286 results about "Frequency synthesizer" patented technology

A digital frequency synthesizer includes a delay-locked loop (DLL) that generates time-delayed versions of a reference clock signal, a clock divider that executes an integer-division operation on one delayed clock signal to generate an integer-divided clock signal, and control circuitry that generates fractional data for enabling a fractional division. The digital frequency synthesizer further includes a first clock selector that selects one delayed clock signal as a DLL clock signal based on the fractional data, a delay chain that generates time-delayed versions of the DLL clock signal, and a second clock selector that selects one delayed clock signal as a selected clock signal based on the fractional data. A rising edge of the integer-divided clock signal is adjusted based on the selected clock signal to generate a fractional-divided clock signal that is a fractional-divided version of the reference clock signal.

The invention relates to the field of digital signal processing, in particular to a miniature digital transceiver module which comprises a signal processing board and a power clock board. The signal processing board and the power supply clock board are stacked and interconnected through a high-speed connector; the signal processing board integrates multiple ADC acquisition channels and DAC output channels, and is internally provided with an RFSOC chip to realize multichannel digital down-conversion, waveform generation and signal processing functions. The power supply clock board integrates a power supply conversion module and a clock frequency synthesizer, provides various power supply varieties for the module, and generates a time sequence, a sampling clock and a reference clock. The stacking design of the two board cards forms a high-integration digital transceiver module, thereby saving a large amount of space and improving the system integration. The scheme is obviously superior to a traditional design method in the aspects of volume, power consumption, performance and the like, and is particularly suitable for equipment sensitive to an outer envelope.

The embodiment of the invention provides a rubidium atomic clock based on a velocity grating spectrum and an implementation method, and the method comprises the steps: enabling a multi-frequency coherent laser source to emit a laser signal containing the velocity grating spectrum, and dividing the laser signal into two paths through a polarization splitting prism; the reflected light beam enters the laser frequency stabilization module to realize laser frequency stabilization; a transmission light beam enters the rubidium bubble through the lens group to interact with rubidium atoms; the photoelectric tube detects a transition spectral line, converts the transition spectral line from an optical signal into an electric signal and transmits the electric signal to the lock-in amplifier for demodulation; the integral amplification module converts the demodulated direct-current voltage into linear increasing voltage and transmits the linear increasing voltage to the crystal oscillator; the crystal oscillator generates an initial microwave signal and generates a microwave signal corresponding to the 87Rb atom through the frequency synthesizer; and the phase frequency modulation module modulates the microwave signal to obtain an error signal and transmits the error signal to the microwave resonant cavity so as to adjust the electromagnetic field according to the error signal to stably lock the rubidium atomic clock. The method is used for achieving the effect of improving the stability of the rubidium atomic clock system.

A method and / or apparatus for tuning a frequency synthesizer device toward a prescribed frequency may input a signal into the input of the frequency synthesizer to produce an output signal having an output frequency, select a first one of a set of the above noted prescribed coarse curves, and compare the magnitude of the difference between the prescribed frequency and the output frequency. Next, the method selects a second of the set of coarse curves as a function of the magnitude of the difference between the prescribed frequency and the output frequency. Preferably, the method selects the second of the set of coarse curves by selecting one or more of the coarse curves out of the sequential frequency order as a function of the magnitude of the difference between the prescribed frequency and the output frequency.

The invention provides a programmable frequency control array radar waveform generation system and method based on an FPGA, and belongs to the technical field of radar systems and digital signal processing. In order to solve the technical problems of complex hardware system, inflexible parameter adjustment and poor multi-channel synchronism of the traditional frequency control array radar, the invention provides an integrated high-performance solution. The system adopts an FPGA (Field Programmable Gate Array) architecture of an integrated processing system (PS) and programmable logic (PL). The method comprises the following steps: a PS end receives waveform control parameters of an upper computer through a communication interface and transmits the waveform control parameters to a PL end; and a plurality of parallel direct digital frequency synthesizer (DDS) modules in the PL end synchronously generate multi-channel digital baseband signals with programmable frequency offset at high precision according to the parameters under the unified driving of the FPGA global clock network. And the digital signal is subjected to digital-to-analog conversion and radio frequency front-end processing to finally form a transmitting wave beam. According to the invention, flexible programmability of parameters is realized by utilizing a PS-PL collaborative architecture, the synchronization precision of multi-channel signals is remarkably improved through a global clock network and a parallel DDS module generated in the FPGA, and meanwhile, the system has the advantages of high integration level and low complexity.

