55results about "Modulation transference by semiconductor devices with minimum 2 electrodes" patented technology

The invention discloses a wireless direction finder circuit and a wireless direction finder, and relates to the technical field of wireless direction finding. Wherein the wireless direction finder circuit comprises a local oscillation signal input end, a frequency mixing detection circuit, a rectifying circuit, a main control circuit and an inflexion output circuit. The frequency mixing detection circuit generates a frequency mixing signal according to the wireless signal and the local oscillator signal. The rectifying circuit converts the frequency mixing signal into a first direct current signal. And the main control circuit outputs an inflexion control signal when the voltage value of the first direct current signal is greater than or equal to a preset voltage value. When the inflexion output circuit does not receive the inflexion control signal, the inflexion output circuit outputs a corresponding first audio signal according to the frequency mixing signal; and when the inflexion control signal is received, the second audio signal of frequency conversion is output according to the inflexion control signal and the frequency mixing signal, so that a user can be prompted that the signal intensity is relatively high at the moment and the signal source has entered the preset distance range. According to the invention, positioning is assisted through a dual change mechanism of tone and volume, so that positioning efficiency and environmental adaptability are improved.

Circuitry is provided that includes a matching circuit, a first mixer coupled to the matching circuit and configured to receive a signal with an oscillation frequency, a second mixer coupled to the matching circuit, a first transmission line path coupled between the matching circuit and an input of the first mixer, and one or more capacitors coupled to the input of the first mixer and configured to reject signals at a harmonic frequency of the oscillation frequency. The wireless circuitry can further include a second transmission line path coupled between the matching circuit and an input of the second mixer. The transmission line path can include a first transmission line for conveying signals between the matching circuit and the first mixer, a second transmission line for conveying signals between the matching circuit and the first mixer, and a floating transmission line interposed between the first and second transmission lines.

Mixer circuitry can include a first pair of transistors coupled to a first tail node and configured to receive a local oscillator signal, a second pair of transistors coupled to a second tail node and configured to receive the local oscillator signal, a first digital-to-analog converter, a second DAC coupled between the first DAC and of the first pair of transistors, and a third DAC coupled between the first DAC and the second pair of transistors. During a first phase, control circuitry can sweep the first DAC to trim a first and / or other odd order local oscillator feedthrough. During a second phase, the control circuitry can sweep the second DAC to trim a second and / or other even order local oscillator feedthrough. During a third phase, the control circuitry can sweep the second and third DACs to reject signals associated with a second harmonic conversion gain of the mixer circuitry.

Mixer circuitry can include a first pair of transistors coupled to a first tail node and configured to receive a local oscillator signal, a second pair of transistors coupled to a second tail node and configured to receive the local oscillator signal, a first digital-to-analog converter, a second DAC coupled between the first DAC and of the first pair of transistors, and a third DAC coupled between the first DAC and the second pair of transistors. During a first phase, control circuitry can sweep the first DAC to trim a first and / or other odd order local oscillator feedthrough. During a second phase, the control circuitry can sweep the second DAC to trim a second and / or other even order local oscillator feedthrough. During a third phase, the control circuitry can sweep the second and third DACs to reject signals associated with a second harmonic conversion gain of the mixer circuitry.

In one example, an RF oscillator system includes a laser source configured to emit laser light, a housing, a crystalline microresonator disposed within the housing, and a photonic integrated circuit disposed within the housing, the photonic integrated circuit including an optical waveguide network and configured to generate a clock signal based on the laser light. The RF oscillator system may further include at least one photonic wirebond configured to couple the laser light between the optical waveguide network and the crystalline microresonator via evanescent coupling; laser control circuitry disposed within the housing and configured to lock a frequency of the laser light to a resonance of the microresonator to generate the clock signal; and a direct digital synthesizer disposed within the housing and configured to produce a tunable oscillator signal based on the clock signal.

