613 results about "Intermodulation" patented technology

Aspects of the subject disclosure may include, for example, detecting an interference signal in two or more signals received via orthogonally-polarized elements of an antenna system, the interference signal originating from a passive intermodulation (PIM) source, measuring a polarization of the interference signal, by comparing the two or more signals, to estimate a shape of the PIM source, and generating information regarding the shape to facilitate locating of the PIM source. Other embodiments are disclosed.

Aspects of the subject disclosure may include, for example, causing radio frequency (RF) signals to be transmitted via an antenna system in a plurality of directions, and responsive to transmission of the RF signals, monitoring signals that are received by the antenna system to detect an interference signal that originates from a passive intermodulation (PIM) source. Other embodiments are disclosed.

Aspects of the subject disclosure may include, for example, detecting an interference signal in two or more signals received via orthogonally-polarized elements of an antenna system, the interference signal originating from a passive intermodulation (PIM) source, measuring a polarization of the interference signal, by comparing the two or more signals, to estimate a shape of the PIM source, and generating information regarding the shape to facilitate locating of the PIM source. Other embodiments are disclosed.

Aspects of the subject disclosure may include, for example, causing radio frequency (RF) signals to be transmitted via an antenna system in a plurality of directions, and responsive to transmission of the RF signals, monitoring signals that are received by the antenna system to detect an interference signal that originates from a passive intermodulation (PIM) source. Other embodiments are disclosed.

The invention relates to the technical field of electronic component testing for investigating or analyzing internal microstructures and physical properties of materials by utilizing an electrical means, and discloses an online testing and analyzing method for physical properties of electronic component materials, which comprises the following steps of: constructing a composite excitation signal formed by linearly superposing a main carrier voltage and a perturbation wave voltage; applying the signal to a to-be-tested electronic component and acquiring response current; and extracting an intermodulation current amplitude at an intermodulation frequency point in the frequency spectrum of which the linear response interval is excluded, calculating a nonlinear response coefficient of the material in combination with the excitation amplitude, and comparing the nonlinear response coefficient with a preset degradation threshold so as to judge whether the nonlinear response coefficient is qualified or not. By extracting intermodulation components which cannot be generated by linear contact resistance, physical isolation of external contact noise in a frequency domain is realized, and the problem that contact resistance fluctuation and material intrinsic aging cannot be distinguished in a traditional linear impedance test is solved.

The invention relates to the technical field of power battery health state evaluation and anomaly recognition, in particular to a remote health state analysis and anomaly recognition method for an electric bicycle battery, which comprises the following steps of: under an access working condition, applying small-signal active excitation and synchronously acquiring to form an opportunity diagnosis excitation data window; time-frequency coupling modeling including equivalent impedance modeling, harmonic wave and intermodulation fingerprint modeling, Koopman operator modeling and entropy coefficient difference is carried out, and a spectral measurement geometric distance is constructed through optimal transmission to generate a multi-domain response packet, a physical invariant vector and an uncertainty matrix; according to the geometric distance and consistency score gating and hierarchical standardization, obtaining a health state estimation record and an abnormal event set by adopting a shape-limited health mapping model; and in combination with mapping Jacobian and dual potential, generating an opportunity diagnosis incentive plan of a next period by adopting D-optimal test design, and updating a group health manifold, thereby realizing cross-environment, cross-equipment and traceable remote health assessment and early anomaly recognition.