The invention discloses an I / Q imbalance distortion suppression phase demodulation system based on carrier frequency closed-loop modulation. The I / Q imbalance distortion suppression phase demodulation system comprises an I / Q mixer, an I channel conditioning circuit, a Q channel conditioning circuit, an I channel analog-to-digital converter, a Q channel analog-to-digital converter, a direct digital frequency synthesizer and a microcontroller, the microcontroller comprises an arc tangent module, a carrier frequency generation module, a residual phase calibration module, a feedback control output module and a demodulation phase output module. According to the I / Q imbalance distortion suppression phase demodulation system based on carrier frequency closed-loop modulation, the target of closed-loop control is modified, and on the basis of tracking the phase of an input signal, the mixed signal is modulated on one frequency through feedback control, so that on one hand, the signal is separated from low-frequency noise, and on the other hand, the frequency of the signal is reduced; and on the other hand, the nonlinear harmonic is modulated on the carrier frequency, so that the amplitude of the nonlinear harmonic component is greatly reduced, low-frequency noise floor deterioration is avoided, and signal detection and extraction are facilitated.

The invention discloses a fractional frequency division frequency synthesizer with output signal phase synchronization and frequency modulation continuous wave functions, and the basic structure is a charge pump phase-locked loop. Comprising a phase frequency detector, a first charge pump, a second charge pump, a low-pass filter, a voltage-controlled oscillator, a first buffer, a second buffer, a two-frequency divider chain, an IQ undersampling circuit, a local oscillator generator, a programmable multimode frequency divider, a Delta-Sigma modulator (DSM), a first selector, a second selector, a third selector, a tracking phase accumulator, a numerical control oscillator, an accumulation phase difference register and an atan2 logic circuit. The device comprises a main phase control circuit, a phase adjusting circuit, an enabling control circuit, a waveform generator and a serial peripheral interface. The decimal frequency-division frequency synthesizer can be applied to a general-inductance integrated system, ensures that output signals provided by a plurality of decimal frequency-division frequency synthesizers are consistent in phase in a multi-channel radio frequency transceiving system adopting a multi-chip splicing mode, and can also be applied to the general-inductance integrated system as a sensing signal source; and the speed and the distance of an object can be quickly sensed by the high linearity and the quick chirp capability of an output signal. The decimal frequency division frequency synthesizer is applied to a linear frequency modulation continuous wave radar system, initial phase synchronization can be carried out firstly, then frequency continuous modulation is carried out, and measurement errors can be eliminated. In view of functional similarity of partial modules of the synchronous loop and the FMCW loop, such as a phase frequency detector, a charge pump, a voltage-controlled oscillator and the like, the modules can be shared, so that the power consumption and area cost of the system are remarkably reduced.

The invention discloses a multi-channel multi-band universal intermediate frequency receiving and processing device, which relates to the field of communication and comprises a switch, a splitter, a variable gain amplifier, a temperature compensation attenuator, an amplifier, a filter, a frequency synthesizer, a frequency mixer, a numerical control attenuator, an FPGA (field programmable gate array) processor and the like. The system has the advantages of miniaturization, low power consumption, low cost, high jump speed, multiple channels, multiple frequency bands, full localization, high environment adaptability and the like, and can meet the application requirements of various working scenes such as a fixed station, a vehicle-mounted station, an airborne station, a portable station and the like. Rapid frequency hopping, multiple frequency bands, multiple channels and 100% localization are the key of the invention. Through the multi-channel and multi-frequency-band design, a plurality of independent receiving channels can be realized, a plurality of intermediate frequency working frequency bands such as 70MHz, 140MHz and extended L frequency bands are supported at the same time, and the universality and the integration degree of the intermediate frequency receiving channels are remarkably improved.