Certain aspects provide a circuit for frequency translation. The circuit includes first mixer circuitry coupled to a load circuit and having a first mixer configured to generate, based on a first differential input signal and a second differential input signal, a first portion of a frequency translated differential signal to be provided to the load circuit, and a second mixer configured to generate, based on a third differential input signal and a fourth differential input signal, a second portion of the frequency translated differential signal. The circuit also includes second mixer circuitry coupled to another load circuit and having a third mixer configured to generate, based on the first differential input signal and the fourth differential input signal, a first portion of another frequency translated differential signal, and a fourth mixer configured to generate, based on the third differential input signal and the second differential input signal, a second portion of the another frequency translated differential signal.

A passive mixer circuit includes a high-frequency terminal, a low-frequency terminal, a main MOSFET to which a local oscillation frequency signal is input, and a bias generation section, in which the bias generation section includes a sub-MOSFET of a same type as the main MOSFET, a voltage follower circuit including an operational amplifier, and a resistance element, a drain and a gate of the sub-MOSFET are shorted and directly or indirectly receive an output from the voltage follower circuit, a reference voltage is input to a non-inverting input terminal of the operational amplifier, a gate bias voltage based on a gate voltage of the sub-MOSFET is supplied to a gate of the main MOSFET, and a source-drain bias voltage based on a source voltage of the sub-MOSFET is supplied to a source or a drain of the main MOSFET.

Circuitry (24) is provided that includes a matching circuit (100), a first mixer (50-1) coupled to the matching circuit and configured to receive a signal with an oscillation frequency, a second mixer (50-2) coupled to the matching circuit, a first transmission line path (102-1) coupled between the matching circuit (100) and an input of the first mixer (50-1), and one or more capacitors (104) coupled to the input of the first mixer (50-1) and configured to reject signals at a harmonic frequency of the oscillation frequency. The wireless circuitry (24) can further include a second transmission line path (102-2) coupled between the matching circuit (100) and an input of the second mixer (50-2). The transmission line path can include a first transmission line for conveying signals between the matching circuit (100) and the first mixer (50-1), a second transmission line for conveying signals between the matching circuit (100) and the first mixer (50-1), and a floating transmission line interposed between the first and second transmission lines.

Methods and apparatus for calibration of a second-order input intercept point (IIP2) of a mixer, such as a mixer in a wireless receive chain. One example circuit for mixer IIP2 calibration generally includes a first receive chain comprising a first mixer and a single tone generator having an output coupled to an input of the first mixer and configured to generate a calibration signal having a single baseband tone. One example method of mixer IIP2 calibration generally includes generating a calibration signal comprising a single baseband tone, applying the calibration signal to an input of a mixer, such that the mixer generates a differential tone at an output of the mixer, and adjusting the mixer to minimize a power of the differential tone at the output of the mixer.

A receiver circuit comprises a local oscillator (LO) signal generator that provides LO reference voltage signals, and a plurality of up-conversion paths that provide filtered up-converted signals. Each up-conversion path comprises a transistor and a bandpass filter. A drain of the transistor provides a mixed signal in response to one of the LO reference voltage signals at a gate of the transistor and an RF input signal at a source of the transistor. The bandpass filter has a fixed frequency that passes a first frequency component associated with a center frequency of the RF input signal and rejects a second frequency component associated with an undesired frequency in the mixed signal to provide one of the filtered up-converted signals. The fixed bandpass frequency may reject a plurality of second frequency components that are associated with a plurality of undesired frequencies of the RF input signal.

In certain aspects, an apparatus includes a transformer including an input inductor and an output inductor, wherein the input inductor is magnetically coupled to the output inductor. The apparatus also includes a transconductance driver configured to drive the input inductor based on an input signal. The apparatus further includes a feedback circuit configured to detect an output voltage swing at the output inductor, generate a regulated voltage at the input inductor, and control the regulated voltage based on the detected output voltage swing.

