A wireless communication apparatus includes a first conductor and a second conductor that function as a set of electrodes for wireless communication, a third conductor and a fourth conductor that function as another set of electrodes for wireless communication. A difference between a first distance between a centroid of the first conductor and a centroid of the third conductor and a second distance between a centroid of the second conductor and the centroid of the third conductor is less than a width of the first conductor and a width of the second conductor. A third distance between the centroid of the first conductor and a centroid of the fourth conductor is longer than the first distance. A fourth distance between the centroid of the second conductor and the centroid of the fourth conductor is longer than the second distance.

A wireless communication apparatus includes a first conductor and a second conductor that function as a set of electrodes for wireless communication, a third conductor and a fourth conductor that function as another set of electrodes for wireless communication. A difference between a first distance between a centroid of the first conductor and a centroid of the third conductor and a second distance between a centroid of the second conductor and the centroid of the third conductor is less than a width of the first conductor and a width of the second conductor. A third distance between the centroid of the first conductor and a centroid of the fourth conductor is longer than the first distance. A fourth distance between the centroid of the second conductor and the centroid of the fourth conductor is longer than the second distance.

A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying element; a second amplifying element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying element, another end of the primary coil is connected to an output terminal of the second amplifying element, an end of the secondary coil is connected to an output terminal of the power amplifier, the first amplifying element and the second amplifying element are disposed on the first principal surface, and the first circuit component is disposed on the second principal surface.

A method for providing nonlinear self-interference cancellation of a wireless communication device includes: receiving digital samples of an interfering signal having a first sampling rate and a corrupted victim signal having a second sampling rate; generating a kernel vector based on the interfering signal, wherein the kernel vector has terms of nonlinear self-interference; estimating the nonlinear self-interference of the corrupted victim signal using the terms of the nonlinear self-interference; and providing an estimation of a desired signal by cancelling the nonlinear self-interference from the corrupted victim signal.

A method for providing nonlinear self-interference cancellation of a wireless communication device includes: receiving digital samples of an interfering signal having a first sampling rate and a corrupted victim signal having a second sampling rate; generating a kernel vector based on the interfering signal, wherein the kernel vector has terms of nonlinear self-interference; estimating the nonlinear self-interference of the corrupted victim signal using the terms of the nonlinear self-interference; and providing an estimation of a desired signal by cancelling the nonlinear self-interference from the corrupted victim signal.

A wireless communication module includes a first conductor and a second conductor that function as an electrode for wireless communication of a differential signal using electric field coupling, a third conductor and a fourth conductor that function as an electrode for wireless communication using electric field coupling. A straight line that connects the centroid of the first conductor and the centroid of the second conductor is not parallel to a straight line that connects the centroid of the third conductor and the centroid of the fourth conductor.

A wireless communication module includes a first conductor and a second conductor that function as an electrode for wireless communication of a differential signal using electric field coupling, a third conductor and a fourth conductor that function as an electrode for wireless communication using electric field coupling. A straight line that connects the centroid of the first conductor and the centroid of the second conductor is not parallel to a straight line that connects the centroid of the third conductor and the centroid of the fourth conductor.

A transceiver system is configured to concurrently send TX signals and receive RX signals on an antenna system in the same frequency band. A bi-directional frequency converter circuit modulates the TX signals and RX signals by a modulation frequency. The modulated TX signals and RX are frequency shifted so that they have different frequencies that are not in the same frequency band. For example, the TX signal may be shifted to a higher frequency and the RX signal may be shifted to a lower frequency. Filters can then be used to isolate the TX signal and the RX signal for transmission and/or processing.

A transceiver system is configured to concurrently send TX signals and receive RX signals on an antenna system in the same frequency band. A bi-directional frequency converter circuit modulates the TX signals and RX signals by a modulation frequency. The modulated TX signals and RX are frequency shifted so that they have different frequencies that are not in the same frequency band. For example, the TX signal may be shifted to a higher frequency and the RX signal may be shifted to a lower frequency. Filters can then be used to isolate the TX signal and the RX signal for transmission and/or processing.

A radio frequency (RF) front end for wireless communications, in particular for use in a half duplex (HD) and/or full duplex (FD) transceiver. The RF front end is based on a quadrature balanced power amplifier (QBPA). The RF front end includes an antenna port for outputting a transmit signal to and receiving a receive signal from an antenna, and a receive port for outputting the receive signal to a signal processing section. Further, the QBPA is configured to receive a transmit input signal at a first port, receive a cancellation input signal at a fourth port, and receive the receive signal at a second port coupled to the antenna port.