The invention discloses a deformation rolling stone integrated road slope radar monitoring system and a detection method, and belongs to the field of radar detection, the deformation rolling stone integrated road slope radar monitoring system comprises a signal processing module, a multi-channel radio frequency module and an antenna array module, the multi-channel radio frequency module is connected with the signal processing module through a hardware line, and the antenna array module is connected with the signal processing module. The antenna array module is connected with the multi-channel radio frequency module through a hardware line; the signal processing module comprises a programmable main control chip, a data memory, an analog-to-digital converter and a direct digital frequency synthesizer, a line of the signal processing module is also connected with a camera, and the system also comprises a power supply module for supplying power to the signal processing module, the multi-channel radio frequency module and the camera. According to the deformation and rolling stone integrated road slope radar monitoring system and the detection method, deformation and rolling stone integrated monitoring is realized, two sets of equipment do not need to be arranged, the cost and the arrangement difficulty are reduced, early warning is reliable, the environmental adaptability is high, and the requirement for long-term field road monitoring is met.

A charge pump includes a DAC (digital-to-analog converter) configured to draw a first current and a second current from a first node and a second node, respectively, in accordance with a first logical signal, a second logical, and a B-bit control word; a common-gate amplifier configured to provide a path for charge transfer between the second node and a third node in accordance with a third logical signal; an integrating capacitor connected to the second node and configured to be either discharged by the DAC or charged by the common-gate amplifier in accordance with a fourth logical signal; and a low-impedance active load connected to the first node.

The invention relates to the technical field of signal generation, and discloses a signal generation system and method, and the system comprises a first signal generation module; the second signal generation module comprises an analog signal generation unit and a signal copying unit; the signal mixing module comprises an analog frequency mixing unit, a digital frequency mixing unit and a signal switching unit; the output end of the analog signal generation unit is connected with the input end of the analog frequency mixing unit; the first end of the signal copying unit is connected with the clock signal output end of the analog signal generating unit, the second end is connected with the mixing input end of the analog signal generating unit, and the third end is connected with the first end of the signal switching unit; the second end of the signal switching unit is connected with the output end of the analog frequency mixing unit, and the third end is connected with the input end of the digital frequency mixing unit. Therefore, a direct digital frequency synthesizer in the analog signal generation unit is calibrated when the clock signal is switched to, and spurious signals are eliminated based on a calibration result when the clock signal is switched to the analog local oscillator signal.

The invention discloses an intelligent dual-mode radar system based on a terahertz frequency band and an imaging method thereof, and relates to the field of terahertz radars, and the system comprises a transmitting module which supports the dynamic switching of a short-distance high-resolution mode and a long-distance low-power-consumption mode; the receiving module is used for receiving an echo signal reflected by the target of the transmitting module; the frequency synthesizer is used for generating adaptive frequency sweeping bandwidth and frequency sweeping time parameters according to a target distance requirement, and presetting at least two waveform modes; the self-adaptive signal processing unit is used for dynamically adjusting filtering parameters and gains according to a target distance working mode and outputting target imaging data; and the control module is used for realizing parameter configuration and mode switching of dual-mode cooperative work. According to the dual-mode radar collaborative architecture, collaborative work of short-distance high-resolution imaging and long-distance low-power-consumption detection can be achieved, the performance bottleneck of a traditional single-mode radar is solved, and the dual-mode radar collaborative architecture is suitable for efficient target detection and imaging requirements of diversified scenes.