A radio-frequency modulator apparatus comprises a baseband stage, a mixer stage and a radio-frequency stage. The baseband stage comprises: an input line for receiving an input current representative of a baseband input signal, a baseband transistor that passes some or all of the input current between a first and a second terminal thereof, an electrical connection between the input line and a control terminal of the baseband transistor, and an output line connected to said control terminal. The mixer stage receives a signal from the baseband stage and mixes it with a radio-frequency local-oscillator signal to generate a radio-frequency mixed signal. The radio-frequency stage receives the radio-frequency mixed signal, applies the radio-frequency mixed signal to a control terminal of a radio-frequency transistor causing it to pass a radio-frequency output current between a first and a second terminal thereof, and outputs the radio-frequency output current as an output signal.

The mixer-first topology of receivers do not include low-noise amplifiers (LNA) preceding the mixer. The Mixer-First topology of radio receivers utilizes a direct-conversion quadrature mixer to down convert an RF signal to baseband, where a Hilbert Transform filter is used for sideband selection. When a switching mixer is used, the mixer-first receiver is capable of extremely high dynamic range and linearity. The downfall of the mixer-first topology is poor out-of-band signal rejection. A mixer-first receiver is described which achieves third-harmonic rejection without bandpass filtering proceeding the mixer.

Provided is a reception apparatus that includes an in-phase-side mixer that mixes a high-frequency component and an in-phase-side local signal, and outputs the mixed signal as an in-phase-side mixed signal, a quadrature-side mixer that mixes the high-frequency component and a quadrature-side local signal orthogonal to the in-phase-side local signal, and outputs the mixed signal as a quadrature-side mixed signal, an error detection signal generation unit that generates four-phase detection signals having same frequencies as frequencies of the in-phase-side local signal and quadrature-side local signal, and each having a different phase, and a signal processing unit that generates a gain difference between an in-phase-side signal according to the in-phase-side mixed signal and a quadrature-side signal according to the quadrature-side mixed signal, on the basis of respective output signals of the in-phase-side mixer and quadrature-side mixer in a case where each of the four-phase detection signals is the high-frequency component.

The invention discloses a frequency mixer, which is characterized by comprising a first transistor; a second transistor; a third transistor; a first connection point for connecting to a gate terminal of the first transistor, a drain terminal of the second transistor, and a source terminal of the third transistor; a second connection point for connecting to a source terminal of the first transistor and a gate terminal of the second transistor; and a third connection point for connecting to the drain terminal of the first transistor and the drain terminal of the third transistor.

Systems, circuits, and methods for mixing signals are provided. An illustrative circuit may include mixer circuitry including multiple inputs and at least one output, where the multiple inputs are connected across a local oscillator. The circuit may further include a terminal Radio Frequency (RF) output circuitry that is isolated from the local oscillator, where the at least one output of the mixer circuitry is directly connected to an input of the terminal RF output circuitry. The circuit may further include terminal Intermediate Frequency (IF) output circuitry that is isolated from the local oscillator, where the at least one output of the mixer circuitry is directly connected to an input of the terminal IF output circuitry.

A communication system comprising a passive quadrature generator directly connected to an in-phase (I) mixer and a quadrature (Q) mixer; an I-LO amplitude detection circuit connected to the passive quadrature generator and connected to the I-mixer, and a Q-LO amplitude detection circuit connected to the passive quadrature generator and connected to the Q-mixer, the I-LO amplitude detection circuit configured to detect an I-LO amplitude, and the Q-LO amplitude detection circuit configured to detect a Q-LO amplitude; and a combining and integrating circuit configured to receive the detected I-LO amplitude and the detected Q-LO amplitude, and to generate an I-LO DC bias voltage for biasing the I mixer and a Q-LO DC bias voltage for biasing the Q mixer.

Embodiments disclose an apparatus for generating radio frequency signals in phase quadrature. The integrated electronic device includes a mixer module comprising a voltage / current transconductance stage including a first transistor and connected to a mixing stage including a second transistor, wherein the mixing stage includes: a resistance degeneration circuit connected to the source of the second transistor; and a calibration input connected to the gate of the second transistor and intended to receive an adjustable calibration voltage, and the source of the first transistor is directly connected to a cold power supply point.

