14results about "Electrial characteristics varying frequency control" patented technology

The invention discloses a tunable band-pass filter and a tuning method and a manufacturing method thereof, and belongs to the technical field of radio frequency communication. The tunable band-pass filter mainly comprises a high-pass filtering unit, a low-pass filtering unit and a control signal input port, and the control signal input port is used for applying an excitation voltage signal with adjustable amplitude and phase to the low-pass filtering unit or the high-pass filtering unit. The bandwidth of the tunable band-pass filter can be continuously tuned by adjusting the amplitude and / or the phase of the excitation voltage signal, and the problem that in the prior art, bandwidth tuning of a band-pass filter at the radio frequency front end is discrete is solved; in addition, the invention further provides a silicon-based manufacturing process of the tunable band-pass filter, bare chips in the radio frequency front end can be integrated on the tunable band-pass filter in a silicon wafer embedding mode, and the defects that a traditional radio frequency front end is large in size and heavy in weight can be effectively overcome.

This invention discloses a gain-variable numerically controlled oscillator, comprising a current-controlled oscillator, a coarse-tuning control circuit, a mid-tuning control circuit, a fine-tuning control circuit, and a gain-adjustable circuit. The coarse-tuning, mid-tuning, and fine-tuning control circuits control the current flowing into the current-controlled oscillator to control its oscillation frequency. The gain-adjustable circuit controls the current in the fine-tuning control circuit to control the frequency gain of the numerically controlled oscillator. By controlling the current in the fine-tuning control circuit through the gain-adjustable circuit to control the frequency gain of the numerically controlled oscillator, the flexibility of the system is improved.

The invention relates to the technical field of frequency correction, in particular to a surface acoustic wave filter frequency response correction system which comprises a node physical characteristic analysis module, a genetic algorithm strategy generation module, a dynamic tuning process evaluation module and a multi-dimensional fitness iterative optimization module. According to the method, internal correlation between a control voltage node and a frequency response drift amount is simulated, analyzed and controlled, unit voltage sensitivity is calculated to construct a Lingehe degree matrix, a comprehensive weight coefficient is calculated based on the matrix, gene position distribution is set, a complete optimization strategy set is formed, and in the iterative optimization process, correction precision is pursued, and the accuracy of the frequency response drift amount is improved. The network input impedance in the tuning process is dynamically simulated and evaluated, impedance path punishment is applied by calculating the length of a forbidden area track, the stability of the tuning process is considered, and under the driving of multi-dimensional fitness evaluation and directional variation, the network input impedance in the tuning process is dynamically simulated and evaluated. And converging and outputting a group of control voltage sequences capable of ensuring the stable path and the optimal correction effect.

Systems and methods for performing automatic frequency control are provided. Instead of relying on individual frequency tuners for each channel of a multi-channel receiver system, the present subject matter uses a single frequency tuner for receiving each channel of the multi-channel receiver system. A locked demodulator may be designated as a reference demodulator and frequency offset values associated with the reference demodulator may be applied to other demodulators of the multi-channel receiver. These frequency offset values may be used by individual demodulators of each channel for correcting corresponding frequency offsets.

According to one or more of the embodiments herein, systems and techniques are provided for demodulating a received signal which has rapidly varying frequency offset such as due to being transmitted or received with a system whose oscillator is rapidly varying or due to Doppler shift variation caused by change of relative motion between the transmitter and receiver, or due to frequency variations caused by a relaying device such as a communications satellite. The techniques herein establish a model for the carrier frequency and use it to compensate for the variations in frequency due to any source.

The application discloses a frequency domain electromagnetic wide-frequency tuning excitation method based on a fractional order capacitor, relates to the field of geophysical electromagnetic methods, and is realized through a wide-frequency tuning circuit, wherein the circuit comprises a direct-current power supply, an H-bridge inverter circuit, a transmitting coil and a fractional order capacitor. The fractional order capacitor is composed of two constituent capacitors, one inductor and two complementary conduction MOSFET switches, the equivalent capacitance is accurately controlled through adjustment of the duty cycle of the switches, and the wide-frequency resonance loop is formed in cooperation with the transmitting coil. After the resonance frequency band is set, the parameters of each component can be calculated and selected, the equivalent capacitance continuously changes in a wide range through duty cycle adjustment, the wide-frequency tuning can be realized without replacement of devices, the amplitude of the excitation current is significantly improved, the signal-to-noise ratio of detection is enhanced, the problems of fixed tuning frequency and low adjustment precision of traditional LC tuning are solved, and the method is suitable for scenes such as metal pipeline detection and geological disaster hidden danger identification.

