The present disclosure relates to a concept for a transformer, a transmitter circuit, a semiconductor chip, a semiconductor package, a base station, a mobile device and a method for a radio frequency transmitter. The transformer for a radio frequency transmitter circuit comprises a primary coil and a secondary coils, which are configured to receive an input signal and to provide an output signal, and a ternary coil configured to provide a feedback signal.

A signal isolation control apparatus for controlling duplexing of signals to be transmitted through and received from an antenna. The apparatus includes a transmitter chain tap input for coupling to a transmitter chain. An auxiliary transmitter chain is operably coupled to the transmitter chain tap input for processing a transitory signal tapped from the transmitter chain, the auxiliary transmitter chain including an adaptive filter unit and a balance node output for operably coupling to a balance node of a hybrid junction. The adaptive filter unit has a signal leakage monitoring input for operably coupling to an output node of the hybrid junction. The auxiliary transmitter chain is arranged to process the tapped transitory signal in order to generate and apply an isolation signal at the balance node output for maximizing isolation of an output node of the hybrid junction from an input node of the hybrid junction.

A duplexing apparatus comprises a reference of impedance settings and corresponding calibration measurements. A controller is arranged to set a variable impedance to a first impedance setting and transmit a first transmit signal at a first transmit frequency and measure a resulting first signal at an output node of a hybrid circuit. The controller then selects a second impedance setting, transmits a second transmit signal at a second transmit frequency and measures a resulting second signal at the output node. The controller then determines a balancing result using a system of equations associating the first and second measured signals, and first and second calibration measurements from the reference in respect of the first and second impedance settings, respectively. A third impedance setting is retrieved from the reference by reference to the balancing result to provide isolation of an input node from the output node of the hybrid circuit.

A receiving circuit includes a first inductor, a second inductor, a capacitor and an amplifier. The first inductor includes a first terminal and a second terminal. The second inductor includes a third terminal and a fourth terminal. The first terminal is configured to couple with an antenna for receiving a first electrical signal corresponding to an electromagnetic wave received by the antenna. The second terminal is configured to output a second electrical signal based on the first electrical signal. The first capacitor includes a fifth terminal coupled to the third terminal and a sixth terminal coupled to the fourth terminal. The amplifier is coupled to the second terminal and configured to amplify the second electrical signal.

A receiving circuit includes a first inductor, a second inductor, a capacitor and an amplifier. The first inductor includes a first terminal and a second terminal. The second inductor includes a third terminal and a fourth terminal. The first terminal is configured to couple with an antenna for receiving a first electrical signal corresponding to an electromagnetic wave received by the antenna. The second terminal is configured to output a second electrical signal based on the first electrical signal. The first capacitor includes a fifth terminal coupled to the third terminal and a sixth terminal coupled to the fourth terminal. The amplifier is coupled to the second terminal and configured to amplify the second electrical signal.

In a circularly polarized wave antenna apparatus including a non-reciprocal transmission line apparatus having forward and backward propagation constants different from each other, the non-reciprocal transmission line apparatus includes a transmission line part for a microwave, a series branch circuit equivalently including a capacitive element, and a shunt branch circuit branched from the transmission line part and equivalently includes an inductive element. The non-reciprocal transmission line apparatus is formed in a nonlinear shape and magnetized in a magnetization direction different from a propagation direction of the microwave. The non-reciprocal transmission line apparatus includes first and second reflectors provided at both ends of the non-reciprocal transmission line apparatus, respectively, and reflecting a signal; and satisfies that a phase difference between each pair of line parts located at positions opposed to each other across a substantially central part of the non-reciprocal transmission line apparatus is substantially 180 degrees.

The present disclosure relates to a telecommunications device. The telecommunications device includes an electrical balance duplexer connected to an output node of a transmission path, an input node of a receive path, an antenna, and a tunable impedance. The electrical balance duplexer is configured to isolate the transmission path from the receive path by tuning the tunable impedance. The telecommunications device also includes a tuning circuit for tuning the tunable impedance. The tuning circuit includes amplitude detectors for measuring voltage amplitudes, phase detectors for measuring voltage phase differences, an impedance sensor for measuring an input impedance of the electrical balance duplexer, and a processing unit operatively connected to the detectors, the impedance sensor, and the tunable impedance. The processing unit is configured to calculate an optimized impedance value. The processing unit is also configured to tune the tunable impedance towards the optimized impedance value.

A signal isolation control apparatus for controlling duplexing of signals to be transmitted through and received from an antenna. The apparatus includes a transmitter chain tap input for coupling to a transmitter chain. An auxiliary transmitter chain is operably coupled to the transmitter chain tap input for processing a transitory signal tapped from the transmitter chain, the auxiliary transmitter chain including an adaptive filter unit and a balance node output for operably coupling to a balance node of a hybrid junction. The adaptive filter unit has a signal leakage monitoring input for operably coupling to an output node of the hybrid junction. The auxiliary transmitter chain is arranged to process the tapped transitory signal in order to generate and apply an isolation signal at the balance node output for maximising isolation of an output node of the hybrid junction from an input node of the hybrid junction.

A duplexer-less transceiver arrangement is disclosed. The transceiver comprises a receiver configured for frequency-division duplex communication with a communication network; a transmitter configured for frequency-division duplex communication with the communication network; an antenna port for connecting to an antenna; a balancing impedance circuit arranged to provide an adaptive impedance arranged to mimic the impedance at the antenna port; and an impedance network differentially connecting the receiver, transmitter, antenna port and balancing impedance circuit, wherein the impedance network includes a cross-connection.

A duplexer-less transceiver arrangement is disclosed. The transceiver comprises a receiver configured for frequency-division duplex communication with a communication network; a transmitter configured for frequency-division duplex communication with the communication network; an antenna port for connecting to an antenna; a balancing impedance circuit arranged to provide an adaptive impedance arranged to mimic the impedance at the antenna port; and an impedance network differentially connecting the receiver, transmitter, antenna port and balancing impedance circuit, wherein the impedance network includes a cross-connection.