A system includes a mixer, an amplifier, and a switchable transformer. The switchable transformer includes a primary inductor coupled between a first output and a second output of the mixer, a first switch, a second switch, and a secondary inductor coupled between a first input and a second input of the amplifier, wherein the secondary inductor is magnetically coupled with the primary inductor. The secondary inductor includes a first inductor coupled between the first input of the amplifier and a first terminal of the first switch, a second inductor coupled between a second terminal of the first switch and the second input of the amplifier, a third inductor coupled between the first terminal of the first switch and a first terminal of the second switch, and a fourth inductor coupled between the second terminal of the first switch and a second terminal of the second switch.

In an example, a system includes a receiver configured to receive a differential input signal from a quadrature amplitude modulation (QAM) transmitter at a differential interface that includes a first input and a second input. The system also includes a first switch coupled to the first input and a second switch coupled to the second input, where the first switch and second switch are configured to couple the first input and the second input to a complex mixer in a non-inverting configuration. The system includes a third switch coupled to the first input and a fourth switch coupled to the second input, where the third switch and the fourth switch are configured to couple the first input and the second input to the complex mixer in an inverting configuration. The complex mixer is configured to produce an output signal based on the non-inverting configuration and the inverting configuration.

Disclosed is a radio frequency (RF) circuit including a mixer configured for independent second order intercept point (IP2) calibration. The mixer includes three ports and multiple dual-gate transistors interconnected therebetween for down-converting an RF input signal to a lower frequency baseband output signal. To optimize performance, front gates of the transistors are biased with a front gate bias voltage (Vfg). To adjust second order non-linearity, back gates of the transistors are biased using a first back gate bias voltage (Vbgp) for half of the transistors of the mixer and a second back gate bias voltage (Vbgm) for a different half of the transistors. The circuit can also include a front gate bias voltage generator for generating Vfg and a back gate bias voltage generator (including a digital-to-analog converter (DAC) with multiple DAC units) for generating Vbgp and Vbgm independent of Vfg. Also disclosed is an associated operating method.

A mixer circuit according to the present invention comprises: a mixer (1); an LO matching circuit (6) inserted between an LO signal terminal (5) and a first terminal (2) of the mixer (1); an IF matching circuit (8) inserted between an IF signal terminal (7) and a second terminal (3) of the mixer (1); and an RF matching circuit (10) inserted between an RF signal terminal (9) and a third terminal (4) of the mixer (1). The reflection characteristics for the RF matching circuit (10) are set such that the minimum value of reflection loss appears on the high frequency side of the LO signal frequency.

A method and apparatus are described for bio-impedance measurement using voltage to current conversion. In one example, a bio-impedance transducer includes an input stage to receive a bio-impedance signal having an oscillating voltage from two electrodes, the electrodes being coupled to a body, a resistance across the two electrodes to determine an alternating current of the bio-impedance signal, a gain stage coupled to the resistance to amplify the alternating current, a down converter coupled to the gain stage to convert the amplified alternating current to a direct current bio-impedance signal, and an analog-to-digital converter coupled to the down converter to convert the direct current bio-impedance signal to a digital bio-impedance signal.

The present disclosure provides a circuit for generating a bias voltage for a passive mixer, including: a bias module for providing a bias current; a bias voltage generation module for generating a gate bias voltage required for the PMOS transistor of the subsequent-stage passive mixer and the source-drain common-mode level of the NMOS and PMOS transistors of the subsequent-stage passive mixer under the action of the bias current; and a compensation module for compensating the bias voltage and the source-drain common-mode level, so that the RF input impedance of the subsequent-stage passive mixer during operation does not change with temperature, process, and power supply voltage; wherein, the gate bias voltage required for the NMOS transistor of the subsequent-stage passive mixer is directly provided by the power supply voltage VDD.

