6 results about "Carrier leakage" patented technology

The invention discloses a transmitting and receiving device and a carrier leakage calibration method. The device comprises a control module, a transmitting compensation module, a transmitter, a calibration switch module, a receiver and a receiving compensation module, when the loopback mode is started, the transmitting compensation module generates an analog direct-current signal, the transmitter converts the analog direct-current signal into an uncalibrated radio-frequency signal, and the uncalibrated radio-frequency signal enters the receiver through the calibration switch module; the receiver converts an uncalibrated radio frequency signal into an analog intermediate frequency signal, the receiving compensation module generates signal power according to the analog intermediate frequency signal, and the control module adjusts a direct current offset parameter sent to the receiver and a receiving compensation parameter sent to the receiving compensation module according to the signal power, and performs direct current offset calibration on the receiver; and the control module adjusts the transmission compensation parameter sent to the transmission compensation module according to the signal power, and carries out carrier leakage calibration on the transmitter. According to the invention, the calibration effect and the calibration stability under process deviation can be improved.

This application provides a method and apparatus for detecting and evaluating carrier leakage signals in mobile terminals, belonging to the field of leakage detection technology. The method includes: performing carrier detection on mobile medical devices and surrounding mobile terminals in a hospital's mobile medical area to obtain carrier data; performing quantum spectrum analysis on the carrier data to determine the carrier leakage frequency band; calculating the leakage power density of the carrier leakage frequency band and the spectral overlap between the carrier leakage frequency band and the operating frequency band of the mobile medical device; determining an electromagnetic interference risk value based on the leakage power density and spectral overlap; generating a risk report when the electromagnetic interference risk value exceeds a preset first threshold; verifying the risk report using a deviation comparison method to obtain verification results, including inaccurate and accurate reports; and generating a risk warning based on the risk report corresponding to the accurate verification result. This application provides efficient technical support for leakage detection of medical devices in complex electromagnetic environments within hospitals.

The application discloses a fast recovery power device with embedded tunnel diode structure and a production method thereof, wherein the power device has a plurality of uniformly arrayed heavy doped regions with opposite doped types under a neutral body region, and the heavy doped regions form a tunnel PN junction structure with the doped regions with opposite doped types in the neutral body region; the tunnel PN junction structure can provide an additional minority carrier leakage conduction channel when the power MOSFET device is switched from a conducting state to a closed state, reduces the tail current when the device is closed, makes the power device quickly closed from an open state, and thus improves the working speed of the device and expands the frequency band range of the power device. The application realizes the fast recovery characteristic of the device through the process steps of adding the arrayed opposite heavy doped regions and rapid thermal annealing, makes the power device have the advantages of low cost and fast recovery, and breaks the barrier that the VDMOS power device can only be used in the medium and low frequency field applications.

The application discloses a zero intermediate frequency satellite communication signal processing method and system based on an embedded microcontroller, and the method comprises the following steps: encoding and framing original data, generating I / Q digital baseband waveforms through QPSK mapping, upsampling and shaping filtering, and converting analog signals through a double-channel DAC. In view of Sinc fading and adjacent channel leakage caused by the zero-order holding effect of the DAC, two-stage cascade suppression is adopted: the first stage of attenuation is performed in the digital domain; the second stage of physical filtering is performed in the analog domain between the DAC and the mixer by using the stop band notch characteristic of the symmetrical active differential low-pass filter circuit, and the independent direct current bias adjustment is used for IQ balance adjustment to eliminate the carrier leakage. Finally, the mixer is used for one-step up-conversion, and a power amplifier is used for emission. The method does not need closed-loop digital IQ correction, significantly reduces resource consumption, and improves the adjacent channel power ratio and radio frequency quality.

The application provides a semiconductor laser emitter, characterized in that it comprises a cathode and an anode, and a first region and a second region; the first region comprises a capacitor, an inductor and a resistor; the second region comprises a capacitor, a power consumption module and an output power module; through the design, the DBR power consumption, the DBR resistance and the power consumption caused by carrier leakage of the semiconductor laser emitter can be determined.

Quantum cascade lasers (QCLs) are provided, which in embodiments comprise a plurality of stages, each stage comprising alternating quantum well layers and barrier layers, wherein each stage is configured, upon application of an electric field F across the plurality of stages, to inject carriers from a low energy state of an adjacent, upstream stage of the plurality of stages into a high energy state of a lasing stage of the plurality of stages, via tunneling injection through multiple barrier layers comprising barrier layers of the adjacent, upstream stage and barrier layers of the lasing stage, wherein carriers in the lasing stage undergo intraband transitions from an upper laser level of the lasing stage to at least one lower laser level of the lasing stage with the emission of laser light and without carrier leakage.