5results about How to "High frequency accuracy" patented technology

The invention discloses a model library-based spaceflight radio frequency signal quality multi-domain evaluation and compensation method, and belongs to the technical field of wireless communication. The implementation method comprises the steps of determining signal system parameters based on various CCSDS standards and a spaceflight protocol system, extracting related parameters of spaceflight standards in a time-frequency domain, generating standard time-frequency domain radio frequency signals, converting the standard time-frequency domain radio frequency signals into a related domain, a modulation domain, an energy domain and a polarization domain, and establishing spaceflight radio frequency signal sub-model libraries of the domains; obtaining a time-frequency domain measured signal through a receiver, integrating time domain information and frequency domain information, and constructing a time-frequency domain sub-evaluation model; constructing a multi-domain comprehensive evaluation model by adopting a parallel data transmission mode and a weight data processing method; calculating the weight of the evaluation result of each domain through an entropy weight method, and obtaining a comprehensive quality evaluation result of the spacecraft radio frequency signal; and based on the distortion coefficient, a robust signal equalization algorithm is adopted to process the signal, the influence of the distortion effect on the signal quality is compensated, and the robustness and the anti-interference capability of signal transmission are improved.

The utility model discloses a spectrum analyzer, comprising a tunable laser used for outputting frequency laser; the frequency expansion module is used for receiving the frequency laser output by the tunable laser, performing frequency expansion processing and then outputting frequency expansion laser; the signal acquisition module is used for acquiring a signal after the frequency expansion laser output by the frequency expansion module passes through the object to be measured; and the data processing module is used for analyzing the signal acquired by the signal acquisition module to obtain the frequency response of the to-be-detected object. According to the spectrum analyzer disclosed by the utility model, the frequency laser output by the tunable laser is subjected to frequency conversion through the frequency expansion module, so that the bandwidth of the spectrum analyzer is greatly expanded, and full-wave band spectrum analysis from purple light to infrared light is realized.

This application discloses a precision capacitance sensing system, comprising a modulation signal source, a sensitive probe, a differential transformer bridge, a signal amplification link, an analog multiplier, and a low-pass filter circuit, all connected in sequence. It also includes a demodulation reference signal source, the output of which is connected to the second input of the analog multiplier. The demodulation reference signal source is used to generate a multi-frequency combination demodulation reference signal, which is composed of a fundamental frequency component and at least two harmonic components superimposed. This invention also discloses a precision capacitance sensing method. By employing a specially designed demodulation reference signal, this application ensures that the system output remains constant within a continuously varying range of the demodulation phase difference, thereby achieving complete insensitivity to phase difference fluctuations and effectively overcoming the performance bottleneck that has long constrained high-precision capacitance sensing.

The application provides a method for automatically calibrating the frequency of an internal crystal oscillator, a controller chip, a household appliance and a storage medium, and the method comprises the following steps: obtaining a commercial alternating voltage signal; sampling the commercial alternating voltage signal at a current frequency of the internal crystal oscillator to obtain a sampling number within a preset sampling period; and obtaining a correction value of the current frequency according to a preset standard number corresponding to the sampling number and the current frequency, and adjusting the current frequency. The application can reduce the dependence on chip port resources while reducing the temperature influence when using the built-in oscillator of the chip.

The present invention discloses a wireless charging circuit, including: a primary circuit and a secondary circuit. The present invention also discloses a wireless charging method and a computer-readable storage medium. The present invention controls the primary full-bridge circuit through a control module, which can improve the frequency accuracy of the primary full-bridge circuit and reduce the frequency operation error range of the primary full-bridge circuit. When charging an electric vehicle, the primary circuit is operated at a preset frequency because the frequency operation error range is small, and the frequency of the primary circuit is captured by a capture module. The operating state of the secondary circuit is controlled according to the acquired primary frequency, so that the frequency of the primary circuit is the same or similar to the frequency of the secondary circuit, thereby improving the charging efficiency and system stability of the wireless charging circuit.