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.

An embodiment of a communication circuit for communicating data across an isolation barrier may include an input circuit to receive a plurality of input data channels, a framing circuit to frame an input data packet from the plurality of input data channels, an encoding circuit to select a characteristic of a data symbol to represent a plurality of bits of the framed input data packet, and a driver circuit to drive one or more data symbols representing the framed input data packet onto an isolator configured to communicate data across the isolation barrier. The encoding circuit may select an amplitude, frequency or phase of the data symbol from a plurality of predetermined amplitudes, frequencies or phases, to encode the plurality of bits as the selected amplitude, frequency or phase. The communication circuit also may include a receive circuit to receive one or more second data symbols from the isolator, a decoding circuit to decode a plurality of bits of an output data packet as a function of a characteristic of the second data symbol, and a deframing circuit to deframe the output data packet into output data of a plurality of output data channels.

An embodiment of a communication circuit for communicating data across an isolation barrier may include an input circuit to receive a plurality of input data channels, a framing circuit to frame an input data packet from the plurality of input data channels, an encoding circuit to select a characteristic of a data symbol to represent a plurality of bits of the framed input data packet, and a driver circuit to drive one or more data symbols representing the framed input data packet onto an isolator configured to communicate data across the isolation barrier. The encoding circuit may select an amplitude, frequency or phase of the data symbol from a plurality of predetermined amplitudes, frequencies or phases, to encode the plurality of bits as the selected amplitude, frequency or phase. The communication circuit also may include a receive circuit to receive one or more second data symbols from the isolator, a decoding circuit to decode a plurality of bits of an output data packet as a function of a characteristic of the second data symbol, and a deframing circuit to deframe the output data packet into output data of a plurality of output data channels.

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.

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.

A DC-DC converter includes: an transformer having a primary winding and a secondary winding magnetically coupled to the primary winding; a power oscillator applying an oscillating signal to the primary to transmit a power signal to the secondary winding; a rectifier connected to the secondary winding of the transformer to obtain an output DC voltage by rectification of the power signal; comparison circuitry to generate an error signal representing a difference between the output DC voltage and a reference voltage; a transmitter connected to the secondary winding of the transformer to apply an amplitude modulation to the power signal at the secondary winding of the transformer in response to the error signal to thereby produce an amplitude modulated signal at the primary winding; and a receiver and control circuit connected to the primary winding to control an amplitude of the oscillating signal as a function of the amplitude modulated signal.

A DC-DC converter includes: an transformer having a primary winding and a secondary winding magnetically coupled to the primary winding; a power oscillator applying an oscillating signal to the primary to transmit a power signal to the secondary winding; a rectifier connected to the secondary winding of the transformer to obtain an output DC voltage by rectification of the power signal; comparison circuitry to generate an error signal representing a difference between the output DC voltage and a reference voltage; a transmitter connected to the secondary winding of the transformer to apply an amplitude modulation to the power signal at the secondary winding of the transformer in response to the error signal to thereby produce an amplitude modulated signal at the primary winding; and a receiver and control circuit connected to the primary winding to control an amplitude of the oscillating signal as a function of the amplitude modulated signal.

A method for distortion compensation in a transmission link comprising obtaining information of an amplitude distribution of a signal prior to being transmitted by a transmitter, receiving the transmitted signal at a receiver and determining a received signal amplitude distribution, comparing the received signal amplitude distribution to the amplitude distribution of the signal prior to transmission and using results of the comparison to estimate the AM/AM non-linearity in the transmitter.

A method for distortion compensation in a transmission link comprising obtaining information of an amplitude distribution of a signal prior to being transmitted by a transmitter, receiving the transmitted signal at a receiver and determining a received signal amplitude distribution, comparing the received signal amplitude distribution to the amplitude distribution of the signal prior to transmission and using results of the comparison to estimate the AM/AM non-linearity in the transmitter.

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.