The invention relates to the technical field of on-line monitoring, in particular to an insulation fault on-line monitoring method and system for a medical IT system control cabinet. The method comprises the following steps: selecting a non-integer frequency multiplication detection frequency according to equivalent ground distributed capacitance in a previous monitoring period, and superposing the non-integer frequency multiplication detection frequency with a fundamental frequency to form a composite signal injection system; collecting signals to calculate a voltage instantaneous harmonic distortion rate change gradient, and selecting a time window to split the leakage current according to the change gradient; on the basis of dispersion estimation signal-to-noise ratio weighted fusion current vectors, insulation resistance and distributed capacitance are calculated; constructing a four-dimensional original feature vector composed of the insulation parameter, the phase difference and the intermodulation component energy; constructing a diagonal weighting matrix based on the resistance-capacitance ratio and the gradient to transform a feature vector, and determining the fault attribution through the Mahalanobis distance calculation with the fault template library. According to the scheme, harmonic interference can be avoided, calculation stability can be improved, insulation instantaneous sudden change can be quickly responded, and different fault types can be accurately distinguished to guide maintenance.

An apparatus and method are provided for digital predistortion of an electrical signal to pre-compensate for nonlinear distortions in a nonlinear channel (e.g., a nonlinear channel including a high-power amplifier). The digital predistortion processor includes a nonlinear filter. Filter coefficients are determined using a modified input electrical signal having multiple simultaneous tones, using an iterative process which adapts the modified input electrical signal to reduce levels of intermodulation distortions in a modified output electrical signal.

The embodiment of the utility model provides a dual-polarization dielectric dipole antenna, the antenna comprises a cross-shaped radiation unit and a guide sheet, the cross-shaped radiation unit comprises a first dielectric plate and a second dielectric plate which are in cross-shaped vertical cross connection; the feed balun circuit on the second dielectric plate crosses the side edge of the top of the first dielectric plate and is connected with the radiation arm on the same side surface of the second dielectric plate; a through hole is formed in the position, at the crossed connection position of the first dielectric plate and the second dielectric plate, of the second dielectric plate and is flatly attached to the first dielectric plate, so that the feed balun circuit on the first dielectric plate is connected to the radiation arm on the same face of the first dielectric plate through the through hole along the penetrating plane. According to the embodiment of the invention, the number of holes in the cross-shaped radiation unit is reduced, so that the antenna is simple to manufacture, and the production cost and the intermodulation distortion risk are reduced. In order to further reduce radiation unit holes, the two groups of feed balun circuits can be wound and crossed from the top, or one group of radiation arms are optimized into slot coupling feed, and coupling perforation is canceled.

A three-dimensional (3D) magnetic particle imaging (MPI) method and system without rotating a field-free line (FFL) are disclosed. In accordance with the method, an FFL is generated such that magnetic particles in a region far from the FFL enter a magnetic saturation state. Further, a non-uniform mixed-frequency excitation magnetic field parallel to the FFL is applied to generate intermodulation response signals. In addition, the intermodulation response signals are acquired, amplified and filtered. Moreover, the intermodulation response signals are transmitted to a digital signal processing unit and an image reconstruction unit, and an encoding matrix is constructed. Additionally, a one-dimensional (1D) concentration distribution of the magnetic particles is reconstructed based on the encoding matrix and an actually measured voltage signal. The FFL is driven for line-by-line scanning along a vertical plane of the FFL, thereby achieving 3D imaging.

The invention relates to the technical field of microelectronics, semiconductors and communication, and discloses a radio frequency switch chip, and the circuit structure of the radio frequency switch chip comprises a transformer type differential inductor T-L1, a transformer type differential inductor T-L2, a capacitor C1, an NMOS transistor M1, an NMOS transistor M2, a gate resistor RG1, and a gate resistor RG2. The radio frequency switch chip provided by the invention adopts a differential structure, so that the parasitic inductance effect of a grounding key and a wire during packaging and testing can be eliminated, and the insertion loss and the isolation performance are improved; compared with a single-end port, the lower impedance of the differential port is more beneficial to improving the power capacity of the switch; the differential structure allows the transformer type differential inductor to use differential signal characteristics, the equivalent quality factor of the inductor is improved, and the circuit performance is improved; the differential structure can improve the linearity of the circuit, especially the second-order intermodulation effect; the differential structure can be compatible with a modern silicon-based CMOS radio frequency system, and an additional balun is not needed for signal conversion.

