A room-temperature semiconductor maser, including a first matching network, a second matching network, a heterojunction-containing transistor, and a resonant network. The output end of the first matching network is connected to the drain of the heterojunction-containing transistor. The input end of the second matching network is connected to the source of the heterojunction-containing transistor. The gate of the heterojunction-containing transistor is connected to the resonant network. The pumped microwaves are fed into the input end of the first matching network.

A resistive mixer includes a LO matching circuit inserted between the gate of an FET and a LO terminal, a bias circuit that is connected to the gate and applies a bias voltage to the gate, an RF matching circuit inserted between the drain of the FET and an RF terminal, and an IF matching circuit inserted between the drain and an IF terminal. The source of the FET is grounded. The impedance of the RF matching circuit seen from the drain of the FET at an IF frequency is open-circuit, and the impedance of the IF matching circuit seen from the drain of the FET at an RF frequency is open-circuit.

A distributed mixer is configured of an artificial transmission line of which an input end is connected to an LO terminal and a terminal end is connected to an IF terminal, an artificial transmission line of which an input end is connected to an RF terminal, FETs that perform frequency synthesis of LO signals and RF signals and that are disposed following the artificial transmission lines and of which gates are connected to the artificial transmission line and sources are grounded, a bias circuit that applies gate bias voltage to a terminal end of the artificial transmission line, a terminating resistor that connects the terminal end of the artificial transmission line and a ground, and a plurality of transmission lines provided between the artificial transmission line and a drain of each FET.

The invention relates to a mixer circuit, which includes a transconductance stage circuit, a switch stage circuit and a load stage circuit which are electrically connected in sequence. The transconductance stage circuit is used to access a radio frequency voltage signal and convert the radio frequency voltage signal into a radio frequency current signal The switch-level circuit is used to access the local oscillator signal and the radio frequency current signal, and the switch-level transistor is turned on by using the local oscillator signal; the load-level circuit is used to convert the intermediate frequency current signal into a voltage signal for output. In the present invention, the transconductance stage circuit adopts a transistor superposition technology structure, which improves the conversion gain of the mixer; at the same time, it uses a source degenerate inductance structure, which further improves the conversion gain and linearity of the circuit.

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.

Examples of receivers and receiver techniques are described herein. An example system may include a carrier source that may provide a wireless carrier signal and a wireless communication device, separate from the carrier source. The wireless communication device may provide a wireless communication signal containing data. A receiver may include an antenna positioned to receive the wireless carrier signal and the wireless communication signal, a two-port mixer coupled to the antenna and configured to mix the wireless carrier signal and the wireless communication signal to provide an intermediate frequency signal, and a demodulator configured to extract, at least in part, the data from the intermediate frequency signal.

An injection locked frequency divider includes: a resonator circuit including first to fourth inductors; and a mixer circuit receiving an input signal with an input frequency. Each of the third and fourth inductors is coupled between a respective one of the first and second inductors and the mixer circuit. The two circuits cooperate to form a tank circuit having a free-running frequency and defining a frequency locking range which is around three times the free-running frequency and within which the input frequency falls. By at least performing mixing with a differential reference signal pair, the mixer circuit generates, based on the input signal, a differential mixed signal pair with a frequency that is one-third the input frequency.

The disclosure relates to technology for an apparatus having a current conveyer comprising a first stage having a first differential input, and a second stage having a second differential input. The first and second stages are configured to operate in a push-pull mode to provide an output signal at a current conveyer output between the first stage and the second stage. The apparatus has a first frequency mixer configured to generate a first mixer signal based on an input signal and an oscillator signal having a first frequency. The first frequency mixer is configured to provide the first mixer signal to the first differential input. The apparatus has a second frequency mixer configured to generate a second mixer signal based on the input signal and a second oscillator signal having the first frequency. The second frequency mixer is configured to provide the second mixer signal to the second differential input.

A wireless receiving device is provided. The wireless receiving device includes a first passive mixer and a common gate amplifier. The first passive mixer receives an oscillation signal. The common gate amplifier is coupled to the first passive mixer, and automatically adjusts the input impedance of the common gate amplifier according to the oscillation frequency of the oscillation signal.

The present invention discloses a mixer bias circuit including a first reference voltage generation circuit, an amplifier, a first transistor array, a first switch array, a second reference voltage generation circuit, a second transistor array, a second switch array, a first resistive component, and a second resistive component. The mixer bias circuit provides multiple bias voltages by dynamically tracking the common mode voltage of a trans-impedance amplifier (TIA) and compensates for imbalance and mismatch effects by asymmetrically trimming the bias voltages to improve the second-order intercept point of a radio frequency (RF) receiver front-end (RXFE).