6results about How to "Avoid nonlinear distortion" patented technology

The utility model discloses a broadband anti-interference down-conversion device and a radio frequency receiving system, and relates to the wireless communication technology. The device comprises a first frequency converter, a second frequency converter, a power divider and a local oscillator unit. Wherein the first frequency converter and the second frequency converter realize two-stage frequency conversion of radio frequency signals, the second frequency converter adopts a dual-channel ping-pong switching structure, and two channels are connected with the output end of the first frequency converter through the power divider; the local oscillation unit provides independent local oscillation signal input for the first frequency converter, the second frequency converter and the local oscillation unit. According to the utility model, the broadband and high-dynamic interference suppression performance is realized through the combination of two-stage frequency conversion and a dual-channel ping-pong switching structure.

This invention discloses a super-linear loudspeaker and its manufacturing method, comprising a square bar-shaped loudspeaker body that cooperates with a display screen. The loudspeaker body includes a support frame, which includes a first-stage frame that cooperates with a sound-generating unit and a second-stage frame that cooperates with a magnetic circuit unit. The first-stage frame and the second-stage frame are arranged in a stepped manner. The magnetic circuit unit includes a magnetic cup and a magnet disposed within the magnetic cup. The sound-generating unit includes a diaphragm disposed at the top of the first-stage frame and a voice coil that drives the diaphragm to vibrate. A magnetic gap is formed between the magnet and the sidewall of the magnetic cup to cooperate with the voice coil. A main frame is disposed between the voice coil and the diaphragm. The top of the main frame is fixedly connected to the diaphragm, and the bottom of the main frame is fixedly connected to the voice coil. By optimizing the loudspeaker shape, adding a small diaphragm structure welded to the back of the FPC, and optimizing the magnetic circuit structure, the low frequency is better during sound generation, and the power consumption, distortion, and space occupation are smaller, resulting in higher loudness.

The utility model discloses a high-voltage live display locking device for monitoring leakage current, which belongs to the technical field of lightning arrester monitoring and comprises an electric leakage detection module, a signal processing module, a master control module, an alarm module, a locking module and a power supply module. The electric leakage detection module is used for collecting a leakage current signal and transmitting the leakage current signal to the signal processing module; the signal processing module converts the leakage current signal into a voltage signal and transmits the voltage signal to the main control module; the main control module responds to the voltage signal to generate an alarm signal and a blocking signal; the alarm module responds to the alarm signal to execute an alarm action; the locking module responds to the locking signal to execute a locking action; the power supply module provides working voltage for the electric leakage detection module, the signal processing module, the main control module, the alarm module and the locking module. According to the utility model, the problem of low safety caused by the fact that the electrification condition of the lightning arrester corresponding to other electrical equipment is not considered in the prior art is solved.

The application relates to a weight stacking method of a digital power amplifier, a digital power amplifier system and a radar device, wherein a digital power amplifier array in the digital power amplifier comprises a plurality of parallel digital power amplifier units; each digital power amplifier unit comprises a plurality of main power amplification units and at least two power allocation units which are in parallel and independently controlled; the rated output power of the main power amplification unit is greater than that of the power allocation unit; a weight combination scheme of the digital power amplifier unit is calculated according to a received target output power, and corresponding control coding is generated; the on and off states of the main power amplification units and the power allocation units are controlled based on the control coding, so that the input radio frequency input signal of the digital power amplifier is shunt weighted and amplified, the problem of insufficient power control performance is solved, power regulation is changed from load modulation in an analog domain to power unit combination in a digital domain, and nonlinear distortion introduced by analog regulation is avoided.

This invention relates to the field of sensor technology, and discloses a capacitive touch detection circuit and method. The capacitive touch detection circuit includes a charge compensation module, a voltage-to-current conversion module, an integrating capacitor, a quantization circuit module, and a counter. The charge compensation module is used to compensate for the charging and discharging of an external touch capacitor, adjusting the charge on the touch capacitor to a predetermined charge range corresponding to a reference voltage. The voltage-to-current conversion module is used to convert the remaining charge on the touch capacitor after compensation by the charge compensation module into current and output it. The integrating capacitor is used to integrate the current to obtain an integrated voltage. The quantization circuit module is used to quantize the integrated voltage and control the integrated voltage to be stable within a preset voltage range of the reference voltage. The counter is used to count the output of the quantization circuit module to obtain a digital code representing the touch capacitance value. This invention can achieve touch detection performance with high linearity, low power consumption, small area, and high noise immunity.

The application provides a high-precision time measurement system and method, wherein the time measurement method comprises a signal conditioning circuit, a PLL frequency division, a coarse measurement module, a fine measurement module, a temperature compensation module, data processing and a network interface for external communication. The high-precision time measurement system comprises a reference clock source, a signal conditioning circuit, a core FPGA and a communication interface. The application adopts an adaptive interpolation type TDC and a temperature compensation technology to realize high-precision time measurement. The time frequency measurement technology can be applied to laser radar, intelligent driving and the like, has high precision and low non-linear error, the system maintains extremely high long-term stability in a wide temperature range, greatly reduces a measurement dead zone, is suitable for high-speed continuous event measurement, and reduces cost. And the high programmability of the FPGA makes the system easy to integrate with other digital systems and expand functions.