The invention discloses a meteorological radar and an assembly method thereof, the meteorological radar comprises a radar main body, a servo assembly and an array antenna, the radar main body comprises a signal processing unit, a frequency synthesizer assembly, an intermediate frequency assembly, a power division assembly and a T / R assembly; the array antenna comprises a reflecting plate, a plurality of umbrella-shaped dipole antenna units and a feed network PCB (Printed Circuit Board), wherein a plurality of cross-shaped grooves are formed in the reflecting plate; each umbrella-shaped dipole antenna unit comprises a first radiation unit and a second radiation unit, the first radiation unit is inserted on the second radiation unit, and the first radiation unit and the second radiation unit are orthogonally engaged; the first radiation unit and the second radiation unit are inserted into the corresponding cross-shaped grooves. And the second radiation unit of each umbrella-shaped dipole antenna unit and the feed network PCB are integrally designed. Orthogonal installation of the first radiation unit and the second radiation unit is ensured through limiting of the cross-shaped groove, and the antenna assembling process is simplified.

The invention discloses an online cable fault detection device and calibration method based on broadband impedance spectroscopy, belongs to the technical field of cable fault detection, is used for cable fault detection, and comprises a direct digital frequency synthesizer DDS, a micro control unit MCU, an analog-to-digital converter ADC, four low-pass filters, two multipliers and an electromagnetic coupling device. The DDS is respectively connected with the MCU, the first low-pass filter and the second low-pass filter, and the analog-to-digital converter ADC is respectively connected with the MCU, the third low-pass filter and the fourth low-pass filter; the calibration process of the method includes obtaining a measured value of the cable reflection coefficient and a true value of the cable reflection coefficient. According to the invention, cable defects are monitored and positioning is realized during on-line operation of the cable, and the method is suitable for cables of various specifications and three-phase cables, has universality, and reduces the detection difficulty; the broadband impedance spectroscopy measurement precision is improved, the measurement error is reduced, and the cable fault defect positioning precision is improved.

The invention discloses a phased array radar and a low-altitude detection radar system, the phased array radar comprises a lower shell and an upper shell which are oppositely arranged in a first direction, the lower shell and the upper shell define a containing cavity, and the containing cavity comprises a first cavity located in the lower shell; the phased array radar further comprises a frequency synthesizer, a signal processing plate, a heat conduction plate, an air cooling mechanism, a plurality of TR assemblies, an antenna and an antenna housing. The frequency synthesizer is arranged in the first cavity. The signal processing plate is arranged in the first cavity and is compactly arranged with the frequency synthesizer in the second direction; the heat conducting plate is arranged in the first cavity and located on the side, facing the upper shell, of the signal processing plate, the heat conducting plate is attached to the frequency synthesizer and the signal processing plate, and a cooling pipe is embedded in the heat conducting plate; the air cooling mechanism is arranged in the containing cavity and used for supplying air to the heat conduction plate so as to cool the heat conduction plate. The antenna housing is arranged on the side, away from the lower shell, of the upper shell so as to cover the TR assembly and the antenna. Through the compact arrangement of the frequency synthesizer and the signal processing board, the size of the phased array radar can be greatly reduced, and the phased array radar is convenient to carry and deploy.

The utility model discloses an anti-interference radio frequency device, and relates to the technical field of radio frequency devices. Comprising an antenna array, an anti-interference processing unit connected with the antenna array through a down-conversion channel and a straight-through channel, an up-conversion channel connected with the anti-interference processing unit, and a clock unit respectively connected with the down-conversion channel, the anti-interference processing unit and the up-conversion channel. Two radio frequency chips are connected between the down-conversion channel and the anti-interference processing unit and between the straight-through channel and the anti-interference processing unit. According to the anti-interference radio frequency device, the two radio frequency chips with four independent down-conversion receiving channels are adopted, an original frequency synthesizer unit is omitted, and the reliability of the device is improved; four channels are supported to receive radio frequency signals of the same frequency point at the same time, an anti-interference array receiver is formed, clock signals generated by a radio frequency chip can be multiplexed, under the same size, the size is reduced, the power consumption is reduced, the anti-interference performance is remarkably improved, the use requirement of product development is met, and good market popularization prospects are achieved.