An electronic device may include wireless circuitry. The wireless circuitry can include a first input transistor, a first capacitance neutralization having a source terminal coupled to a tail node, and a second order intermodulation generation circuit configured to produce second order intermodulation signals at the tail node. The wireless circuitry can further include a second input transistor and a second capacitance neutralization transistor having a source terminal coupled to the tail node. The first and second capacitance neutralization transistors can be cross-coupled with the input transistors. A fixed or adjustable current source can be coupled to the tail node. The second order intermodulation generation circuit can include a transistor biased in a weak inversion mode.

The invention provides a multi-port multi-band intermodulation test method and equipment, and the method comprises the following steps: controlling one or more signal sources to respectively generate carrier signals of two different frequency points in respective target frequency bands; combining the carrier signals into a mixed wave signal through a signal cross network, and distributing the mixed wave signal into multiple paths of test signals, so that each path of test signal comprises the mixed wave signal of one frequency band or multiple frequency bands so as to access a signal port of external passive equipment; and polling and collecting reflected signals generated by each path of test signals through a signal collection unit, and generating test data based on the reflected signals. According to the method, intermodulation testing of multiple frequency bands is achieved, multi-frequency-band intermodulation testing can be conducted on multiple external passive devices at the same time, or multi-frequency-band intermodulation testing can be conducted on multiple ports of the external passive devices, and therefore the intermodulation detection efficiency is improved.

The invention relates to the technical field of mobile communication, in particular to a dual-polarization low-frequency oscillator unit and antenna based on coupled feeding, which comprises a radiation part and a feeding part, the radiation part comprises four radiation arms, the four radiation arms are symmetrically arranged in a cross manner, and two radiation arms on a diagonal form a pair of radiation groups, the four radiation arms jointly form two pairs of radiation groups, the two pairs of radiation groups are used for generating radiation of different polarizations, a PCB coupling plate is arranged at the top of the feed part, four feed metal sheets are integrated on one side face of the PCB coupling plate, and the four feed metal sheets are arranged on the other side face of the PCB coupling plate. The PCB coupling plate and the radiation part are pressed and fixed, and the four feed metal sheets and the four radiation arms are coupled and fed in a one-to-one correspondence manner; compared with a traditional PCB radiating surface and a metal plate radiating surface needing to be electroplated, the material cost is obviously saved, a traditional feeding scheme with welding spots is replaced with coupled feeding, and the problem that the whole machine intermodulation is unstable due to the welding spots of the traditional radiating surface is solved.

The invention discloses a method for automatically setting a working frequency based on a field radio frequency environment, which relates to the technical field of wireless communication, and comprises the following specific steps of: acquiring field radio frequency environment data in real time through a wireless frequency data acquisition module, and storing the field radio frequency environment data in a database; the data processing module screens non-interference frequency points based on third-order intermodulation interference compatibility calculation, the working frequency of the receiver and the working frequency of the transmitter are dynamically adjusted through the equipment control module, and the database, the data processing module and the equipment control module cooperate to achieve automatic frequency switching. A receiver in the method is provided with a standby receiving sub-module, when it is detected that a current frequency point is interfered, the current frequency point is automatically switched to a standby frequency point, stable operation of a system is ensured, the transmitter synchronizes the frequency with the receiver through a communication protocol in a speaking state, signal transmission is stopped in a mute state, environment interference can be monitored in real time, manual intervention is not needed, and the method is suitable for popularization and application. Manual frequent manual operation for frequency adjustment is avoided, and the anti-interference capability of a wireless communication system is remarkably improved.

