Abstract: Examples relate to a concept for a Radio-Frequency (RF) frontend, and for a communication device comprising such an RF frontend. A radio-frequency frontend apparatus comprises a receive branch, comprising circuitry configured to obtain a received signal and a digital pre-distortion feedback signal from an external transceiver device. The radio-frequency frontend apparatus comprises power measurement circuitry configured to generate a first signal that represents a power of the received signal based on the received signal, and to generate a second signal that represents a power of an amplified signal based on the digital pre-distortion feedback signal, the amplified signal being a signal that is amplified by a power amplifier of the external transceiver device.

Abstract: An energy-efficient implementation of a WiFi transceiver is proposed in this disclosure. The WiFi transceiver comprises a receive chain comprising a variable receive (Rx) filter circuit and a variable Rx analog-to-digital converter (ADC) circuit. The receive chain is configured to receive a receive signal during a receive mode of operation, having a receive bandwidth associated therewith and receive a transmit signal associated with a transmit chain of the transceiver during a transmit mode of operation, having a transmit bandwidth associated therewith. The WiFi transceiver further comprises a control circuit configured to dynamically adapt a bandwidth of the variable Rx filter and the variable Rx ADC in the receive chain to the receive bandwidth or to the transmit bandwidth, based on the mode of operation.

Abstract: Examples relate to a concept for a Radio-Frequency (RF) frontend, and for a communication device comprising such an RF frontend. A radio-frequency frontend apparatus comprises a receive branch, comprising circuitry configured to obtain a received signal and a digital pre-distortion feedback signal from an external transceiver device. The radio-frequency frontend apparatus comprises power measurement circuitry configured to generate a first signal that represents a power of the received signal based on the received signal, and to generate a second signal that represents a power of an amplified signal based on the digital pre-distortion feedback signal, the amplified signal being a signal that is amplified by a power amplifier of the external transceiver device.

Abstract: An energy-efficient implementation of a WiFi transceiver is proposed in this disclosure. The WiFi transceiver comprises a receive chain comprising a variable receive (Rx) filter circuit and a variable Rx analog-to-digital converter (ADC) circuit. The receive chain is configured to receive a receive signal during a receive mode of operation, having a receive bandwidth associated therewith and receive a transmit signal associated with a transmit chain of the transceiver during a transmit mode of operation, having a transmit bandwidth associated therewith. The WiFi transceiver further comprises a control circuit configured to dynamically adapt a bandwidth of the variable Rx filter and the variable Rx ADC in the receive chain to the receive bandwidth or to the transmit bandwidth, based on the mode of operation.

Abstract: An energy-efficient implementation of a WiFi transceiver is proposed in this disclosure. The WiFi transceiver comprises a receive chain comprising a variable receive (Rx) filter circuit and a variable Rx analog-to-digital converter (ADC) circuit. The receive chain is configured to receive a receive signal during a receive mode of operation, having a receive bandwidth associated therewith and receive a transmit signal associated with a transmit chain of the transceiver during a transmit mode of operation, having a transmit bandwidth associated therewith. The WiFi transceiver further comprises a control circuit configured to dynamically adapt a bandwidth of the variable Rx filter and the variable Rx ADC in the receive chain to the receive bandwidth or to the transmit bandwidth, based on the mode of operation.

Abstract: An energy-efficient implementation of a WiFi transceiver is proposed in this disclosure. The WiFi transceiver comprises a receive chain comprising a variable receive (Rx) filter circuit and a variable Rx analog-to-digital converter (ADC) circuit. The receive chain is configured to receive a receive signal during a receive mode of operation, having a receive bandwidth associated therewith and receive a transmit signal associated with a transmit chain of the transceiver during a transmit mode of operation, having a transmit bandwidth associated therewith. The WiFi transceiver further comprises a control circuit configured to dynamically adapt a bandwidth of the variable Rx filter and the variable Rx ADC in the receive chain to the receive bandwidth or to the transmit bandwidth, based on the mode of operation.

Abstract: A circuit with a successive approximation analog-to-digital converter utilizes a feedback path and is operated for example in accordance with the successive approximation method. The feedback path is configured to translate a digital signal in accordance with a prescribed function and to furthermore convert the translated digital signal into an analog feedback signal. For example, the prescribed function can be an exponential function. As such, it can be possible to convert an input signal into an output signal by means of a nonlinear characteristic.

Abstract: A circuit comprises a successive approximation analog-to-digital converter that comprises a feedback path and is operated for example in accordance with the successive approximation method. The feedback path is configured to translate a digital signal in accordance with a prescribed function and to furthermore convert the translated digital signal into an analog feedback signal. For example, the prescribed function can be an exponential function. As such, it can be possible to convert an input signal into an output signal by means of a nonlinear characteristic.

Abstract: According to an embodiment, a circuit includes an amplifier and an open-loop control system. The amplifier has an output stage for amplifying a signal, a power supply for driving a supply voltage of the output stage to different voltage levels responsive to being modulated and a pulse width modulator for modulating the power supply responsive to a mask input. The open-loop control system includes a mask generator and a detector. The mask generator is configured to generate the mask input as a function of the envelope of the signal. The detector is configured to detect discontinuities in the mask input and compensate for the discontinuities.