A temperature-control-free double-optical-comb repetition frequency and phase digital locking system comprises a double-optical-comb light source module, a phase digital locking module, a phase setting module, a first controllable direct digital frequency synthesizer and a second controllable direct digital frequency synthesizer, the repetition frequency and phase of the double optical combs are locked through reference signals generated by the controllable direct digital frequency synthesizer, the frequency of the reference signals output by the controllable direct digital frequency synthesizer is adjusted through feedback signals of the first servo controller and the second servo controller when the temperature changes, and frequency and phase locking of the double optical comb optical system is achieved. Reference signal phases generated by the first controllable direct digital frequency synthesizer and the second controllable direct digital frequency synthesizer are controlled through the upper computer, respective control over the two optical comb pulse phases is achieved, a temperature control module is not needed in the system, the complexity of the system is reduced, and the stability and the integration degree of the system are improved.

The invention discloses a high-precision vector regulation and control device and method for a signal generation link, and belongs to the technical field of information. A frequency mixing feedback loop is adopted to replace a traditional ALC detection loop, the amplitude of a signal can be stabilized, the phase of the signal can also be stabilized, and impedance matching of a channel can also be regulated and controlled; a path feedback signal is converted into a digital signal for high-speed transmission, and the ADC, the signal processing module and the DDS are interconnected through a high-speed bus, so that high-speed vector regulation and control can be quickly performed, and the loop control speed is higher; according to the invention, the direct digital frequency synthesizer is in a loop, which means that the amplitude and phase drift in the DDS can also be captured by the loop for correction; according to the method, vector information of the amplitude and phase drift of the channel can be obtained at the same time, so that closed-loop dual control, namely vector control, is carried out, and the purpose of regulating and controlling the amplitude and phase of the signal at the same time is achieved.

The utility model discloses interference source equipment. Comprising a power control subsystem for realizing signal receiving and transmitting and power dynamic management, an intermediate frequency signal processing subsystem for realizing high-speed signal acquisition and playback, a main control subsystem for realizing system control, man-machine interaction and data processing, and an air feed subsystem for realizing radiation and receiving of electromagnetic signals, the power control subsystem comprises a signal receiving module used for receiving and transmitting communication signals, a transmitting channel module and a frequency synthesizer module, and the frequency synthesizer module integrates a voltage-controlled constant-temperature crystal oscillator, provides stable clock signals and simultaneously comprises external reference clock access and Beidou time synchronization; through integration of the power control subsystem, the intermediate frequency signal processing subsystem, the main control subsystem and the air feed subsystem, the volume and the weight are reduced, an individual soldier is convenient to carry, and the strategic significance of the utility model is increased.

The present disclosure provides an apparatus for wireless communications. The apparatus includes one or more processors; a transmit path coupled to the one or more processors comprising: a first frequency synthesizer configured to consume a first amount of power, wherein the first frequency synthesizer is configured to feed a first local oscillator (LO) signal that comprises a first frequency tone with a first phase noise profile; and a feedback receive path selectively coupled to the transmit path comprising: a second frequency synthesizer configured to consume a second amount of power less than the first amount of power, wherein: the second frequency synthesizer is configured to feed a second LO signal that comprises a second frequency tone with a second phase noise profile; the second frequency tone is offset from the first frequency tone; and the second phase noise profile comprises a wider phase profile than the first phase noise profile.

Systems and methods for digital signal synthesis with variable sample rate digital-to-analog converters (DACs) in accordance with embodiments of the invention are described. One embodiment includes a digital frequency generator that includes a direct digital frequency synthesizer (DDFS); a digital-to-analog converter (DAC); a frequency / phase estimation circuit; a stable reference clock (REF CLK); a variable frequency sample clock; a frequency control word (FCW); where the DAC is sampled by the variable frequency sample clock; where the DDFS is clocked by the variable frequency sample clock; where the frequency / phase estimation circuit receives a the stable REF CLK and the variable frequency sample clock and estimates a FCW frequency error and adjusts the FCW to the DDFS; where the DDFS receives the FCW and outputs a digital sine codeword at the variable frequency sample clock to the DAC, where the FCW is continuously adjusted to track the variable frequency sample clock.

