1046 results about "Frequency mixer" patented technology

This disclosure describes an auto-calibration of mixers in a quantum orchestration platform. Predistortion is computed according to an RF signal that is downconverted with a local oscillator tone that is offset from an upconverter tone. Three tones present in the original RF signal are distinguished and used to construct a cost function. The minimization of the cost function is used to cancel an unwanted LO leakage and an image tone. Because the quantum orchestration platform generates both the unconverted IQ signals and the cost function for their optimization, the optimization can be performed in real time inside a single device without the need to communicate with external devices. This allows for the optimization of single sideband upconverted signals in a fraction of the time it typically takes using distributed systems employing separate waveform generators and spectrum analyzers.

The invention discloses a high-throughput satellite communication terminal system, which comprises a radio frequency channel unit, a signal processing unit, a terminal processing unit, a power supply management unit and an anti-electromagnetic interference module, and is characterized in that the radio frequency channel unit carries an agile device and a power amplifier and is used for realizing bidirectional conversion between a baseband signal and a radio frequency signal; communication frequencies of a Ka frequency band, a valley value of 5GHz and a peak value of 40GHz are supported, a zero intermediate frequency receiver structure is adopted, image frequency interference is eliminated through one-time frequency conversion to a baseband, and a high-integration design that a radio frequency signal directly enters a frequency mixer after passing through an antenna, a radio frequency filter and a low-noise amplifier is realized. According to the high-throughput satellite communication terminal system, the coverage problem of traditional communication in a blind area of a power grid is solved, safe, efficient and stable transmission of power data is realized, the emergency communication capability and the equipment environment adaptability are remarkably improved, and key technical support is provided for constructing global visual monitoring and intelligent scheduling of the digital power grid.

The invention relates to the technical field of signal detection, in particular to a weak electric field signal detection method and system. According to the invention, complete information of frequency, amplitude and phase of a to-be-measured electric field signal is obtained at the same time in one measurement of the injection locking phonon laser, a to-be-measured laser amplitude spectrum and a to-be-measured laser phase spectrum are generated by the same injection locking phonon laser, and the amplitude signal and the phase signal which are measured and received must arrive at the same time. The two are simultaneous in time and have natural orthogonality in physics; therefore, compared with a traditional double-phase lock amplifier for analyzing two asynchronous signals to be measured received by two frequency mixers, the method for analyzing the laser amplitude spectrum and the laser phase spectrum to be measured to obtain the electric field information to be measured has the advantages that the accuracy is higher; the double-phase lock amplifier solves the technical problem of measurement errors caused by deviation of to-be-measured signals received by two frequency mixers in a traditional double-phase lock amplifier.

The invention provides a microwave superheterodyne frequency sweep measurement system based on Rydberg atoms, and belongs to the technical field of microwave frequency measurement. The laser module excites detection light of 780 nm and coupling light of 480 nm, and the two beams of light are reversely input into the atomic gas chamber through the dichroscope; signal microwaves are generated by a radio frequency signal source and are radiated to the position of the atomic gas chamber through the horn antenna; local oscillation microwaves are generated by the microwave module and are also radiated to the position of the atomic gas chamber through the horn antenna; the atomic gas chamber serves as a mixer to form a difference frequency signal; the spectrum analyzer is used for monitoring low-frequency difference frequency signals generated in the frequency mixing process in real time and recording signal intensity in real time. According to the invention, high-precision and wide-band microwave frequency measurement is realized, continuous and smooth frequency sweeping response can be provided in a frequency range, and absolute frequency detection of microwave signals is realized under the condition that a complex frequency comb technology is not introduced. The hardware architecture is simplified, the automation degree is improved, and integration, popularization and application are facilitated.