This application provides an adaptive adjustment method for impedance matching network of a portable radio range extender, comprising: extracting the battery terminal voltage signal and transmit duty cycle from the radio's RF front end; analyzing the battery terminal voltage signal to identify the battery terminal voltage drop pattern and determining the tilt attitude of the drain dynamic load line under the depth of discharge; using an adaptive convergence algorithm to link the rising and falling direction of the tuning capacitor position with the reflection recovery pattern, and when the rising and falling direction is positive, increasing the tuning capacitor position; otherwise, decreasing the position to form a matching network setting; updating the rearranged links of the frequency positions in the memory tuning table according to the matching network setting to generate an adaptive adjustment link; and combining the adaptive adjustment link with the current battery terminal voltage drop pattern and the tilt attitude of the drain dynamic load line to optimize the reflection recovery pattern and determine the impedance mismatch tuning scheme.

The present application relates to the field of frequency correction technology, in particular to a kind of surface acoustic wave filter frequency response correction system, system includes: node physical property analysis module, genetic algorithm strategy generation module, dynamic tuning process evaluation module, multidimensional fitness iteration optimization module.In the present application, the internal correlation between simulation analysis control voltage node and frequency response drift is calculated to construct sensitivity matrix, and based on this matrix, comprehensive weight coefficient and set gene bit allocation are calculated to form a complete optimization strategy set.In the iteration optimization process, not only the correction accuracy is pursued, but also the network input impedance in the tuning process is dynamically simulated and evaluated.The length of forbidden area trajectory is calculated to impose impedance path penalty, and the stability of tuning process is considered.Under the driving of multidimensional fitness evaluation and directional variation, a group of control voltage sequences that can guarantee path stability and have the best correction effect are output.

The invention discloses a frequency domain electromagnetic broadband tuning excitation method based on a fractional order capacitor, which relates to the field of geophysical electromagnetic methods and is realized through a broadband tuning circuit, and the circuit comprises a direct current power supply, an H-bridge inverter circuit, a transmitting coil and the fractional order capacitor. The fractional order capacitor is composed of two constituent capacitors, an inductor and two complementary and conducted MOSFET switches, the equivalent capacitance value is accurately controlled by adjusting the duty ratio of the switches, and the fractional order capacitor is matched with the transmitting coil to form a broadband resonance circuit. After the resonant frequency band is set, the parameters of each component can be calculated and selected, the equivalent capacitance value continuously changes in a wide range through duty ratio adjustment, broadband tuning can be realized without replacing devices, the excitation current amplitude is remarkably improved, the detection signal-to-noise ratio is enhanced, and the problems of fixed frequency point and low adjustment precision of traditional LC tuning are solved. The method is suitable for metal pipeline detection, geological disaster hidden danger identification and other scenes.

The invention relates to the technical field of machine learning, in particular to an intelligent tuning method and system for a surface acoustic wave filter, and the method comprises the following steps: obtaining the parameter data of the filter, generating a hidden space vector and a basic parameter manifold, monitoring the temperature and excitation duration, generating a state vector, and calculating a reconstruction tensor; and adding and updating weight parameters to form a temporary weight, mapping a target index, calculating a geodesic distance, screening an optimal point, and decoding to obtain an optimal tuning parameter combination. According to the method, the characteristic data of the surface acoustic wave filter is mapped into the potential parameter space, the weight is dynamically updated, adaptive tuning of performance offset in operation is achieved, monitoring and normalization processing are conducted in combination with the temperature, the power excitation duration and other states, the tuning parameter offset trend is corrected in time, and the tuning precision is improved. Depending on external element compensation or frequency loop adjustment is avoided, parameter selection accuracy is improved through geodesic distance calculation in performance index mapping and optimal point screening, and it is guaranteed that the filter keeps stable frequency characteristics under complex conditions.

A phase-locked loop design is provide that can operate at a plurality of dissimilar supply voltages. By adjusting the frequency range of a PLL based on the power supply voltage, the same PLL design can operate at different supply voltages.

There are provided methods and systems comprising one or more processing circuitries configured to obtain data informative of a time bias associated with a receiver, wherein said time bias is caused at least by a frequency drift of an atomic clock, and use the data to determine data informative of the frequency drift of the atomic clock. There are also provided methods and systems comprising one or more processing circuitries configured to obtain data informative of a frequency drift associated with a receiver, wherein at least part of the receiver is connected to a frequency source comprising an atomic clock, and use the data to estimate a frequency drift of the atomic clock.