A communication system includes a passive quadrature generator connected directly to an in-phase (I) mixer and a quadrature (Q) mixer, an I LO amplitude detect circuit connected to the passive quadrature generator and connected to the I mixer, and a Q LO amplitude detect circuit connected to the passive quadrature generator and connected to the Q mixer, the I LO amplitude detect circuit configured to detect an I LO amplitude and the Q LO amplitude detect circuit configured to detect a Q LO amplitude, and a combining and integrating circuit configured to receive the detected I LO amplitude and the detected Q LO amplitude and generate an I LO DC bias voltage to bias the I mixer and a Q LO DC bias voltage to bias the Q mixer.

The application discloses a wireless direction finder circuit and a wireless direction finder, and relates to the technical field of wireless direction finding. The wireless direction finder circuit comprises a local oscillator signal input end, a mixed frequency detection circuit, a rectifier circuit, a main control circuit and a variable sound output circuit. The mixed frequency detection circuit generates a mixed frequency signal according to a wireless signal and a local oscillator signal. The rectifier circuit converts the mixed frequency signal into a first direct current signal. The main control circuit outputs a variable sound control signal when the voltage value of the first direct current signal is greater than or equal to a preset voltage value. The variable sound output circuit outputs a corresponding first audio signal according to the mixed frequency signal when the variable sound control signal is not received, and outputs a second audio signal of a variable frequency according to the variable sound control signal and the mixed frequency signal when the variable sound control signal is received, so that the user can be prompted that the signal strength is large at the moment and the signal source has entered a preset distance range. The application assists positioning through a dual change mechanism of tone and volume, and improves positioning efficiency and environmental adaptability.

A frequency mixer arrangement (300, 400, 500, 600) for receiving a first input signal (LOin) and a second input signal (IFin; RFin), for mixing the first and the second input signals to provide a frequency mixed signal (RFout; IFout), and for providing the frequency mixed signal as an output signal. The frequency mixer arrangement (300, 400, 500, 600) comprises: a first transistor (210), wherein the first transistor (210) is configured to receive the first and the second input signals at a control terminal (211) of the first transistor (210) and to mix the first and the second input signals to provide the frequency mixed signal from a current-sourcing terminal (213) of the first transistor (210), and wherein the first transistor (210) is configured to receive a first bias voltage (Vb1) at the control terminal (211) of the first transistor (210) and to receive a first supply voltage (Vcc1) at a current-collecting terminal (212) of the first transistor (210); and a diode (250), wherein an anode (251) of the diode (250) is galvanically connected to the current-sourcing terminal (213) of the first transistor (210) and a cathode (252) of the diode (250) is galvanically connected to ground, wherein the frequency mixer arrangement (300, 400, 500, 600) further comprises an inductive component (380) connected in series between the anode (251) of the diode (250) and the current-sourcing terminal (213) of the first transistor (210).

A method and apparatus are described for bio-impedance measurement using voltage to current conversion. In one example, a bio-impedance transducer includes an input stage to receive a bio-impedance signal having an oscillating voltage from two electrodes, the electrodes being coupled to a body, a resistance across the two electrodes to determine an alternating current of the bio-impedance signal, a gain stage coupled to the resistance to amplify the alternating current, a down converter coupled to the gain stage to convert the amplified alternating current to a direct current bio-impedance signal, and an analog-to-digital converter coupled to the down converter to convert the direct current bio-impedance signal to a digital bio-impedance signal.

An apparatus for mixing signals is disclosed. In an exemplary embodiment, the apparatus includes a mixer circuit having a plurality of local oscillator nodes, a first node corresponding to a first frequency, and a plurality of second nodes corresponding to a second frequency. The mixer circuit includes a plurality of capacitors coupled between the plurality of local oscillator nodes and the plurality of second nodes. The mixer circuit has a plurality of switches including a first switch, a second switch, a third switch, and a fourth switch. The plurality of switches are coupled between the plurality of capacitors and the plurality of second nodes. The first switch and the second switch are coupled between the plurality of capacitors and the first node. The first switch and the second switch are disposed between the fourth switch and the third switch.