The invention discloses a frequency measurement circuit and a frequency measurement method, belongs to the technical field of frequency measurement, and mainly solves the problems that the existing frequency measurement is large in frequency error, low in frequency measurement speed and narrow in frequency measurement bandwidth, and cannot meet the requirements of radar communication. The frequency measurement circuit comprises an FPGA control module, a reference clock circuit connected with the FPGA control module, a DDS frequency output circuit, a phase discrimination frequency control circuit, a frequency mixer connected with the phase discrimination frequency control circuit, and a radio frequency input circuit connected with the frequency mixer. According to the frequency measurement technology, the DDS output frequency is directly collected according to the characteristic that the FPGA collects the low frequency, the DDS output frequency serves as the phase discriminator phase discrimination frequency, frequency measurement is conducted in a phase locking mode, and the frequency measurement precision is high; the phase discriminator is set to have a fixed frequency dividing ratio, the phase discriminator is configured with a fixed register, a DDS frequency sweeping mode is adopted, and the frequency measurement time is short by changing the phase discrimination frequency of the phase discriminator to the output frequency of the phase-locked loop; and the frequency measurement bandwidth is increased by using a radio frequency input frequency division mode.

The invention provides a signal transceiving test system for simulating a shared local oscillator and a calibration method thereof, and the system comprises a signal generation module which outputs a baseband signal; the first local oscillator module comprises a first clock source, a first phase-locked loop and a first frequency multiplication channel, and the first frequency multiplication channel outputs a first local oscillator signal; the first frequency mixer is used for mixing the baseband signal and the first local oscillator signal to generate a modulation signal; the second local oscillator module comprises a second clock source, a second phase-locked loop and a second frequency multiplication channel, and the second frequency multiplication channel outputs a second local oscillator signal; the second frequency mixer is used for mixing the modulation signal and the second local oscillation signal to generate a demodulation signal; the signal analysis module is used for receiving and analyzing the demodulated signal; and the controller adjusts the first phase-locked loop or the second phase-locked loop. The problem that the phase difference of different local oscillators cannot be predicted can be solved while mutual interference of the shared local oscillators is avoided, so that the test calibration precision is improved.

A system may include a digital front end (DFE). The DFE may be configured to generate a command signal. The system may also include a sweeper. The sweeper may be configured to generate an intermediate in-phase signal, an intermediate quadrature signal, and a LO signal based on the command signal. In addition, the system may include a mixer. The mixer may be configured to generate a mixed in-phase signal based on the intermediate in-phase signal and the LO signal. The mixer may also be configured to generate a mixed quadrature signal based on the intermediate quadrature signal and the LO signal. Further, the system may include an amplifier. The amplifier may be configured to generate an in-phase signal based on the mixed in-phase signal and an amplification setting. The amplifier may also be configured to generate a quadrature signal based on the mixed quadrature signal and the amplification setting.

The invention provides a GEO communication satellite uplink signal Doppler frequency compensation method and device. The method comprises the following steps: acquiring a satellite orbit determination result corresponding to a GEO communication satellite; determining a Doppler compensation frequency curve according to the satellite orbit measurement result and the local frequency of the frequency conversion of a satellite transponder configured in the GEO communication satellite; and compensating a first uplink signal to be transmitted from the ground station to the GEO communication satellite by using the Doppler compensation frequency curve through the compensation frequency mixer, and transmitting the compensated first uplink signal to the GEO communication satellite. According to the invention, under the condition that the user receiver is non-inductive, the carrier frequency and the spreading code rate of the user receiver are changed in equal proportion, so that the user receiver can adopt a receiving algorithm of the carrier-assisted spreading code rate to improve the sensitivity.

The invention discloses a microwave reflectometer system. An arbitrary waveform generator generates a microwave signal through an X-Ku signal source unit; the coaxial directional coupler divides the generated microwave signal into two paths, one path enters the transmitting unit, and the other path enters the reference unit; a microwave signal entering the transmitting unit is transmitted into the plasma through a fundamental mode rectangular waveguide in the transmitting circuit; the microwave signal entering the reference unit is subjected to flight time compensation through a delay line and then is mixed with a reflected signal received by the receiving unit in a balanced mixer; the calibration unit carries out secondary frequency mixing on the dispersion calibration voltage-time curve signal and the signal obtained after primary frequency mixing of the balanced frequency mixer so as to eliminate dispersion interference; the acquisition card acquires an output signal after secondary frequency mixing of the calibration unit. The system can be integrated with an ion cyclotron resonance antenna, the inherent defects of large attenuation and high dispersion of a long-distance fundamental mode waveguide are overcome, and a high-frequency fundamental mode waveguide through-wall scheme meeting ultrahigh vacuum performance index requirements is realized.

