A direct radiation wireless digital communication system based on a digital programmable metamaterial, including a transmitting system and a receiving system, where information transmitted by the transmitting system is loaded to a programmable metamaterial, and is directly radiated into free space in a form of an ever-changing far-field pattern under the illumination of a feeding antenna; the receiving system collects electric field values received by receiving antennas located at different positions of a far-field region to obtain a far-field pattern, and recovers the transmitted original information according to a mapping relationship between the far-field pattern and a coding sequence. The system does not require a digital-to-analog conversion module and a frequency mixing module. The system also features an inherent secrete communication in the physical level which protects the transmitted information from being intercepted at a single point or any random points, and has the capabilities of self-adaption and self-perception.

Provided is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals to be transmitted over the same frequency bandwidth at the same time, including the steps of selecting a matrix F[i] from among N matrices, which define precoding performed on the plurality of baseband signals, while switching between the N matrices, i being an integer from 0 to N−1, and N being an integer at least two, generating a first precoded signal z1 and a second precoded signal z2, generating a first encoded block and a second encoded block using a predetermined error correction block encoding method, generating a baseband signal with M symbols from the first encoded block and a≠baseband signal with M symbols the second encoded block, and precoding a combination of the generated baseband signals to generate a precoded signal having M slots.

A method of encoding input data. The method includes receiving a plurality of data bits of a bit stream. The method further includes forming words using the plurality of data bits to create a plurality of data packets including a first data packet. The method further includes encoding the words of the first data packet into coded words, partitioning the coded words into a plurality of blocks of M words each and integrating the coded words in each block in an interleaved order to generate a coded data packet for transmission through a communication channel.

Methods are described allowing a vector signaling code to encode multi-level data without the significant alphabet size increase known to cause symbol dynamic range compression and thus increased noise susceptibility. By intentionally restricting the number of codewords used, good pin efficiency may be maintained along with improved system signal-to-noise ratio.

Using a transformation based at least in part on a non-simple orthogonal or unitary matrix, data may be transmitted over a data bus in a manner that is resilient to one or more types of signal noise, that does not require a common reference at the transmission and acquisition points, and/or that has a pin-efficiency that is greater than 50% and may approach that of single-ended signaling. Such transformations may be implemented in hardware in an efficient manner. Hybrid transformers that apply such transformations to selected subsets of signals to be transmitted may be used to adapt to various signal set sizes and/or transmission environment properties including noise and physical space requirements of given transmission environments.

A device and method for a receiver configured to perform timing recovery decoupled feed-forward equalizer (FFE) adaptation. The receiver device can include an analog front-end (AFE) device, which is coupled to a time-interleaved (TI) interface. The TI interface is coupled in a timing recovery feedback loop to FFE equalizers, a digital signal processor (DSP), a delay timing loop (DTL) device, and a clock device, which feeds back to the TI interface. The DSP has an additional pathway to the FFE equalizers, which has an additional pathway to the DTL device. The DTL loop is equipped with an interleave specific enable/disable vector Q[1:N] that can turn on/off the contribution of the specific time interleave errors to the timing recovery loop, which allows the FFE adaptation process to be decoupled from the timing recovery loop.

A communication system has a galvanic isolation link coupling a first circuit to a second circuit. The first circuit transmits first data signals to the second circuit and receives second data signals from the second circuit in response to the first data signals. The data signals are transmitted in consecutive time slots of a determined time duration via the galvanic isolation link. The first data signals include polling signals transmitted from the first circuit to the second circuit during consecutive time slots, and on-demand access requests transmitted from the first circuit to the second circuit. The second data signals include status response signals transmitted from the second circuit to the first circuit in response to polling signals received from the first circuit, and access response signals transmitted from the second circuit to the first circuit in response to access requests received from the first circuit.

Methods are described allowing a vector signaling code to encode multi-level data without the significant alphabet size increase known to cause symbol dynamic range compression and thus increased noise susceptibility. By intentionally restricting the number of codewords used, good pin efficiency may be maintained along with improved system signal-to-noise ratio.

A digital isolator provided includes a pair of transceiver circuits and a control circuit. Each transceiver circuit includes a transmitter circuit, a receiver circuit, and a DC isolation circuit. When the control circuit controls one of the pair of transceiver circuits to operate in a transmitting mode and the other of the pair of transceiver circuits to operate in a receiving mode, the transmitting circuit of the transceiver circuit operating in the transmitting mode receives a square wave signal to generate a pair of differential square wave signals, the connected DC isolation circuits receive the pair of differential square wave signals to generate a pair of differential coupling signals, and the transceiver circuit operating in the receiving mode uses the pair of differential coupling signals to output the square wave signal through the design of a pair of feedback voltage divider circuits and a differential comparison circuit included therein.

A data modulator for a transmitter includes a multiplexer configured to receive, at a first rate, a first data stream including a plurality of first symbols and a second data stream including a plurality of second symbols. The multiplexer is configured to selectively output, based on a first clock signal, the plurality of first symbols and the plurality of second symbols to form a third data stream that achieves a second rate greater than the first rate for transmission of the third data stream by the transmitter.