Methods, systems, and apparatus, including computer programs encoded on computer storage media, for a radio frequency (RF) receiver including a dual-mode low noise amplifier (LNA). One of the methods includes configuring the RF receiver to a wideband mode including operation over a multiple receive frequency (RX) bands including multiple frequencies, receiving, by the RF receiver, an input RF signal, scanning the multiple frequencies to detect a transmitted frequency of the input RF signal, configuring the RF receiver to narrowband mode including operation over a proper subset of the RX bands including a proper subset of the multiple frequencies, and tuning the RF receiver to the transmitted frequency.

An apparatus includes a radio-frequency (RF) receiver for receiving RF signals. The RF receiver includes a plurality of modulation signal detectors (MSDs) to generate a plurality of detection signals when a plurality of RF signals modulated using a plurality of modulation schemes are detected. The RF receiver further includes a controller to cause reception of the plurality of RF signals in response to the plurality of detection signals.

An electronic device may include wireless circuitry with a baseband processor, a transceiver, and an antenna. The transceiver may include a mixer that outputs signals to a transimpedance amplifier. The mixer has an output impedance that varies depending on the frequency of operation. An adjustable resistance can be coupled to the input of the transimpedance amplifier. A control circuit can tune the adjustable resistance to compensate for changes in the output impedance of the mixer as the transceiver operates across a wide range of frequencies.

Provided is an oscillator circuit including an LC oscillator circuit, an amplitude detection circuit, and a bias generation circuit, in which the LC oscillator circuit includes an inductor and at least one variable capacitance element, the amplitude detection circuit detects an oscillation amplitude of the LC oscillator circuit and converts the oscillation amplitude into a DC voltage, and the bias generation circuit compares the DC voltage with a voltage for generating a bias signal, the voltage changing on the basis of a temperature fluctuation of the bias generation circuit, calculates a difference between the DC voltage and a voltage after the change, and generates, on the basis of the difference, a bias signal that reduces a fluctuation in the oscillation amplitude, to control the oscillation amplitude.

An integrated circuit and a method of performing a built-in-self-test (BIST) procedure in an integrated circuit. The integrated circuit includes a plurality of radio circuits and a switching network for performing a built-in-self-test (BIST) procedure. The switching network includes a plurality of combiners, a plurality of transmitter connection switches, a combiner switch, a splitter switch, a plurality of splitters and a plurality of receiver connection switches. The switching network may also include a splitter bypass switch and/or a combiner bypass switch. The components of the switching network may operate to route signals between outputs and inputs of the radio circuit to implement the built-in-self-test procedure in one or more modes involving either parallel or sequential testing of the components of the radio circuits. A diagnostic mode is also envisaged.

A signal analysis device includes: a plurality of time-frequency conversion units that are each provided corresponding to one of a plurality of sampling sequences and convert a corresponding sampling sequence, the plurality of sampling sequences having been subjected to sampling performed at a sampling rate lower than a Nyquist rate from a plurality of signal systems generated by branching a signal of interest, and having received addition of delay times different from each other; signal processing units that collectively perform a phase compensation process corresponding to a sub-Nyquist zone of the sampling sequence output by a corresponding time-frequency conversion unit and a process of canceling phase rotation caused by a delay time difference between the plurality of sampling sequences; and a frequency estimation unit that estimates a frequency of the signal of interest by determining from which sub-Nyquist zone the signal of interest has been folded.

A wireless device including a receiver circuit coupled to a radio frequency receiver node, a frequency selective attenuator including an inductor and a first capacitor coupled in series to the radio frequency receiver node, and a second capacitor coupled in parallel with the first capacitor. The first capacitor has a first capacitance based on a blocker frequency and the second capacitor has a second capacitance that linearizes the frequency selective attenuator. A method of linearizing a frequency selective attenuator including detecting presence of a blocker signal, activating and programming a capacitor of the frequency selective attenuator to reduce a strength of the blocker signal, determining a frequency difference between the blocker signal and a receive frequency, and coupling a second capacitor to the frequency selective attenuator to linearize the frequency selective attenuator when the frequency difference is no more than an attenuation threshold.

Various data transmission detection systems are described. A receiver input through which a wireless data transmission signal is received may be present. A plurality of mixers in communication with the receiver input may be present, which may be digitally implemented. A data transmission detector may be present that receives a mixed wireless data transmission signal from each mixer and creates a plurality of scores. A match detection module may be present that receives the scores and identifies a highest score. The signal mapped to the highest score to be selected for further processing.

Radio frequency front end modules implementing coexisting time division duplexing and frequency division duplexing are provided. In one aspect, a front end system includes a time-division duplexing transmit terminal, a time-division duplexing receive terminal, a frequency division duplexing terminal, and an antenna terminal. The front end system further includes first, second, and third switches configured to selectively connect the terminals to either a node or the antenna. The front end system also includes a controller configured to provide delays between disconnecting the terminals from the antenna and connecting the terminals to the node.

The present invention relates to the acquisition, processing, and monitoring of signals, and particularly to the acquisition, processing, and monitoring of electrophysiological signals. More particularly, the present invention relates to the acquisition, processing, and monitoring electroencephalography (EEG) signals representing cortical/brain activity. Further, the present invention relates to a method and apparatus for acquiring such signals in the presence of electrical interference and noise. More particularly, the present invention relates to systems and methods for filtering out and rejecting electrical interference and noise while maintaining or improving the quality of the underlying physiological signal and preventing perturbation or introduction of artifacts into the physiological signal.