A mixer includes a mixing stage, and a first transistor and a second transistor coupled to the mixing stage. A gate of the first transistor is coupled to a first input of the mixer, and a gate of the second transistor is coupled to a second input of the mixer. The mixer also includes a first source resistor coupled to a source of the first transistor, and a second source resistor coupled to a source of the second transistor. The mixer further includes an amplifier having a first input coupled to the source of the first transistor, and a second input coupled to the source of the second transistor. The amplifier is configured to adjust at least one bias voltage of at least one of the first transistor and the second transistor based on a differential voltage between the first and second inputs of the amplifier.

The invention provides an automatic gain control system and method based on radio frequency envelope detection, and a receiver. The bias end of an LNA is connected with an automatic gain control module; an envelope detection circuit is also connected between the output end of the LNA and the frequency mixer, and the envelope detection circuit is connected with an automatic gain control module; the detection module is used for outputting a preset level saturation indication signal to the automatic gain control module when an input signal which comes from the output end of the LNA and is greater than preset power is detected; the control end of the VGA is connected with the automatic gain control module; the output end of the ADC is connected with the automatic gain control module; the automatic gain control module performs automatic adjustment of receiver link gain. The fast envelope detection provides extra information, the automatic gain control response speed of the system is improved, the circuit design is simple, the power consumption is smaller, only a smaller chip layout area is occupied, and the cost is lower.

The invention discloses an optical fiber signal transmission system and method based on quantum noise encryption, and relates to the technical field of optical fiber communication, and the system comprises a composite modulation transmitting module, a dispersion compensation relay module, a coherent receiving module and a digital signal processor. The composite modulation transmitting module comprises an electro-optical modulator and a quantum noise randomization encoder; the dispersion compensation relay module comprises an adjustable dispersion compensator and a Raman amplifier; the coherent receiving module comprises a local oscillator laser and a 90-degree optical mixer; a digital signal processor includes a clock recovery unit and a maximum likelihood sequence detector. All the modules are sequentially connected and cooperatively work. And the adjustable dispersion compensator dynamically applies reverse dispersion compensation calculated based on a dispersion coefficient and a transmission distance according to the dispersion amount monitored in real time. According to the invention, through technologies of quantum noise encryption, dynamic dispersion compensation, Raman amplification, coherent reception and the like, safe and efficient transmission with single-wave 400Gbps and 100km transmission bit error rate less than or equal to 1 * 10 <-12 > is realized.

The photonic integrated chip comprises a substrate, a demultiplexer and a light guide assembly, and the light guide assembly and the demultiplexer are integrated on the substrate; the light guide assembly comprises a first light splitting coupler, a second light splitting coupler and a frequency mixer, and the first light splitting coupler is in optical communication connection with the output end of a corresponding channel of the demultiplexer so as to allow the demultiplexer to transmit an optical signal to the first light splitting coupler; the first light splitting coupler is used for splitting a received optical signal into local oscillation light and signal light, and the first light splitting coupler is in optical communication connection with the second light splitting coupler and the frequency mixer so as to allow the first light splitting coupler to transmit the local oscillation light to the frequency mixer and transmit the signal light to the second light splitting coupler; the second light splitting coupler is used for transmitting the signal light to a detection object and receiving echo signal light fed back by the detection object, and the second light splitting coupler is in optical communication connection with the frequency mixer so as to allow the second light splitting coupler to transmit the echo signal light to the frequency mixer.

The invention discloses a DP-MZM-based reconfigurable mixer with phase shift and image rejection functions, and belongs to the field of microwave photon signal processing. By adjusting an input radio frequency signal and a direct current bias voltage of the DP-MZM1, four different LO frequency doubling and mixing functions can be realized. By controlling the angle alpha between the polarization direction of the polarization analyzer and one axis of the modulator, the phase of the generated signal can be flexibly tuned in the range of 0-360 degrees. When combined with the optical frequency comb, the multi-channel multi-band frequency conversion system can be expanded into a multi-channel multi-band frequency conversion system with independent phase tuning capability by utilizing the channel switching and frequency slot selection functions of the wavelength selection switch, and parallel output of various frequency mixing results can be realized. By adjusting the phase difference between the two-channel output signals, I / Q mixing, double-balanced mixing and image rejection mixing can be configured. The scheme is not influenced by direct current bias drift, the system complexity is reduced, and the frequency conversion efficiency is improved.