Abstract: A driver circuit for driving a transmit signal for a line includes a signal amplifier configured to deliver a transmit signal, present at a signal input of the signal amplifier, amplified with a gain to a signal output, a line interface circuit connected between the signal output of the signal amplifier and the line, and a hybrid circuit connected to the line interface circuit, the hybrid circuit configured to suppress the transmit signal and couple a received signal received via the line to a signal input of the signal amplifier to provide impedance synthesis.

Abstract: Driver circuit for driving a transmit signal for a line comprising a signal amplifier which delivers a transmit signal, present at a signal input of the signal amplifier, amplified with a gain to a signal output, a line interface circuit which is connected between the signal output of the signal amplifier and the line, and comprising a hybrid circuit which is connected to the line interface circuit, wherein the hybrid circuit suppresses the transmit signal and couples a received signal received via the line to a signal input of the signal amplifier for the purpose of impedance synthesis.

Abstract: According to an embodiment, a circuit includes an amplifier and an open-loop control system. The amplifier has an output stage for amplifying a signal, a power supply for driving a supply voltage of the output stage to different voltage levels responsive to being modulated and a pulse width modulator for modulating the power supply responsive to a mask input. The open-loop control system includes a mask generator and a detector. The mask generator is configured to generate the mask input as a function of the envelope of the signal. The detector is configured to detect discontinuities in the mask input and compensate for the discontinuities.

Abstract: A method and a device for amplifying a reception signal are provided, involving the adjustment of a gain by which the reception signal is amplified, in particular as a function of a signal level of the reception signal. For example, lowpass filtering with a variable cutoff frequency is used to filter out a gain-dependent frequency range of the reception signal, which may especially contain an undesirable echo signal. Such a method and such a device are suitable in particular for the reception of ADSL signals in a central office.

Abstract: Driver circuit for driving a transmit signal for a line comprising a signal amplifier which delivers a transmit signal, present at a signal input of the signal amplifier, amplified with a gain to a signal output, a line interface circuit which is connected between the signal output of the signal amplifier and the line, and comprising a hybrid circuit which is connected to the line interface circuit, wherein the hybrid circuit suppresses the transmit signal and couples a received signal received via the line to a signal input of the signal amplifier for the purpose of impedance synthesis.

Abstract: The present invention relates to a circuit for electronically generating a call impedance in telephone terminals, comprising a call alternating voltage that may be tapped between a first and a second input terminal. The inventive circuit has a regulating device with a programmable digital filter for regulating impedance, wherein the transmission function of the regulating device can be adjusted by programming the filter coefficients of the digital filter. The inventive regulating device makes it possible to adapt the call impedance to different country-specific requirements. To this end, the regulating device has a programmable digital filter that may be embodied as a digital signal processor. In an especially preferred embodiment, the digital filter is implemented in the form of a program in the digital signal processor.

Abstract: The invention relates to a circuit arrangement for forming the termination of an analogous subscriber line which comprises a first connection and a second connection for connecting a twin-wire analogous subscriber line. Said first connection is linked with said second connection via a series connection of a first capacitor, at least one first adjustable resistor and one second capacitor. According to the invention, a direct current source is linked with the first point of linkage of the first capacitor and the first adjustable resistor. Said direct current source impresses a current which serves to adjust an operating point for voice and data transmission via the analogous subscriber line. The first and the second capacitor block equisignals on the subscriber line so that no direct current can flow via the analogous subscriber line.

Abstract: A method and a device for amplifying a reception signal are provided, involving the adjustment of a gain by which the reception signal is amplified, in particular as a function of a signal level of the reception signal. For example, lowpass filtering with a variable cutoff frequency is used to filter out a gain-dependent frequency range of the reception signal, which may especially contain an undesirable echo signal. Such a method and such a device are suitable in particular for the reception of ADSL signals in a central office.

Abstract: A circuit arrangement for signaling in telecommunications networks has a first connection and a second connection for a first and a second conductor, respectively, in a transmission line. The first connection is connected to the first input of a rectifier, and the second connection is connected to the second input of said rectifier. The positive output and the negative output of the rectifier are connected to one another via a variable resistance. A third connection for a third conductor in the transmission line can be connected via the series circuit formed by a switch and a first diode to the positive output of the rectifier, and via the series circuit formed by the switch and a second diode to the negative output of the rectifier.

Abstract: Circuit arrangement for evaluating an information signal and a method for adjusting a circuit arrangement of this type.

Abstract: A protective circuit for limiting a voltage at a pad of an integrated circuit includes a threshold selector connected between the pad and ground. The input voltage to the threshold selector is the pad voltage. The threshold detector includes a first transistor where load path is connected to the pad. The central terminal of the first transistor is maintained at a threshold voltage derived from the pad voltage. A second transistor has its control terminal connected to a second terminal of the load path of the first transistor. The load path of this second transistor is connected between the pad and ground.