Realtek Semiconductor Inc.

Yi-Chang Shih

Yi-Shao Chang

Ka-Un Chan

Yi-Cheng Chen

Chia-Chun Hung

Yi-Lin Li

Hou-Wei Lin

Yu-Che Yang

Liang-Hui Li

Wei-Cheng Lin

Yuan-Shuo Chang

Chih-Wei Lai

Kun-Hsun Liao

Yu-Jung Li

Ying-His Lin

Ching-Her Huang

A signal receiving circuit receives an input signal and includes a radio frequency (RF) front-end circuit, a filter circuit, an amplifier circuit, an analog-to-digital converter (ADC), a compensation circuit, an adder circuit, and a control circuit. The RF front-end circuit down-converts the input signal to generate a down-converted signal. The filter circuit filters the down-converted signal to generate a filtered signal. The amplifier circuit amplifies, according to a control signal, the filtered signal with a gain to generate an amplified signal. The ADC converts the amplified signal into a first digital code. The compensation circuit generates a compensation code according to at least one of the control signal and the gain. The adder circuit generates a second digital code according to the compensation code and the first digital code. The control circuit generates the control signal according to the second digital code.

Signal receiving circuit and calibration method thereof

The present invention provides a transceiver circuit including a transmitter circuit, a frequency synthesizer and control circuit. The transmitter circuit is configured to generate a transmission signal, wherein the transmission signal is transmitted through an antenna. The frequency synthesizer is configured to generate a clock signal for the transmitter circuit to generate the transmission signal. The control circuit is configured to generate a first control signal to control the frequency synthesizer to determine a loop bandwidth of the frequency synthesizer; wherein when the transceiver circuit operates in a standby mode, the control circuit generates the first control signal to make the frequency synthesizer have a first loop bandwidth; and after a period of time after the transceiver circuit is switched from the standby mode to a transmission mode, the control circuit generates the first control signal to make the frequency synthesizer have a second loop bandwidth.

Transceiver circuit and control method of frequency synthesizer

A transceiver circuit includes a transceiver antenna, a transmitter circuit, a receiver circuit, a frequency synthesizer and a baseband circuit. The transmitter circuit transmits a radio frequency signal corresponding to a radio frequency through the transceiver antenna. The frequency synthesizer provides a first local oscillation signal and a second local oscillation signal having a first local oscillation frequency and a second local oscillation frequency, respectively. The baseband circuit operates in a transmitting mode and a receiving mode. In the transmitting mode, the frequency synthesizer provides the first local oscillation signal, and in the receiving mode, the frequency synthesizer provides the second local oscillation signal, the first local oscillation frequency is a non-integer multiple of the radio frequency, and the second local oscillation frequency is an integer multiple of the radio frequency.

Transceiver circuit

An apparatus for use in a polar transmitter to perform distortion estimation and compensation is provided. The apparatus includes a mixing unit, a signal processing unit, an estimation unit and a compensation unit. The mixing unit is configured to mix a test output signal and a frequency down-converting signal to generate a mixed signal. The processing unit is configured to perform signal processing on the mixed signal to generate a processed signal. The estimation unit is configured to perform distortion estimation on the processed signal to generate a distortion estimation result. The compensation unit is configured to perform pre-distortion compensation on input signals of the polar transmitter according to the distortion estimation result.

Method and apparatus for use in polar transmitter to perform nonlinear distortion estimation and compensation

A wireless device includes a radio-frequency module, a modem module, and a control unit. The radio-frequency module and the modem module operate either in a first operation mode or in a second operation mode. The control unit, coupled to the RF and the modem module, generates a control signal to indicate to the RF and the modem module to operate in the first operation mode or to operate in the second operation mode. A first set of signal formats corresponding to the first operation mode is a superset of a second set of signal formats corresponding to the second operation mode, and a first power consumption corresponding to the first operation mode is higher than a second power consumption corresponding to the second operation mode.

Radio-frequency module and wireless device

A method of receiving an RF signal is applied to a receiving circuit of a wireless communication system and amplifies the RF signals according to an analog gain. The RF signal includes data signals and interference signals. The method includes steps of: employing a low noise amplifier (LNA) to amplify the RF signal according to a first gain to generate an amplified RF signal, the first gain being associated with a first bias signal; detecting the amplified RF signal in an RF band to generate a control signal corresponding to the power of the amplified RF signal, the control signal being an analog signal; providing the first bias signal to the LNA according to the control signal; down-converting the amplified RF signal to generate an intermediate frequency or baseband signal; and filtering the intermediate frequency or baseband signal to filter out the interference signal and thus obtain the data signal.

Receiving circuit of wireless communication system and method of receiving RF signal

A dual-mode signal transceiver includes a first transmitter circuit, a second transmitter circuit, and a receiver circuit. The first transmitter circuit is configured to operate in a first mode and configured to process a first input signal according to a first oscillating signal, in order to output a first output signal. The second transmitter circuit is configured to operate in a second mode and configured to process a second input signal according to a second oscillating signal, in order to output a second output signal, wherein a frequency of the second oscillating signal is not an integral multiple of a frequency of the first oscillating signal. The receiver circuit is configured to process an external signal associated with one of the first mode and the second mode according to the first oscillating signal, in order to read data associated with the external signal.

Dual-mode signal transceiver and transceiving method thereof

A power supplying circuit for generating an output voltage, which comprises: a noise detecting circuit, for receiving a first reference voltage and for generating a second reference voltage according to the output voltage and the first reference voltage, wherein a noise component of the second reference voltage is the same as which of the output voltage; a control voltage generating unit, for receiving a feedback voltage and the second reference voltage, and for generating a control voltage according to the feedback voltage and the second reference voltage; a voltage providing device, for generating the output voltage according to the control voltage and an input voltage; and a feedback module, for generating the feedback voltage according to the output voltage.

Power supplying circuit and power supplying method

The present invention relates to a receiving apparatus of a communication system, which comprises a receiving module, a selection unit, and a processing module. The receiving module receives an input signal and produces a first signal and a second signal. The phases of the first and the second signals are different. The selection unit receives the first and the second signals, and switches for outputting the first or the second signal. The processing module receives and processes the first and the second signals, and produces an output signal. Thereby, the present invention uses the selection unit for processing two phase signals via a set of channels. Thereby, circuit area and power consumption can be reduced, and hence achieving the purpose of saving cost.

Receiving apparatus with a single set of channels for processing plural sets of in-phase and quadrature phase signals

A communication device is disclosed, having a wireless LAN transceiver, a wireless LAN demodulation circuit, a Bluetooth transceiver, a Bluetooth demodulation circuit, an oscillator, and a mixer. The wireless LAN transceiver conducts communication in a first frequency band and the wireless LAN demodulation circuit demodulates the wireless LAN signals. The Bluetooth transceiver conducts communication in a second band and a third frequency band, which are higher and lower than the first frequency band, respectively. The oscillator generates oscillating signals. The mixer mixes the signals in the second frequency band with an oscillating signal, which is higher than the second frequency band, and mixes the signals in the third frequency band with another oscillating signal, which is lower than the third frequency band to generate mixed signals. The Bluetooth demodulation circuit demodulates the mixed signals of the mixer.

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Hsinchu, Taiwan

Yi-Chang Shih