A method of controlling a signal power of a received signal received by a wireless communication device, the method including: measuring the signal power of the received signal at a plurality of time points in response to a gain control signal; calculating a variance of the signal power of the received signal at at least some time points of the plurality of time points; and controlling the signal power of the received signal based on a gain level determined according to the variance of the signal power of the received signal.

A gain adjustment circuit is coupled with a transmitting device and a receiving device that are in proximity to each other. The gain adjustment circuit receives a baseband signal that is generated based on gain signals and a power associated with a reception of a data packet by the receiving device. The gain adjustment circuit further receives previous transmission information of the transmitting device. The gain adjustment circuit predicts a time of transmission of a control packet from the transmitting device and determines whether the time of transmission overlaps with a time period of reception of the data packet by the receiving device. The gain adjustment circuit further generates and provides gain signals to the receiving device such that a signal interference during the transmission of the control packet and the reception of the data packet is mitigated.

Techniques are provided for automatic gain control processing to reduce adverse effects associated with clipped samples resulting from conversion of analog signals to digital signals. A methodology according to an embodiment includes identifying a clipped sample of the digital signal, for example by comparison of the digitized sample values to a threshold value associated with a full scale value of the converter. The method also includes applying a window function to portions of the digital signal. The window function is configured to attenuate samples of the digital signal within a region centered on the identified clipped sample. A Hilbert finite impulse response (FIR) filter may be applied to the digital signal prior to applying the window function. Parameters of the window function are selected based on frequency response characteristics of the FIR filter and on signal to noise ratio requirements of an application that receives the windowed digital signal.

Techniques are provided for automatic gain control processing to reduce adverse effects associated with clipped samples resulting from conversion of analog signals to digital signals. A methodology according to an embodiment includes identifying a clipped sample of the digital signal, for example by comparison of the digitized sample values to a threshold value associated with a full scale value of the converter. The method also includes applying a window function to portions of the digital signal. The window function is configured to attenuate samples of the digital signal within a region centered on the identified clipped sample. A Hilbert finite impulse response (FIR) filter may be applied to the digital signal prior to applying the window function. Parameters of the window function are selected based on frequency response characteristics of the FIR filter and on signal to noise ratio requirements of an application that receives the windowed digital signal.

A gain adjustment circuit is coupled with a transmitting device and a receiving device that are in proximity to each other. The gain adjustment circuit receives a baseband signal that is generated based on gain signals and a power associated with a reception of a data packet by the receiving device. The gain adjustment circuit further receives previous transmission information of the transmitting device. The gain adjustment circuit predicts a time of transmission of a control packet from the transmitting device and determines whether the time of transmission overlaps with a time period of reception of the data packet by the receiving device. The gain adjustment circuit further generates and provides gain signals to the receiving device such that a signal interference during the transmission of the control packet and the reception of the data packet is mitigated.

A device includes a variable gain amplifier, a voltage shifter, a variable gain amplifier half replica module, and an analog to digital converter. The variable gain amplifier includes an input terminal to receive an input signal, an output terminal to provide a first output signal that is biased based on a first common-mode voltage reference. The voltage shifter circuit includes first and second input terminals, and an output terminal to provide, to the analog to digital converter, a third output signal that is biased based on a second common-mode voltage reference. The variable gain amplifier half replica module includes an output terminal coupled to the second input terminal of the voltage shifter circuit, the variable gain amplifier half replica module to control the third output signal of the voltage shifter circuit based on the first common-mode voltage reference and the second common-mode voltage reference.

A radio frequency receiver and an automatic gain control method of the radio frequency receiver is presented. The radio frequency receiver includes an automatic gain control apparatus, a radio frequency component, and an analog to digital converter, where the automatic gain control apparatus further includes: an intensity calculator configured to calculate a relationship between an intensity representation parameter of digital data and a preset intensity threshold within a preset calculation time; and an automatic gain controller configured to compare the relationship calculated by the intensity calculator with a preset relationship threshold, and adjust a gain of the radio frequency component on radio frequency data according to a comparison result, so that an amplitude of the radio frequency data obtained after the gain adjustment is within a receiving range of the analog to digital converter.

An aspect includes a filtering method including operating a first filter to filter a first input signal to generate a first output signal; operating a second filter to filter a second input signal to generate a second output signal; and merging at least a portion of the second filter with the first filter to filter a third input signal to generate a third output signal. Another aspect includes a filtering method including operating switching devices to configure a filter with a first set of pole(s); filtering a first input signal to generate a first output signal with the filter configured with the first set of pole(s); operating the switching devices to configure the filter with a second set of poles; and filtering a second input signal to generate a second output signal with the filter configured with the second set of poles.

An interrogation device, for locating a wireless device, includes a receiver and digital processing circuitry. The receiver includes one or more receiver stages having adjustable gains, and is configured to receive from the wireless device a signal that carries a packet including a direction-finding field, wherein, during reception of the direction-finding field, multiple different temporal sections of the received signal traverse different wireless channels due to switching among different antennas in the interrogation device or in the wireless device and thus have multiple different received-signal levels. The digital processing circuitry is configured, based on the multiple received temporal sections of the signal during reception of the direction-finding field, to (i) adapt the adjustable gains of the receiver stages and (ii) estimate a position of the wireless device.

A circuit for generating a radio frequency signal is provided. The circuit includes an amplifier configured to generate a radio frequency signal based on a baseband signal. Further, the circuit includes a power supply configured to generate a variable supply voltage based on a control signal indicating a desired supply voltage, and to supply the variable supply voltage to the amplifier. The circuit further includes an envelope tracking circuit configured to generate the control signal based on a bandwidth of the baseband signal, and to supply the control signal to the power supply.