A signal generation method includes phase-changing baseband signals with respective phase changing patterns to generate respective phase-changed signals, each of the phase changing patterns being different from each other, and inverse-fast-Fourier-transforming the phase-changed signals to respective orthogonal frequency division multiplexing (OFDM) transmission signals. Each phase changing pattern has N candidates for an amount of change in a phase, N being an integer greater than two, and each candidate is periodically selected from the N candidates based on subcarriers of the respective OFDM transmission signals, a phase of the respective baseband signals being changed by the each candidate.

A receiver circuit is disclosed. The receiver circuit includes an amplifier configured to generate an RF signal based on a received signal, where the RF signal includes an information signal and a blocker signal modulating an RF carrier frequency. The receiver circuit also includes an RF filter connected to the amplifier, where the RF filter is configured to selectively attenuate the blocker signal.

Provided is a distortion compensation device performing distortion compensation on a signal to be amplified by an amplifier, of which an internal state affecting a distortion characteristic varies, using a distortion compensation model, wherein the distortion compensation model includes a plurality of calculation models having respective distortion compensation characteristic for the amplifier in different internal states, and a combiner combining the plurality of calculation models at a combination ratio corresponding to the internal state that varies.

Methods, devices and algorithms for the linearization of nonlinear time variant systems and the synchronization of a plurality of such systems. One embodiment includes a transmit path, including the power amplifier, as used in wireless transmit systems. Advances made in CMOS technology, digital to analog converter (DAC) technology make it possible to implement a substantial part of such a system in the digital domain. Additional embodiments include the integration of a substantial part of such a transmit system in a single integrated circuit (IC). A digital implementation allows for linearization of a broad range of nonlinear and time variant effects. Another aspects is the reuse of methods, devices, components and algorithms used for the linearization of a transmit system to synchronize and time align multiple transmit systems.

Embodiments of the present disclosure relate to a device, method and computer readable storage medium for wireless data transmission. In example embodiments, the device includes a first NCO configured to shift a frequency of a pre-distorted downlink baseband signal by a first offset to generate a first signal. The baseband signal is associated with a plurality of allocated carriers. The device also includes an RF processing unit including an LO configured to generate an LO signal at an LO frequency. The LO frequency is within a protection area of one of the plurality of allocated carriers or equal to a center frequency of the one of the plurality of allocated carriers. The device also includes a power amplifier configured to generate, based on a modulated baseband signal, an amplified signal for transmission. The device also includes a second NCO configured to shift a frequency of the amplified signal by a second offset to generate a second signal for generation of a pre-distortion coefficient.

A method in an adaptive filter system is provided. The method comprises obtaining parameters for a plurality of branches of the adaptive filter system. The method further comprises computing gradient-based information for a selected one of the plurality of branches. The method further comprises updating the parameters for the plurality of branches based on the gradient-based information for the selected branch. An adaptive filter system is also provided.

An Analog-to-Digital Converter, ADC, system is provided. The ADC system comprises a plurality of ADC circuits and a first input for receiving a transmit signal of a transceiver. One ADC circuit of the plurality of ADC circuits is coupled to the first input and configured to provide first digital data based on the transmit signal. The ADC system further comprises a second input for receiving a receive signal of the transceiver. The other ADC circuits of the plurality of ADC circuits are coupled to the second input, wherein the other ADC circuits of the plurality of ADC circuits are time-interleaved and configured to provide second digital data based on the receive signal. Additionally, the ADC system comprises a first output configured to output digital feedback data based on the first digital data, and a second output configured to output digital receive data based on the second digital data.

An input signal has a desired signal component and an interfering signal component superimposed thereon. Interfering component estimation processing is applied to the input signal, obtaining as a result a filtered signal comprising a sequence of filtered data samples. The filtered signal is subtracted from the input signal obtaining as a result an output signal comprising a sequence of output data samples. The interfering component estimation processing applies conjugating processing to the input signal, providing a conjugated version of the input signal. An adaptive signal processing coefficient is computed and adaptive signal processing is applied to the conjugated version of the input signal using the adaptive processing coefficient.

An Analog-to-Digital Converter, ADC, system is provided. The ADC system comprises a plurality of ADC circuits and a first input for receiving a transmit signal of a transceiver. One ADC circuit of the plurality of ADC circuits is coupled to the first input and configured to provide first digital data based on the transmit signal. The ADC system further comprises a second input for receiving a receive signal of the transceiver. The other ADC circuits of the plurality of ADC circuits are coupled to the second input, wherein the other ADC circuits of the plurality of ADC circuits are time-interleaved and configured to provide second digital data based on the receive signal. Additionally, the ADC system comprises a first output configured to output digital feedback data based on the first digital data, and a second output configured to output digital receive data based on the second digital data.

A wireless communication apparatus includes: a processor that performs distortion compensation on a complex number transmission signal by using a distortion compensation coefficient; a power amplifier that amplifies the transmission signal subjected to distortion compensation by the processor; and a feedback path that feeds back a signal output from the power amplifier to supply a real number feedback signal to the processor. The processor executes a process including: estimating a complex number feedback signal by performing linear computation on the complex number transmission signal and the real number feedback signal; and updating the distortion compensation coefficient by using the estimated complex number feedback signal.