The invention relates to the technical field of sonar emission signal source systems, in particular to a sonar emission signal source system based on a DDS and a working method. Comprising an ARM end, a main control circuit and a transmitting circuit, the ARM end is connected with the main control circuit, the main control circuit is connected with the transmitting circuit, the ARM end issues a working parameter instruction to the main control circuit, the main control circuit generates a corresponding waveform signal after receiving and analyzing the instruction, and the waveform signal is filtered through the transmitting circuit; the working parameters sent by the ARM end comprise center frequency, bandwidth and pulse width; the main control circuit uses an FPGA (Field Programmable Gate Array) as a main controller, the FPGA main control circuit adopts an XC6SLX16 / 25-2FTG256 chip, and the FPGA main control circuit is also connected with a 50MHz clock crystal oscillator, a serial SPI (Serial Peripheral Interface) configuration chip, a low-dropout voltage-stabilizing chip and a JTAG (Joint Test Action Group) interface; and the low-dropout voltage-stabilizing chip provides voltage for the system. A direct digital frequency synthesizer (DDS) technology is used, corresponding single-frequency signals or LFM signals can be generated according to received instructions of parameters such as frequency, bandwidth and pulse width of a working center, and application requirements of special occasions are met.

The present invention belongs to the field of radio communication, and specifically relates to a frequency synthesizer, comprising a reference signal generating circuit, a main phase-locked loop, a local oscillator signal generating circuit and a first power divider, wherein the reference signal generating circuit is respectively connected to the main phase-locked loop and the local oscillator signal generating circuit through the first power divider, and the main phase-locked loop is connected to the local oscillator signal generating circuit. The present invention has the function of reducing phase noise while generating a high-frequency frequency source.

The invention discloses a communication signal blind identification and parameter estimation system, which belongs to the technical field of signal analysis and comprises a receiver front end, a microwave down-conversion unit, a frequency synthesizer unit, an intermediate frequency signal processing unit, a computer processing unit and system control software. According to the method, blind identification and parameter estimation of nine communication signals in a complex electromagnetic environment can be accurately and quickly realized through design of software and hardware processing flows of the system, including AM, FM, BPSK, QPSK, OQPSK, 8PSK, FSK, MSK and QAM16, the code rate range can cover 1kHz-5MHz, the average identification accuracy can reach more than 95%, and the average estimation error of parameter estimation is less than 2%; through engineering verification, the method is easy to implement, high in speed and good in flexibility.

The invention discloses a broadband LFM signal array beamforming method and system thereof, belonging to the technical field of radar signal processing. The method comprises: antenna array elements of M channels receive radar echoes and receive the same mixing signal sent from the same digital frequency synthesizer; digitally mix the radar echo and the mixing signal of the first channel, filter out high-frequency components, and perform AD sampling on the mixing signal as a reference signal; digitally mix the mixing signal and the radar echo of the mth channel, perform low-pass filtering, and perform AD sampling to obtain a sampled signal m; input a mixing compensation signal into the mth channel, perform secondary digital mixing on the sampled signal m and the mixing compensation signal to obtain a secondary mixing signal m; apply a delay signal to each secondary mixing signal m to perform delay compensation, so that the output signal of the mth channel is equal to the reference signal; and accumulate the output signals of the M channels to obtain a de-skewed array beam.

