Methods, apparatuses, and computer-readable medium for DPD are provided. An example method may include receiving, from a base station, an uplink grant associated with one or more resources. The example method may further include transmitting, to the UE via the one or more resources, a DPD training signal at a first port of a plurality of ports. The example method may further include receiving, at a second port of the plurality of ports, the DPD training signal.

A wireless transceiver. The transceiver includes: (i) a transmit signal path; (ii) a calibration path, comprising a conductor to connect a calibration tone into the transmit signal path; (iii) a receive signal path, comprising a first data signal path to process a first data and a second data signal path, different than the first data signal path, to process a second data; (iv) a first capacitive coupling to couple a response to the calibration tone from the transmit signal path to the first data signal path; and (v) a second capacitive coupling to couple a response to the calibration tone from the transmit signal path to the second data signal path.

A wireless communication device includes an antenna, a DPDC, an amplifier, a coupler, and a bias output unit. The DPDC performs distortion compensation on a transmission signal based on a feedback signal. The amplifier amplifies the transmission signal subjected to the distortion compensation by the DPDC. The coupler splits the transmission signal amplified by the amplifier into a transmission signal output to the antenna and the feedback signal input to the DPDC. The DPDC measures an index based on a reflected wave obtained by reflection of the transmission signal split by the coupler from the antenna. The bias output unit applies a bias voltage for controlling an efficiency of an amplifier to the amplifier in accordance with the index measured by the DPDC.

Various embodiments of the present disclosure relate to transmitter systems, methods, and instructions for signal predistortion. The transmitter system includes an intermodulation distortion (IMD) filter module configured to filter a detected feedback signal (Y.sub.in) to generate a targeted filtered signal (Y.sub.out), a digital pre-distortion (DPD) coefficient estimation module configured to update signal generation coefficients based on comparing an input signal (S.sub.in) with the targeted filtered signal (Y.sub.out), and a distortion compensation processing module configured to generate a pre-distorted signal (U.sub.out) based on the input signal (S.sub.in) using the updated signal generation coefficients.

Various embodiments of the present disclosure relate to transmitter systems, methods, and instructions for signal predistortion. The transmitter system includes a signal decomposition module configured to extract a low-frequency signal (S.sub.lo) and a high-frequency signal (S.sub.hi) from an input signal (S.sub.in); a distortion compensation processing module configured to generate a pre-distorted low-frequency signal (U.sub.lo) and a pre-distorted high-frequency signal (U.sub.hi) based on the received low-frequency and high-frequency signals using signal generation coefficients; a signal combining module configured to combine the pre-distorted low-frequency signal (U.sub.lo) and the pre-distorted high-frequency signal (U.sub.hi); and a signal characteristic estimation processing module configured to update the signal generation coefficients used by the distortion compensation processing module based on comparing the low-frequency signal (S.sub.lo) and the high-frequency signal (S.sub.hi) with a detected feedback low-frequency signal (Y.sub.lo) and a detected feedback high-frequency signal (Y.sub.hi).

The present disclosure relates to a digital frontend system for a radio device comprising a digital filter arranged for receiving digital quadrature signals and for filtering the digital quadrature signals and for outputting filtered quadrature signals; a conversion circuit arranged for receiving the filtered quadrature signals and for performing a rectangular to polar conversion of the filtered quadrature signals and for outputting a plurality of polar signals, characterized in that, the plurality of polar signals comprising an amplitude signal and quadrature phase signals.

The present disclosure relates to correction apparatus and correction methods. One example correction apparatus includes a first adjustment module, a plurality of second adjustment modules, a correction calculation module, and a plurality of non-ideal channels. One second adjustment module is disposed on one non-ideal channel. The first adjustment module is connected to each non-ideal channel. The correction calculation module is separately connected to the first adjustment module and the plurality of second adjustment modules. The correction calculation module is connected to an output end of each non-ideal channel. The non-ideal channel is a channel that outputs an output signal in response to a drive signal having an error value.

A first FFT operator converts, with respect to each of analog circuits, a feedback signal x(t) in the time domain that is obtained after a transmission signal d(t) passes through the analog circuit into a feedback signal X(f) in the frequency domain. A second FFT operator converts the transmission signal in the time domain into a transmission signal D(f) in the frequency domain. A phase error calculator calculates, with respect to each of the analog circuits, a phase error C(f) in the frequency domain based on the feedback signal X(f) and the transmission signal D(f). An IFFT operator calculates, with respect to each of the analog circuits, a tap coefficient c(t) of an FIR filter based on the phase error C(f). The FIR filter 21 filters, with respect to each of the analog circuits, the transmission signal d(t) based on the tap coefficient c(t).

The present disclosure provides a data transmission method including: receiving a first-mode optical signal from a first port corresponding to a first port number; converting, according to a correspondence between the first port number and a first mode group number, the received first-mode optical signal into a second-mode optical signal carried in a first mode group identified by the first mode group number, where the second-mode optical signal carried in the first mode group identified by the first mode group number includes an optical signal in one or more modes; and outputting the second-mode optical signal obtained by means of conversion.

Non-linear interference cancellation techniques are provided for wireless transceivers. Non-linear reduction of interference of a transmit signal on a received signal in a transceiver device, comprises applying the transmit signal to a first non-linear system; applying the received signal to a second non-linear system; and subtracting an output of the first non-linear system output from an output of second non-linear system output to produce an interference mitigated received signal. The first non-linear system and/or the second non-linear system can be implemented using one or more of a Volterra series and a Generalized Memory Polynomial Model. System parameters of the first non-linear system and/or the second non-linear system are adapted to reduce a power of the interference mitigated received signal.