A system includes a balun, a power monitoring circuit, a first circuit, and a second circuit. The balun includes a first inductor to receive an input and a second inductor to couple the input to a load. The power monitoring circuit is configured to monitor an amount of power being delivered to the load when the input is coupled to the load. The first circuit is configured to couple an entire of the second inductor to the first inductor when a first power is delivered to the load. The second circuit is configured to couple a portion of the second inductor to the first inductor when a second power that is less than the first power is delivered to the load.

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 duplexer-less transceiver arrangement (300) is disclosed. The transceiver comprises a receiver (302) arranged for frequency-division duplex communication with a communication network; a transmitter (304) arranged for frequency-division duplex communication with the communication network; an antenna port (306) for connecting to an antenna; a balancing impedance circuit (308) arranged to provide an adaptive impedance arranged to mimic the impedance at the antenna port; and an impedance network differentially connecting the receiver (302), transmitter (304), antenna port (306) and balancing impedance circuit (308), wherein the impedance network includes a cross-connection.

A system includes a balun, a power monitoring circuit, a first circuit, and a second circuit. The balun includes a first inductor to receive an input and a second inductor to couple the input to a load. The power monitoring circuit is configured to monitor an amount of power being delivered to the load when the input is coupled to the load. The first circuit is configured to couple an entire of the second inductor to the first inductor when a first power is delivered to the load. The second circuit is configured to couple a portion of the second inductor to the first inductor when a second power that is less than the first power is delivered to the load.