The invention provides a radio frequency power supply output frequency calibration method and device. The method comprises the following steps: determining a current frequency output state and environmental parameters of a radio frequency power supply; inputting the current frequency output state and the environmental parameters into a frequency regulation model to obtain a regulation coefficient of a frequency register in a digital frequency synthesizer of the radio frequency power supply output by the frequency regulation model, regulating the frequency register based on the regulation coefficient of the frequency register, and regulating the frequency register based on the current actual output frequency of the radio frequency power supply. And updating the current calibration output frequency, repeatedly calling the above steps based on a comparison result of the current calibration output frequency and the target frequency to realize iterative calibration of the output frequency of the radio frequency power supply, and performing output frequency adjustment by using a frequency adjustment model in a training stage based on a calibration strategy learned by a specially designed behavior reward value. Accurate, efficient and stable output frequency calibration for the radio frequency power supply is realized.

This invention discloses a multi-level collaborative SAW exhaled breath detection system and method based on a large language model, belonging to the field of SAW detection technology. The system includes a precision RF excitation control layer, an IoT gateway layer, and a cloud-based AI analysis layer. Data interaction between the three layers is achieved through a heterogeneous communication protocol stack. The precision RF excitation control layer includes a microcontroller, a DDS frequency synthesizer, and an SAW resonator; the microcontroller has a built-in pre-verification module. The IoT gateway layer includes a dual-core processor, a wireless communication module, and an I / O interface. 2 The system features an S-channel audio interface and a dual-core processor with a heterogeneous architecture. The cloud-based AI analysis layer includes speech recognition services, large language model inference services, a utility function definition library submodule, and a command string generation submodule. The system has an end-to-end device-level mapping channel from user speech to the DDS frequency synthesizer's frequency tuning word register. This invention lowers the operational threshold for precision SAW inspection and adapts to on-site inspection scenarios.

The application discloses a microwave photon frequency hopping signal generation device and method based on an optical switch and belongs to the technical field of optical communication. The application is composed of a light source, a beam splitter, an optical frequency comb generator, an electro-optical frequency shifter, an acousto-optic modulator, a digital frequency synthesizer, a filter array, a signal control unit, an electrically controlled high-speed optical switch, a beam combiner and a photoelectric detector. The application separates optical frequency comb teeth by using an ultra-narrow bandwidth optical filter, selects and opens the frequency hopping signal generated by the local light beat frequency through the optical switch, and can generate a high-speed high-order high-stability frequency hopping signal compared with the prior art.

The present application relates to a frequency synthesizer with dynamically selected level shifting of an oscillating output signal. An oscillator circuit powered by a source voltage generates an oscillating output signal. The oscillating output signal is level shifted and applied to a first input of a multiplexer. A second input of the multiplexer receives the oscillating output signal. The multiplexer selects one of the oscillating output signal and the level shifted oscillating output signal to output as a selected oscillating output signal in response to a selection signal. A lock loop circuit controls a frequency of the oscillating output signal based on the selected oscillating output signal and a reference oscillating signal. The selection signal also selects one of the source voltage of the oscillator circuit and a reference voltage as an error amplifier reference voltage for a voltage regulator circuit that generates a first supply voltage.

The invention discloses an anti-interference radio frequency transceiving assembly which comprises a plurality of B1 low-noise amplification units, a B1 array antenna, a plurality of B3 low-noise amplification units, a B3 down-converter, a BDS B1 / GPS L1 down-converter, a first frequency synthesizer, a second frequency synthesizer, a crosslinking equipment digital signal processing board, a BDS B1 / GPS L1 up-converter, a B3 up-converter, a B2B low-noise amplifier unit and an S low-noise amplification unit. And the first triplexer is in data connection with the L power amplifier unit, the B2B, S and L three-in-one antenna array, the first directional coupler and the first logarithmic detector. According to the invention, electromagnetic wave signals of multiple paths of B3 and multiple paths of BDS B1 / GPS L1 are converted into electric signals, and the signals are filtered and amplified, so that amplitude-phase consistency is satisfied. And performing up-conversion on the analog intermediate frequency signal processed by the cross-linked digital signal processing board to output BDS B3 and BDS B1 / GPS L1 radio frequency signals. And the short message integrated service digital network can be realized.