The present technology relates to a notch filter capable of easily obtaining a desired frequency characteristic.

In an N-path filter unit, any one of a plurality of N capacitors is selected as a signal path through which a signal passes, so that the capacitor serving as the signal path is temporally switched. A plurality of N-path filter units is cascade-connected and a capacitor is inserted to a connection point between the N-path filter units. The present technology may be applied to the notch filter which eliminates a blocker and the like, for example.

Provided is an intermediate-frequency analog-to-digital conversion device, including: a gain attenuation module, a gain amplification module, a filter and an analog-to-digital conversion module. The gain attenuation module is configured to perform attenuation processing on a received intermediate-frequency signal. The gain amplification module is connected to the gain attenuation module, and configured to perform amplification processing on a signal that is output from the gain attenuation module. The filter is a variable filter, connected to the gain amplification module, and configured to perform filter processing on a signal that is amplified by a gain amplifier. The analog-to-digital conversion module is connected to the filter, and configured to convert a signal that is filtered by the filter into a digital signal. The technical solution solves the technical problem in the related art and achieves the technical effect of improving the universality of the intermediate-frequency analog-to-digital conversion device.

Methods and devices for radio frequency (RF) loopback for transceivers are described. A transceiver for communicating RF signals with a target device may transmit signals at a transmit frequency and receive signals at a (different) receive frequency. The transceiver may include a waveguide diplexer for separating and combining signals based on frequency. The transceiver may be configured to couple a loopback signal from a common port of the waveguide diplexer; the loopback signal may be based on a transmit signal. The transceiver may include a loopback translator to translate the loopback signal from the transmit frequency to the receive frequency and provide the translated loopback signal to a receiver used for receiving signals from the target device. The receiver may compare the translated loopback signal with a representation of the transmit signal to generate a compensation signal. A transmitter may use the compensation signal to adjust subsequent transmit signals.

Methods and devices for radio frequency (RF) loopback for transceivers are described. A transceiver for communicating RF signals with a target device may transmit signals at a transmit frequency and receive signals at a (different) receive frequency. The transceiver may include a waveguide diplexer for separating and combining signals based on frequency. The transceiver may be configured to couple a loopback signal from a common port of the waveguide diplexer; the loopback signal may be based on a transmit signal. The transceiver may include a loopback translator to translate the loopback signal from the transmit frequency to the receive frequency and provide the translated loopback signal to a receiver used for receiving signals from the target device. The receiver may compare the translated loopback signal with a representation of the transmit signal to generate a compensation signal. A transmitter may use the compensation signal to adjust subsequent transmit signals.

A variable filter circuit includes a serial arm connected between ports (P1-P2), a parallel arm having a resonator connected in series between ports (P1-P3), and another parallel arm having another resonator connected in series between ports (P2-P3). The serial arm includes a capacitor connected between the ports (P1-P2), and the parallel arms include variable capacitances connected in series to the resonators.

An example system comprises a first antenna and a modem. The first antenna is configured to receive a signal from a transmitting radio frequency unit. The signal includes data and a known sequence. The modem is configured to retrieve the known sequence from the signal, transform the known sequence and the data into a frequency domain, calculate averages of groups of neighboring frequency points in the frequency domain to reduce the effect of nonlinear noise in the signal, the neighboring frequency points corresponding to the preamble in the frequency domain, compare the calculated averages to an expected frequency response in the frequency domain, determine a correction filter to apply to the data based on the comparison, apply the correction filter on the data in the frequency domain to create corrected data, transform the corrected data from the frequency domain to the time domain, and provide the data.

An electronic device may include wireless circuitry having one or more radios and one or more antennas. The wireless circuitry may operate in the presence of radio-frequency interference coming from various sources, which can cause a loss of sensitivity or desensitization of the wireless circuitry. To detect and mitigate desensitization of the wireless circuitry, one or more processors may receive wireless circuitry performance metric data, discriminate between wideband interference and narrowband interference based on the wireless circuitry performance metric data, and use different representative noise floor values for wideband interference or narrowband interference to characterize the desensitization of the wireless circuitry.

An electronic device may include wireless circuitry having one or more radios and one or more antennas. The wireless circuitry may operate in the presence of radio-frequency interference coming from various sources, which can cause a loss of sensitivity or desensitization of the wireless circuitry. To detect and mitigate desensitization of the wireless circuitry, one or more processors may receive wireless circuitry performance metric data, discriminate between wideband interference and narrowband interference based on the wireless circuitry performance metric data, and use different representative noise floor values for wideband interference or narrowband interference to characterize the desensitization of the wireless circuitry.

A broadband transceiver includes an input to receive an RF signal, an output to output an RF transmit signal, a receiver section coupled to the input, and a transmitter section coupled to the output. A processor coupled to the receiver section and the transmitter section determines and generates an inverse waveform that will result in attenuation of undesired portions of a received RF signal when summed with the received signal, including optionally at one or more of an RF stage and an IF stage. A summing junction coupled between the processor and receiver section sums the inverse waveform with the received signal.

Various embodiments relate to an end of packet (EOP) circuit, including: a reset pulse generator circuit configured to generate a reset pulse when a input signal transitions to a new value; an analog counter circuit configured to receive a squelch signal to start the counter and to receive the reset pulse to reset the counter; and an EOP detector circuit configured to produce a signal indicative that the input signal is an EOP signal based upon an output of the analog counter circuit.