The invention discloses a voltage transformer insulation state evaluation and dielectric self-repairing method and system. The method comprises the steps that a quantum dot array sensor is embedded in the surface of a voltage dividing capacitor unit of a CVT to obtain the capacitance value of a CVT insulation layer; a high-frequency scanning signal is injected into an end screen input port of the CVT, a local oscillator and a quantum mixer are arranged at an output port, and a dielectric loss factor is obtained; carrying out circuit analysis on the CVT insulation circuit, converting an insulation layer capacitance value and a dielectric loss factor into a capacitor breakdown number and a dielectric loss abnormal characteristic parameter, respectively taking the parameters as inputs of a WOA-based optimized DBA model, and obtaining a capacitor breakdown error variable quantity and a dielectric loss error variable quantity; and when the capacitance breakdown error variable quantity or the dielectric loss error variable quantity is not 0, judging that the insulation state of the CVT is abnormal, and triggering a self-repairing material feedback control mechanism. According to the invention, on-line evaluation of the internal insulation state of the CVT is realized by on-line monitoring whether the capacitor of the CVT is broken down and whether the dielectric loss is abnormally increased.

A receiver includes an antenna block configured to transduce impinging electromagnetic signals into electrical signals; a signal conditioning block configured to condition electrical signals received from the antenna block; and a down-converter block configured to down-convert conditioned electrical signals received from the signal conditioning block. The down-converter block comprises a plurality of signal channels. The receiver further includes a plurality of analog-to-digital converters (ADCs) respectively connected to the signal channels of the down-converter block; and a field-programmable gate array (FPGA). The FPGA is configured to program the down-converter block by selecting a set of mixer frequencies and a set of bandwidths designed to remove interference signals in each signal channel. The selections are calculated to mitigate reductions in dynamic range in the ADCs due to interference. The FPGA is further configured to process digital signals received from the ADCs after the down-converter block has removed the interference signals.

The invention discloses a frequency modulation continuous wave radar multi-target dynamic separation and anti-interference method and system based on synchronous extraction transformation, and the method comprises the steps: S1, generating a linear frequency modulation continuous wave, and transmitting a high-frequency signal through a radio frequency front end; s2, receiving a target reflection signal, mixing the target reflection signal with the emission signal through a mixer, extracting an intermediate frequency beat signal, and performing denoising; s3, performing time-frequency decomposition on the signal by adopting synchronous extraction transformation to generate a high-resolution time-frequency distribution matrix; s4, separating overlapped targets based on the time-frequency matrix by adopting a density clustering algorithm, eliminating a distance-speed coupling error in combination with a dynamic decoupling compensation algorithm, and outputting a time-frequency track of an independent target; constructing a dynamic time-frequency domain mask filter to filter noise, and optimizing the detection sensitivity and performing false alarm control through an adaptive threshold detection mechanism; according to the method, dense targets are accurately separated through high-resolution time-frequency analysis, and the anti-interference capability and the dynamic target tracking precision are improved in combination with a dynamic Doppler decoupling algorithm.

The invention relates to a 92GHz MIMO roadside radar radio frequency system based on a frequency conversion assembly, and the radar radio frequency system comprises a baseband processing layer which comprises at least two cascaded millimeter wave system-level SoC chips; the frequency conversion layer is a frequency conversion module FCM, and the FCM comprises a local oscillator synthesis unit, an upper mixer group and a lower mixer group; the local oscillation synthesis unit is used for generating a 13GHz local oscillation signal; the input end of the upper mixer group is connected with the output end of the baseband processing layer, the local oscillation end of the upper mixer group is connected with the local oscillation synthesis unit, the output end of the lower mixer group is connected with the input end of the baseband processing layer, and the local oscillation end of the lower mixer group is connected with the local oscillation synthesis unit; and the down-conversion layer is used for down-converting 92-94 GHz echo signals received by the antenna array to 79-81 GHz and then outputting the echo signals to the baseband processing layer. According to the invention, 92-94 GHz frequency conversion can be realized.

