Transceiver arrangement, communication device, method and computer program

A communication device, capable of frequency division duplex communication via a communication network, comprising:

• a transceiver arrangement;
• wherein the transceiver arrangement comprises:
• a receiver configured for frequency-division duplex communication with the communication network;
• a transmitter configured for frequency-division duplex communication with the communication network;
• a transmission port for connecting to an antenna or wire;
• a first filter connected between an output of the transmitter and the transmission port, the first filter configured to pass signals at a transmitter frequency and attenuate signals at a receiver frequency;
• a transformer having a primary winding and a secondary winding, wherein the primary winding has one of its terminals connected to the transmission port;
• a second filter connected between another of the terminals of the primary winding and a reference voltage, the second filter configured to attenuate signals at the transmitter frequency and pass signals at the receiver frequency;
• an adaptive impedance circuit configured to provide an adjustable resistance, the adaptive impedance circuit connected between the output of the transmitter and a junction between the second filter and the another of the terminals of the primary winding, the adaptive impedance circuit configured to provide a contribution from the transmitter to the primary winding such that a common-mode rejection of a contribution from the transmitter provided at the transmission port occurs at the receive frequency.

A method of controlling a transceiver arrangement;

• the transceiver arrangement comprising a receiver and a transmitter configured for frequency-division duplex communication with a communication network, a transmission port for connecting to an antenna or wire, a first filter connected between an output of the transmitter and the transmission port, the first filter configured to pass signals at a transmitter frequency and attenuate signals at a receiver frequency, a transformer having a primary winding and a secondary winding, wherein the primary winding has one of its terminals connected to the transmission port, a second filter connected between another of the terminals of the primary winding and a reference voltage, the second filter configured to attenuate signals at the transmitter frequency and pass signals at the receiver frequency, and an adaptive impedance circuit configured to provide an adjustable resistance, the adaptive impedance circuit connected between the output of the transmitter and a junction between the second filter and the another of the terminals of the primary winding, the adaptive impedance circuit configured to provide a contribution from the transmitter to the primary winding such that a common-mode rejection of a contribution from the transmitter provided at the transmission port occurs at receive frequency;
• wherein the method comprises:
• setting filter parameters such that:
• the first filter passes signals at the transmitter frequency and attenuates signals at the receiver frequency;
• and
• the second filter attenuates signals at the transmitter frequency and passes signals at the receive frequency;
• adjusting the adjustable resistance of the adaptive impedance circuit such that magnitude of transmitter contribution in the primary winding is reduced;
• and
• phase tuning at least one impedance element of at least one of the first filter, the second filter, and the adaptive impedance circuit, such that an amplitude is minimized.

A computer program product stored in a non-transitory computer readable medium for controlling a transceiver arrangement;

• the transceiver arrangement comprising a receiver and a transmitter configured for frequency-division duplex communication with a communication network, a transmission port for connecting to an antenna or wire, a first filter connected between an output of the transmitter and the transmission port, the first filter configured to pass signals at a transmitter frequency and attenuate signals at a receiver frequency, a transformer having a primary winding and a secondary winding, wherein the primary winding has one of its terminals connected to the transmission port, a second filter connected between another of the terminals of the primary winding and a reference voltage, the second filter configured to attenuate signals at the transmitter frequency and pass signals at the receiver frequency, and an adaptive impedance circuit configured to provide an adjustable resistance, the adaptive impedance circuit connected between the output of the transmitter and a junction between the second filter and the another of the terminals of the primary winding, the adaptive impedance circuit configured to provide a contribution from the transmitter to the primary winding such that a common-mode rejection of a contribution from the transmitter provided at the transmission port occurs at receive frequency;
• the computer program product comprising software instructions which, when run on a processing circuit of the a processing circuit of a transceiver arrangement, causes the processing circuit to:
• set filter parameters such that:
• the first filter passes signals at the transmitter frequency and attenuates signals at the receiver frequency;
• and
• the second filter attenuates signals at the transmitter frequency and passes signals at the receive frequency;
• adjust the adjustable resistance of the adaptive impedance circuit such that magnitude of transmitter contribution in the primary winding is reduced;
• and
• phase tune at least one impedance element of at least one of the first filter, the second filter, and the adaptive impedance circuit, such that an amplitude is minimized.