A cascadable AGC amplifier in a signal distribution system includes a low noise cascadable amplifier having a through path and a cascadable output. The cascadable amplifier is also configured to provide AGC over a predetermined input power range. The cascadable AGC amplifier can be configured to provide gain or attenuation. When the cascadable AGC amplifier is implemented in a signal distribution system, typically as part of a signal distribution device, an input signal can be gain controlled and supplied to multiple signal paths without distortion due to degradation of signal to noise ratio or distortion due to higher order amplifier products. The distributed signal is not significantly degraded by distortion regardless of the number of cascadable AGC amplifiers connected in series or the position of the cascadable AGC amplifier in the signal distribution system.

A configurable passive mixer is described herein. According to one exemplary embodiment, the passive mixer comprises a clock generator, a controller, and a plurality of passive mixer cores connected in parallel. The clock generator comprises a local oscillator drive unit for each passive mixer core. The controller varies an effective transistor size of the passive mixer by separately configuring each of the passive mixer cores to enable/disable each passive mixer core. For example, the controller may selectively enable one or more of the passive mixer cores to vary the effective transistor width of the passive mixer. As the performance requirements and/or the operating communication standard change, the controller may re-configure each passive mixer core.

A processor may calibrate a first actuator electrically coupled to a transconductance stage of the frequency conversion circuit. The transconductance stage may be configured to receive a differential signal input. Calibrating a first actuator may adjust a first basis vector associated with a differential direct current (DC) output of the transconductance stage. A processor may calibrate a second actuator electrically coupled to receive the differential current output of the transconductance stage and electrically coupled to a set of commutating devices of the frequency conversion circuit. The commutating devices may be configured to receive differential LO inputs. Calibrating a second actuator may adjust a second basis vector associated with a differential impedance of the set of commutating devices. A processor may offset responsive to adjusting the first basis vector and the second basis vector, the first leakage basis vector and second leakage basis vector of the LO leakage signal.

In one example, a circuit includes a first node to receive an analog signal that is an amplitude modulated radio-frequency signal for a digital signal. An output node is configured to provide an output signal indicative of rising and falling edges of an envelope of the analog signal. The rising and falling edges are indicative of rising and falling edges of the digital signal. A first current path is disposed between a power supply node and the first node. The first current path includes a first transistor coupled between the first node and a first bias source. The first bias source is coupled between the first transistor and the power supply node. The output node is coupled to a first intermediate node in the first current path between the transistor and the first bias source. A control terminal of the first transistor is coupled to the output node via a feedback network.

A source injection mixer includes an FET, an IF matching circuit between an IF port and a gate of the FET, and that matches impedance of the IF port and impedance of the gate as viewed from the IF port, a shorting stub of which one end is connected to a source of the FET and another end is grounded, and shorter than ¼ of an electric length at a frequency of LO signals, an LO matching circuit between an LO port and the source of the FET, and that matches impedance of the LO port and impedance of the source as viewed from the LO port, and an RF matching circuit between an RF port and a drain of the FET, and that matches impedance of the RF port and impedance of the drain as viewed from the RF port.

The invention discloses a power mixer, radio frequency circuit, device and equipment, and belongs to the technical field of electronics and communication. The power mixer includes a mixer module, which amplifies an analog baseband current signal by a silicon germanium heterojunction bipolar transistor amplifying circuit, and converts a local oscillator voltage signal into a local oscillator current signal by a silicon germanium heterojunction bipolar transistor switching circuit. The silicon germanium heterojunction bipolar transistor switching circuit receives an amplified analog baseband current signal, and mixes the amplified analog baseband current signal and the local oscillator current signal into a radio frequency current signal; and a transformer module, which converts the radio frequency current signal into a radio frequency power signal and then outputs the radio frequency power signal from the power mixer.

Provided is a FET resistive frequency mixing device having improved RF-LO and IF-LO isolations. The frequency mixing device includes: a field effect transistor (FET), a local oscillation matching circuit connected to a gate of the FET to transfer a local oscillation signal to the gate of the FET, a gate biasing circuit connected to the gate of the FET, a radio frequency (RF) matching circuit having a first terminal connected to a drain side of the FET and a second terminal serving as a RF terminal to receive or output a RF signal, an intermediate frequency (IF) matching circuit having a first terminal connected to the drain side of the FET and a second terminal serving as an IF terminal to receive or output an IF signal, and a series resonance circuit providing a path from the drain of the FET to ground for the local oscillation signal.

A configurable passive mixer is described herein. According to one exemplary embodiment, a passive mixer for a wireless receiver comprises a plurality of passive mixer cores coupled in parallel with each mixer core configured to receive a same set of radio frequency input signals and a separately driven set of local oscillator input signals. Further, each mixer core is configured to be separately enabled or disabled so that the passive mixer can be selectively configured during operation to convert the same set of radio frequency input signals to a set of downconverted output signals that satisfy a certain performance requirement or performance parameter of the passive mixer.

A transmitter that reduces 3.sup.rd order harmonic (HD3) and inter modulation distortion (IMD3) for a gm stage of a mixer while reducing flicker noise is disclosed. The transmitter may include a balanced mixer, a transconductance stage connected to the mixer, and a bias circuit. The bias circuit may include a programmable current source configured to provide a reference current. Further, the bias circuit may include a replica circuit configured to replicate a DC signal of the transconductance stage. The bias circuit may also include a bias transistor configured to level shift a bias signal obtained from a signal source based on the reference current and the DC signal of the transconductance stage as determined from the replica circuit.

Provided is a FET resistive frequency mixing device having improved RF-LO and IF-LO isolations. The frequency mixing device includes: a field effect transistor (FET), a local oscillation matching circuit connected to a gate of the FET to transfer a local oscillation signal to the gate of the FET, a gate biasing circuit connected to the gate of the FET, a radio frequency (RF) matching circuit having a first terminal connected to a drain side of the FET and a second terminal serving as a RF terminal to receive or output a RF signal, an intermediate frequency (IF) matching circuit having a first terminal connected to the drain side of the FET and a second terminal serving as an IF terminal to receive or output an IF signal, and a series resonance circuit providing a path from the drain of the FET to ground for the local oscillation signal.