Telefonaktiebolaget Lm Ericsson (publ)

Daniel Eckerbert

Stefan Mikael Andersson

Imad Ud Din

Henrik Sjöland

Johan Wernehag

Tobias Tired

Fredrik Tillman

Johan Wernerhag

Stefan Andersson

A transceiver suitable for frequency division duplex (FDD) communication is disclosed. In one exemplary embodiment, a transmitter leakage reduction circuit for a transceiver is described. The transmitter leakage reduction circuit comprises an auxiliary power amplifier, first and second filters, and a signal transmission arrangement. The auxiliary power amplifier is configured to provide an auxiliary power amplifier output signal that represents an output signal of a power amplifier of the transmitter with a controllable phase shift or gain output. The first and second filters are configured to attenuate any signals in the receive frequency band of the respective power amplifier output signal and auxiliary power amplifier output signal. The signal transmission arrangement is configured to suppress a contribution of the power amplifier output signal from a signal received from an RF connecting point using the auxiliary power amplifier output signal to obtain a received signal that is input to the receiver.

Transmitter receiver leakage reduction in a full duplex system without the use of a duplexer

A transceiver suitable for frequency duplex division communication is disclosed. The transceiver comprises a transmitter, wherein the transmitter comprises a power amplifier; a receiver; an auxiliary power amplifier which is arranged to provide a controllable phase shift and gain output; a first filter arranged at an output of the power amplifier arranged to attenuate frequencies at a receiving frequency of the receiver; a second filter arrangement at an output of the auxiliary power amplifier arranged to attenuate frequencies at a receiving frequency of the receiver; and a signal transmission arrangement. The signal transmission arrangement is arranged to transmit signals provided from the transmitter through its power amplifier to a radio frequency, RF, connecting point, receive signals from the RF connecting point and provide the signals to the receiver, and provide signals from the auxiliary amplifier towards an input of the receiver. The transceiver also comprises a controller, wherein the controller is arranged to control the auxiliary power amplifier output to provide a signal that has a phase and amplitude in relation to the output of the power amplifier of the transmitter such that the transmitter contribution to the signal at the input of the receiver is suppressed. A method of controlling the transceiver, a communication device and computer program are also disclosed.

A transceiver arrangement comprises a receiver arranged for frequency-division duplex communication with a communication network; a transmitter arranged 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 and arranged to pass signals at transmitter frequency and attenuate signals at 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 and arranged to attenuate signals at transmitter frequency and pass signals at receiver frequency; and an adaptive impedance circuit arranged to provide an adjustable resistance, connected between the output of the transmitter and the junction between the second filter and the another of the terminals of the primary winding, and arranged 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. A communication device, a method of controlling a transceiver arrangement, and a computer program are also disclosed.

Transceiver arrangement, communication device, method and computer program

A transceiver front-end of a communication device comprises a frequency blocking arrangement, which may be either a transmit frequency blocking arrangement or a receive frequency blocking arrangement. The frequency blocking arrangement has a blocking frequency interval associated with one of a transmit frequency and receive frequency, and a non-blocking frequency interval associated with the other of the transmit frequency and receive frequency. The frequency blocking arrangement is configured to block passage of signals in the blocking frequency interval between said signal transmission and reception node and either said receiver node or said transmitter node. The frequency blocking arrangement comprises a network of passive components comprising at least one transformer and a filter arrangement adapted to have a higher impedance value in the blocking frequency interval than in the non-blocking frequency interval.

Transceiver front-end

A transceiver front-end for a communication device comprises a transmit frequency blocking arrangement and a receive frequency blocking arrangement. The transmit frequency blocking arrangement has a blocking frequency interval associated with the transmit frequency and a non-blocking frequency interval associated with the receive frequency, and is configured to block passage of transmit frequency signals between the signal transmission and reception arrangement and the receiver. The receive frequency blocking arrangement has a blocking frequency interval associated with the receive frequency and a non-blocking frequency interval associated with the transmit frequency, and is configured to block passage of receive frequency signals between the signal transmission and reception arrangement and the transmitter. One of the frequency blocking arrangements comprises a network of passive components including at least one transformer and a filter arrangement with a higher impedance at the blocking frequency interval than at the non-blocking frequency interval.

A method of frequency down-converting an input signal to an output signal, a first local oscillator signal is generated as a square wave having a duty cycle of 1/3 or 2/3, and the input signal is mixed with first oscillator signal to achieve a first down-converted signal, a second local oscillator signal is generated as a modified square wave having the same period time as the first oscillator signal and a duty cycle of 2/3, of which one part has a positive amplitude and another part has a negative amplitude. The input signal is mixed with the second oscillator signal to achieve a second down-converted signal. The first oscillator signal has a delay of 1/4 of the period time to achieve a phase shift of &#x3c0;/2 between the oscillator signals, and at least one down-converted signal is multiplied by a pre-calculated factor. The resulting down-converted signals are added to achieve the output signal.

Growing community of inventors

Landskrona, Sweden

Daniel Eckerbert