The invention provides a multi-port multi-frequency-band intermodulation test device, and the device comprises a plurality of signal sources which work in different frequency bands, and each signal source is used for generating two paths of carrier signals of different frequency points in the same frequency band; the signal cross network is used for combining two paths of carrier signals generated by each signal source of the same frequency band into a mixed wave signal and then distributing the mixed wave signal into multiple paths of test signals, and each path of test signal comprises the mixed wave signal of one or more frequency bands so as to be accessed to a signal port of external passive equipment; the signal acquisition unit is used for polling and acquiring reflection signals generated by each path of test signals; and the controller is used for controlling the signal source to generate a carrier signal and generating test data according to the reflected signal. The intermodulation test device can perform multi-band intermodulation test on a plurality of external passive devices at the same time, or perform multi-band intermodulation test on a plurality of ports of the external passive devices, so as to improve the intermodulation detection efficiency.

Systems and methods of passive intermodulation (PIM) detection in a radio frequency (RF) system including: injecting, from each port of a two-port PIM analyzer, two test tones or a wideband modulated carrier signal into the system one port at a time; receiving, at each port, a response signal from the system in response to the test tones or wideband modulated carrier signal; injecting, from two ports of the two-port PIM analyzer, test tones or a wideband modulated carrier signal into the system; receiving, at the two ports, a response signal from the system in response to the test tones or wideband modulated carrier signal; and identifying one or more PIM sources based on the response signals.

The invention discloses a broadband high-precision voltage compensation control method of a power amplifier, relates to the technical field of broadband compensation, and is used for solving the problem of low voltage compensation efficiency caused by cooperative distortion caused by mutual regulation and control when the signal frequencies of different input channels are close. Recording information of the input signal is called to judge the signal type of the input signal, when the multi-frequency signal exists in the analysis database, the signal amplitude and the signal frequency of the multi-frequency signal are collected, the high-order intermodulation distortion degree of the input signal is judged, and the distortion index of the multi-frequency signal is calculated; selecting to start intermodulation distortion processing or enter a frequency coexistence risk test mechanism according to the high-order intermodulation distortion degree of the multi-frequency signals, calculating frequency intermodulation characteristics of different single-frequency signals, and performing effect integration on the frequency intermodulation characteristics of all the single-frequency signals in the analysis database according to the number of the single-frequency signals; and judging whether to carry out intermodulation distortion processing or not by combining the distortion index of the multi-frequency signal.

A dual-mode radar arranged for harmonic and intermodulation operation, said dual-mode radar comprising a transmitter system arranged for detecting an object, said transmitter system comprising a main transmitter arranged for transmitting a first signal towards said object, said first signal having a first frequency, at least one auxiliary transmitter arranged for transmitting a second signal, simultaneously with said first signal, towards said object, said second signal having a second frequency, said second frequency being different, but in a same order of magnitude, to said first frequency, and a receiver system, comprising a receiver arranged for simultaneously receiving a harmonic return signal corresponding to said first signal and receiving an intermodulated return signal corresponding to said first and second signal.

The invention provides an intermodulation test network and a control method thereof. The method comprises the following steps: sending a test instruction to a plurality of intermodulation test devices through a switch; and receiving test data uploaded by the plurality of intermodulation test devices based on the switch, and generating an intermodulation test report based on the plurality of test data. According to the method, a test instruction is sent to a plurality of intermodulation test devices through a switch, so that the plurality of intermodulation test devices can work simultaneously, and a signal source is respectively controlled to generate carrier signals in a target frequency band. Compared with a traditional mode that a single device is tested one by one, the multi-device collaborative testing mode greatly shortens the testing time and improves the testing efficiency.

The invention relates to the technical field of radio frequency switches, in particular to a low-intermodulation and high-reliability coaxial radio frequency switch which comprises a connector assembly, a cavity cover assembly and a coil assembly, the connector assembly comprises a center connector and a branch connector, the cavity cover assembly comprises a cavity cover and a reed, a supporting medium is installed on the reed, a lower spring is arranged outside the supporting medium in a sleeving mode, and the coil assembly is arranged in the cavity cover. The coil assembly comprises a plurality of coils, iron cores provided with upper springs are arranged on the coils and connected with the corresponding supporting media, and during power failure, the compression elastic force of the upper springs is larger than that of the lower springs, so that the iron cores in the coils move downwards to drive the corresponding supporting media and the corresponding reeds to move downwards. When the coaxial radio frequency switch is switched on, the reed is respectively contacted and conducted with the central connector and one branch connector, so that when the coaxial radio frequency switch is not powered on or the switch fails, one path of the switch is still switched on, at the moment, a system connected with the switch can still work in a default state, and a failure mode can be guided to a safety mode.

