Abstract:
Apparatuses, systems, and methods for high-pass filtering pre-emphasis circuits. A device may use a pre-emphasis driver to provide a multi-level signal based on multiple binary signals. The pre-emphasis driver includes a primary driver coupled in parallel with at least one equalizer path, each of which includes an equalizer driver and a filtering element. The filtering element may be an AC filtering element, such as a capacitor. The equalizer paths may contribute equalized signal(s) which have a high-pass filtering behavior. The pre-emphasis circuit may combine the primary signal from the primary driver and the equalized signals to generate an overall output multi-level signal. In some embodiments, the pre-emphasis driver may be a pulse amplitude modulated (PAM) driver, such as a PAM4 driver with four levels of the multi-level driver.
Abstract:
A driver circuit of a PAM-N transmitting device transmits a PAM-N signal via a communication channel, wherein N is greater than 2, and the PAM-N signal has N signal levels corresponding to N symbols. A PAM-N receiving device receives the PAM-N signal. The PAM-N receiving device generates distortion information indicative of a level of distortion corresponding to inequalities in voltage differences between the N signal levels. The PAM-N receiving device transmits to the PAM-N transmitting device the distortion information indicative of the level of the distortion. The PAM-N transmitting device receives the distortion information. The PAM-N transmitting device adjusts one or more drive strength parameters of the driver circuit of the PAM-N transmitting device based on the distortion information.
Abstract:
A dither amplitude circuit has a current circuit for receiving DC voltage signals and generating a direct current on a basis thereof, and generating a dither signal, and a dither current on the basis thereof, applying the dither current to the direct current in order to obtain a drive current, artificially modulating the amplitude of the dither signal or a directly modulated drive current with an amplitude modulation deviation on a periodic basis such that a quantization threshold is reliably exceeded. The dither amplitude circuit also has a return current detection circuit that generates numerous quantized digital values in a time period on a basis of the drive current flowing through a load, such that the dither amplitude can be determined from the numerous digital values.
Abstract:
Embodiments of the invention include a wakeup receiver (WRX) featuring a charge-domain analog front end (AFE) with parallel radio frequency (RF) rectifier, charge-transfer summation amplifier (CTSA), and successive approximation analog-to-digital converter (SAR ADC) stages. The WRX operates at very low power and exhibits above-average sensitivity, random pulsed interferer rejections, and yield over process.
Abstract:
The present invention is to generate a spatially phase modulated electron wave. A laser radiating apparatus, a spatial light phase modulator, and a photocathode are provided. The photocathode has a semiconductor film having an NEA film formed on a surface thereof, and a thickness of the semiconductor film is smaller than a value obtained by multiplying a coherent relaxation time of electrons in the semiconductor film by a moving speed of the electrons in the semiconductor film. According to the configuration, a spatial distribution of phase and a spatial distribution of intensity of spatial phase modulated light are transferred to an electron wave, and the electron wave emitted from an NEA film is modulated into the spatial distribution of phase and the spatial distribution of intensity of the light. Since the spatial distribution of phase of the light can be modulated as intended by a spatial phase modulation technique for light, it is possible to generate an electron wave having a spatial distribution of phase modulated as intended.
Abstract:
Methods and systems for digitization of broadband analog signals may comprise in a radio frequency (RF) transceiver comprising a diplexer, first and second automatic gain and slope control (ASCS) modules, a combiner, and an analog to digital converter (ADC): receiving an input RF signal comprising at least two signals, splitting the input RF signal in the frequency domain into first and second signals of different frequency utilizing the diplexer, configuring a frequency-dependent gain level for each of the first and second signals utilizing the first and second ASCS modules, combining output signals from the first and second ASCS modules utilizing the combiner, and converting the combined output signals to a digital signal utilizing the ADC. The frequency dependent gain levels of the first and second signals may be configured to enable the ADC to operate with an effective number of bits (ENOB) of approximately 10.
Abstract:
A data transmission method and a device are disclosed and relate to the field of communications technologies, so that a channel resource preemption probability of a device can be effectively increased by reducing a CCA interval at which a CCA is performed on a channel resource. The method includes: determining, by a first device, a CCA start moment at which a clear channel assessment CCA is performed; determining, by the first device, a CCA interval, where the CCA interval is a time interval between two adjacent CCAs, and a time interval between any two adjacent CCAs is less than a preconfigured data frame period; performing, by the first device, a CCA process according to the CCA start moment and the CCA interval; and sending, by the first device, data at an end moment of the CCA process. The method and the device are used for data transmission.
Abstract:
A transmitter, a transmission system and a transmission method whereby AM-PM distortions can be compensated with high accuracy without affecting the functions of a predistortor, a ΔΣ modulator and so on. The transmitter includes: a baseband signal generation circuit that outputs the amplitude value and phase value of a baseband signal; a ΔΣ modulation circuit that performs a ΔΣ modulation of the outputted amplitude and phase values to output a pulse signal train; a power supply modulation circuit that supplies, to a pre-stage amplifier, a voltage determined in accordance with the outputted amplitude value; the pre-stage amplifier and a post-stage amplifier that amplify the outputted pulse signal train; and a filter circuit that generates an output signal from the pulse signal train as amplified and outputs the output signal. The power supply modulation circuit determines the voltage for canceling a phase error occurring in the post-stage amplifier.
Abstract:
A method for improving acoustics of amplitude modulation (AM) audio signal, comprising: amplifying and mixing, with an amplitude modulation (AM) front-end module, an analog AM signal and an automatic gain control (AGC) signal from an AGC module; converting and sampling, with an analog-digital converter and down-sampling module, the amplified and mixed signal to generate a digital AM signal; digitally mixing, with a digital mixer module, the digital AM signal to generate a first digital AM envelope signal; compensating, with an AM compensator module, the first digital AM envelope signal by an AM compensating AGC signal from the AM compensator module to generate a second digital AM envelope signal; demodulating, with a demodulation module, the second digital AM envelope signal; and outputting, with an output module, a demodulated AM audio signal.
Abstract:
A system can be used for contactless communication of information between a first device and a second device, each having an antenna intended to be coupled via a near magnetic field. The first device includes a transmit chain having first circuitry configured to generate a digital data stream corresponding to the information to be transmitted, and second circuitry configured to generate a first amplitude-modulated and dithered signal in the antenna of the first device from this stream and from an application of a first dithering. The second device includes a receive chain having third circuitry configured to carry out a frequency transposition of a second amplitude-modulated and dithered signal originating from the first signal, with application of a second dithering synchronous with the first dithering.