parameter test module and a second terahertz S-parameter test module that are connected to the vector network analyzer; and a second-type test platform comprises a vector network analyzer and a terahertz S-parameter test module connected to the vector network analyzer. The test method provided by the present invention implements efficient testing of terahertz-band mixers on the basis of combining a microwave-band vector network analyzer main unit with terahertz S-parameter test modules, and solves the problems of low test efficiency, complicated test processes and high costs of existing terahertz mixers.