An integrated photonics millimeter wave (MMW) radar communication system based on analog phase modulation scheme includes an integrated photonics MMW radar communication signal transmitter, a radar receiver, and a communication receiver. The transmitter includes a radar communication signal analog phase modulation module, an optical frequency comb (OFC) module, an electro-optic modulator (EOM), an optical shaping filter, an optical power divider, a photoelectric detector, an electric power amplifier, and a transmitting antenna that are cascaded sequentially. The radar receiver includes a radar receiving antenna, an electric low-noise amplifier (LNA), an optical phase modulator, an optical bandpass filter (BPF), a low-speed photoelectric detector, an electric low-pass filter, and a low-speed oscilloscope that are cascaded sequentially. In the communication receiver, a communication receiving antenna is sequentially cascaded with an electric LNA, a frequency mixer, and an oscilloscope, and a voltage-controlled oscillator is cascaded with a frequency multiplier and then connected to the frequency mixer.

The invention provides a vehicle suspension control method and a vehicle suspension control system, the control method is applied to the vehicle suspension control system, and the vehicle suspension control system comprises a frequency mixer used for determining a frequency demarcation point based on vehicle state data; the ceiling controller is used for determining ceiling suspension active force based on the vehicle state data and the frequency demarcation point; the ground shed controller is used for determining the main power of a ground shed suspension based on the vehicle state data and the frequency demarcation point; the fusion device is used for determining a target suspension active force based on the ceiling suspension active force and the ground ceiling suspension active force; the target suspension active force is used for controlling the vehicle suspension. Therefore, when the vehicle state data is changed, the frequency demarcation point is also changed, the dynamic real-time fusion of the sky and ground shed control strategy can be realized, and the smoothness and the operation stability are both considered; and the frequency demarcation point dynamically adjusts the fusion weight, and the adjustment process is continuous and non-step, so that smooth transition can be realized.

The utility model discloses a miniaturized image rejection frequency mixing circuit, which comprises two passive double-balanced frequency mixers, a local oscillator bridge, a phase shift circuit and a power divider, the first input ends of the first passive double-balanced mixer and the second passive double-balanced mixer are connected with an external antenna; the second input end of the first passive double-balanced mixer is connected with the first output end of the local oscillator bridge, the second input end of the second passive double-balanced mixer is connected with the second output end of the local oscillator bridge, and the output end of the first passive double-balanced mixer is connected with the input end of the phase shift circuit. The output end of the second passive double-balanced mixer is connected with the second input end of the power divider; the isolation end of the local oscillator bridge is connected with the load resistor, and the input end of the local oscillator bridge is connected with the frequency source; the output end of the phase shift circuit is connected with the first input end of the power divider, and the output end of the power divider is connected with an external circuit. According to the utility model, the size of the image rejection mixer can be obviously reduced, and miniaturization design of a radar receiver is facilitated.

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.

One or more systems, devices and / or methods of use provided herein relate to a baseband filter that can be used in a current-mode end-to-end signal path. The current-mode end-to-end signal path can include a digital to analog converter (DAC) operating in current-mode and an upconverting mixer, operating in current-mode and operatively coupled to the DAC. In one or more embodiments, a device used in the signal path can comprise a baseband filter that receives an input current and outputs an output current. The baseband filter can comprise a feedback loop component having an active circuit branch and a passive circuit branch coupled in a loop. A mirroring device can be coupled to the feedback loop component and can provide an output of the device. Selectively activating the mirroring device can vary gain, such as of the mirroring device.

The utility model relates to the technical field of millimeter wave radio frequency communication, and discloses a broadband millimeter wave dual-channel receiver, which comprises two receiving links and a power divider, each receiving link is connected with the power divider, each receiving link comprises an isolator, a frequency mixer and an intermediate frequency amplifier which are sequentially connected from input to output, one input end of the frequency mixer is connected with a frequency multiplier, and the input end of the frequency multiplier is connected with one output end of the power divider; according to the utility model, mutual interference of multiple paths of signals in a test can be effectively prevented, two paths of millimeter wave radio frequency signals can be tested and analyzed at the same time, and the device can be used for various test scenes such as down-conversion test, two paths of radio frequency signal amplitude-phase consistency test, noise coefficient test and the like.