The present invention relates to an audio-video signal processing apparatus, which comprises: an audio-video application circuit, a power supply circuit, and at least one impedance matching circuit, wherein the audio-video application circuit is configured to receive, process, and output audio and / or video intermodulation signals; the power supply circuit is configured to output a DC voltage to the audio-video application circuit for powering it; the impedance matching circuit includes a plurality of impedance elements, at least one input end, and at least one output end, and is arranged before or inside the audio-video application circuit. The audio-video signal processing apparatus of the present invention can perform impedance matching and timing adjustment on the power supply signal and the audio and / or video intermodulation signals, thereby reducing the intermodulation distortion generated by the audio and / or video intermodulation signals during transmission through the impedance matching circuit.

Provided is a technique for suppressing intermodulation distortion. Provided is a plasma processing apparatus comprising: a chamber; a substrate support that is disposed in the chamber and includes a lower electrode; an upper electrode that is disposed above the substrate support; a source RF generator that is configured to supply a source RF signal to the upper electrode or the lower electrode to generate plasma in the chamber; an impedance matching device that is electrically connected to a transmission line between the source RF generator and the upper electrode or the lower electrode, the impedance matching device including a first low-speed matching circuit and a first high-speed matching circuit that are connected in parallel to each other; a bias generator that is configured to supply a bias signal to the lower electrode; and a control unit that is configured to perform a low-speed matching operation on the source RF signal by the first low-speed matching circuit during the first period, and to perform a high-speed matching operation on the source RF signal by the first high-speed matching circuit during a second period after the first period.

The invention discloses a time interference double-target electrical stimulation system, which comprises a signal generation unit used for generating multiple paths of carrier signals and adjusting the frequency, amplitude and / or phase of the carrier signals; the current output unit is used for converting the multiple paths of carrier signals into multiple paths of carrier currents, and electrical isolation and intermodulation suppression are provided between the multiple paths of carrier currents; the electrode unit is electrically connected with the current output unit and comprises a plurality of electrodes and a position subunit, the plurality of electrodes are used for receiving the multi-channel carrier current so as to discharge in an attached target area, and the position subunit is used for determining the attaching position of each electrode; and the control unit is used for controlling the discharge of the plurality of electrodes, detecting the impedance and carrier current at the plurality of electrodes to assist the position subunit in determining the fitting position and detecting the frequency and / or phase of the plurality of carrier current to control the signal generation unit to adjust the frequency and / or phase of each path of carrier signal. The system realizes independent stimulation of two target spots in a hardware-level time interference mode, has signal output with high stability and low mutual interference, and can perform real-time feedback regulation and safety protection.

The present invention relates to a simple VHF frequency band channel transceiver, belonging to the technical field of very high frequency transceivers. It is composed of a device box and a circuit board. The device box is composed of a shell, a cover plate and a shielding cavity. The receiving / transmitting channel module installed on the circuit board contains a receiving circuit, a transmitting circuit and a power supply circuit; the receiving circuit is composed of a low-noise amplifier frequency selection, mixing, intermediate frequency amplification, intermediate frequency crystal filtering, automatic gain control, receiving demodulation and receiving frequency synthesis circuit; the transmitting circuit is composed of a transmitting frequency synthesis, a transmitting pre-stage drive amplifier, a transmitting post-stage drive amplifier and a power detection circuit; a plurality of shielding cavities are milled in the shell and the cover plate, and the shielding cavities are respectively equipped with individual module circuits of the receiving circuit and the transmitting circuit, and the shell and the cover plate are sealed and shielded for the circuit board. The integrated design of the transceiver channel machine and the radio frequency carrier 4FSK digital signal modulation are realized. The receiving intermediate frequency, image frequency, intermodulation and spurious response indicators are excellent, the multi-channel operation has no crosstalk, the analog sensitivity is high, the volume is small, the noise is small, the harmonic spurious suppression is high, and the receiving dynamic range is large.