The invention relates to the technical field of terahertz signal receiving, in particular to a photo-generated local oscillator multi-band tuning millimeter wave mixing receiver device. The device comprises an antenna, a photo-generated local oscillator circuit, a broadband coherent frequency mixing circuit, a baseband signal processing platform, a PC control end and a time division multi-frequency tuning module. By introducing a photo-generated local oscillator technology, a millimeter wave local oscillator signal with high frequency, stability and low phase noise is obtained, and the adaptability of the system to multi-band and cross-band signals is improved. By adopting the broadband coherent odd harmonic mixer with the fin line structure, high-efficiency mixing of a radio frequency signal and a local oscillator signal is realized, and the broadband coherent odd harmonic mixer has the advantages of broadband, high-efficiency odd mixing, low loss, compact integration and the like. On the basis, a time division multi-frequency tuning technology is adopted, and dynamic tuning and switching of multi-frequency-band signals are achieved in a single receiving framework. According to the invention, the problems of frequency band switching bottleneck and multiplexing loss in a traditional multi-frequency receiving system are solved. The antenna has the advantages of being compact in structure, capable of covering multiple frequency bands, suitable for multi-frequency-band observation requirements in a high-sensitivity radiometer system and the like.

A hearing device includes: a pinna restorer for provision of a pinna output based on a first pinna input and a second pinna input, wherein the first pinna input is based on a primary first microphone input signal, and wherein the second pinna input is based on a primary second microphone input signal, the pinna restorer comprising: a first filter for provision of a first mixer input based on the first pinna input, a second filter for provision of a second mixer input based on the second pinna input, a first mixer for provision of a first mixer output based on the first mixer input and the second mixer input, and a pinna controller; and an input mixer for provision of an input mixer output based on the pinna output and a secondary mixer input, wherein the secondary mixer input is based on a secondary microphone input signal.

The invention relates to the technical field of laser radars, in particular to a non-aliasing frequency-modulated continuous wave radar detection system and method, and the system comprises a light source, a beam splitter, a circulator, a 90-degree mixer, a signal conversion module and a signal processing unit. The signal processing unit is configured to construct a composite vector signal S based on the first electric signal I and the second electric signal Q, S = I + jQ, j is an imaginary part operator, obtain a double-sideband spectrum based on the composite vector signal S, determine the frequency of a signal peak in an upper frequency sweeping period and the frequency of a signal peak in a lower frequency sweeping period in the double-sideband spectrum, and determine the frequency of the signal peak in the upper frequency sweeping period and the frequency of the signal peak in the lower frequency sweeping period; and obtaining the distance and speed of the target to be measured based on the frequency of the signal peak in the upper frequency sweeping period and the frequency of the signal peak in the lower frequency sweeping period. According to the invention, the problem of signal aliasing during detection of the to-be-detected target can be solved at least.

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.

An integrated photonic device independently directs each channel of a multiplexed input optical signal received from a corresponding one of N input port to one of N output ports, each multiplexed input optical signal including N channels. The device includes: N input waveguides; secondary waveguides; wavelength-selective filters, each: i) including a ring resonator, ii) being optically coupled to a corresponding one of the N input waveguides and a corresponding one of the secondary waveguides, and iii) being switchable between a first state in which an optical signal in a corresponding one of the N channels is coupled from the corresponding input waveguide into the corresponding secondary waveguide and a second state in which the optical signal in the corresponding one of the N channels is not coupled into the corresponding secondary waveguide; N multi-wavelength mixers; and N output waveguides.

The present invention discloses a radio frequency stealth method based on sidelobe power suppression of a subarray-level four-dimensional antenna array. The basic system of the method is composed of an antenna array, a radio frequency switch, a power divider, a signal source, a local oscillator source, a mixer, a power amplifier, a switch control system, a phase shifter, and an attenuator. Under the premise of considering the radiation pattern of the array antenna unit, the method is based on subarray division and array statistical performance, and achieves a low average radiation power effect in the sidelobe area through a low mean square value, so that the probability of signal detection is reduced. On this basis, the probability of the received signal being identified can be minimized in the non-desired direction by maximizing the relative variance. Compared with the existing confidentiality system, the physical structure of this method is simple and the calculation is convenient. The present invention is applied to wireless communication systems with high radio frequency stealth performance requirements.