A wireless communication system includes a transmitter, a plurality of passive substantially linear medium portions including one or more first portions and a second portion, one or more passive substantially nonlinear medium portions disposed proximate the substantially linear medium portions, and for each first portion, a dielectrically lossy or magnetically lossy first material disposed on the first portion. When the transmitter transmits first and second radio waves, the substantially linear and nonlinear medium portions receive the first and second radio waves and generate first and second signals propagating therein, where at least one intermodulation signal is generated in the one or more substantially nonlinear medium portions from the first and second signals, and the one or more first materials reduces the generation of the at least one intermodulation signal by at least 2 dB.

The invention discloses an oscillator structure and a base station antenna. The oscillator structure comprises a reflecting plate and two groups of oscillator bodies, each oscillator body comprises a feeder circuit board, a radiation sheet and a buckling part, the two groups of feeder circuit boards are mounted on the same side of the reflecting plate and are arranged in a crossed manner, the radiation sheet is a metal sheet, and the buckling part is arranged on the radiation sheet and can buckle the radiation sheet on the feeder circuit board in the same group. According to the scheme, the dipole antenna adopts a circuit board feeder mode, electric signals are coupled to the radiation sheet, and the advantage that the frequency band of the dipole antenna is wide is effectively utilized. Meanwhile, the radiation sheet can be formed by stamping a relatively thin metal sheet, so that the weight of the oscillator is greatly reduced, a good intermodulation index is achieved, mold opening is not needed, the cost is reduced, and the main advantages of a metal plate stamping process, a PCB feeder line and a dipole antenna are integrated.

Provided are a scalable analog passive intermodulation (PIM) module, a method of controlling analog PIM, a signal processing circuit, and a sensor device. The scalable analog PIM module includes a first plural number of digital-to-analog converters (DACs), a first plural number of static random access memory (SRAM) calculators connected to the first plural number of DACs, at least one analog-to-digital converter (ADC) connected to the first plural number of SRAM calculators and configured to convert an analog convolution result signal into digital convolution data, and an analog PIM controller configured to output an enable control signal for enabling a second number, which is equal to or less than first plural number, of SRAM calculators among the first plural number of SRAM calculators to the first plural number of SRAM calculators on the basis of the convolution data output from the ADC.

The invention discloses a method for acquiring passive intermodulation interference caused by oxidation corrosion of a base station antenna, and aims to further supplement and improve the existing research so as to quantitatively evaluate the passive intermodulation interference generated after the oxidation corrosion of the base station antenna. An analysis object is set as the side surface of a microstrip line conductor, firstly, the amplitude coefficient AD2 of voltage of each point in the lower edge area of the side surface of an unoxidized and corroded microstrip line under the action of a single carrier signal is determined, and then after it is determined that the microstrip line is oxidized and corroded, the amplitude coefficient AD2 of voltage of each point is determined. According to the method, the tunneling current density JMIM and the total tunneling current IMIM of the oxidation corrosion areas are obtained according to the average voltage value of the oxidation corrosion areas, and on the basis, the third-order passive intermodulation voltage V3rd-PIM (t) is calculated, so that the passive intermodulation interference generated after oxidation corrosion of the base station antenna is quantitatively evaluated.

A method and apparatus for use in improving linearity sensitivity of MOSFET devices having an accumulated charge sink (ACS) are disclosed. The method and apparatus are adapted to address degradation in second- and third-order intermodulation harmonic distortion at a desired range of operating voltage in devices employing an accumulated charge sink.