A novel semiconductor device is provided. The semiconductor device includes a mixer circuit and a bias circuit. The mixer circuit includes a voltage-to-current conversion portion, a current switch portion, and a current-to-voltage conversion portion. The bias circuit includes a bias supply portion and a first transistor. The voltage-to-current conversion portion includes a second transistor and a third transistor. The bias supply portion has a function of outputting a bias voltage to be supplied to a gate of the second transistor and a gate of the third transistor. One of a source and a drain of the first transistor is electrically connected to the gate of the second transistor and the gate of the third transistor. The first transistor is turned off when the bias voltage is supplied, and the first transistor is turned on when the supply of the bias voltage is stopped.

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.

This disclosure describes apparatuses, methods, and techniques for implementing a multimode frequency multiplier. In example implementations, an apparatus for generating a frequency includes a multimode frequency multiplier. The multimode frequency multiplier includes a multiphase generator and a reconfigurable frequency multiplier. The multiphase generator is configured to produce a first signal including multiple phase components and having a first frequency. The reconfigurable frequency multiplier is coupled in series with the multiphase generator. The reconfigurable frequency multiplier is configured to produce a second signal based on the first signal and having a second frequency that is a multiple of the first frequency.

This disclosure describes apparatuses, methods, and techniques for implementing a multimode frequency multiplier. In example implementations, an apparatus for generating a frequency includes a multimode frequency multiplier. The multimode frequency multiplier includes a multiphase generator and a reconfigurable frequency multiplier. The multiphase generator is configured to produce a first signal including multiple phase components and having a first frequency. The reconfigurable frequency multiplier is coupled in series with the multiphase generator. The reconfigurable frequency multiplier is configured to produce a second signal based on the first signal and having a second frequency that is a multiple of the first frequency.

The present disclosure generally relates to the field of receiver structures in radio communication systems and more specifically to passive mixers in the receiver structure and to a technique for converting a first signal having a first frequency into a second signal having a second frequency by using a third signal having a third frequency. A passive mixer for converting a first signal having a first frequency into a second signal having a second frequency by using a third signal having a third frequency comprises a cancellation component 220 for generating a first cancellation signal for cancelling second order intermodulation components by superimposing the first signal weighted by a cancellation value on the third signal; and a mixing component 231 having a first terminal 232 for receiving the first signal, a second terminal 234 for outputting the second signal, and a third terminal 236 for receiving the first cancellation signal, wherein the mixing component 231 is adapted to provide the second signal as output at the second terminal 234 by mixing the first signal provided as input at the first terminal 232 and the first cancellation signal provided as input at the third terminal 236.

A frequency multiplier includes an input section having inputs to receive an input signal having an input frequency, a mixer section, and an output section magnetically coupled to the input section and generating an output signal in response to the input signal. The mixer section may be coupled to the input section by a common mode node forming a path for a common mode current to flow to the mixer section and be magnetically coupled to the common mode node. The input section may generate a signal current, and the mixer section may be magnetically coupled to the input section and be directly capacitively coupled to the input section through a capacitor in a signal current path. The mixer section may have differential inputs capacitively coupled to the input section and also be coupled to the input section through a current path. A current helper section may be coupled to the current path.

A combined mixer and filter circuitry is disclosed. The combined mixer and filter circuitry comprises a mixer comprising a first input, a second input and an output. The combined mixer and filter circuitry further comprises a filter comprising an active inductor and a first capacitor. The active inductor comprises a transistor having a first terminal, a second terminal and a third terminal and a resistor connected between the first terminal of the transistor and a voltage potential. The first capacitor is connected between the third terminal and a signal ground and the second terminal of the transistor is connected to the second input of the mixer.

A method for calibrating a mixer, an apparatus using the calibrated mixer, and a method for using the apparatus to calibrate another mixer are disclosed. The method includes coupling a first RF signal characterized by a first timezero phase and a first RF frequency to the RF signal input. The method includes (a) coupling a first LO signal characterized by a first LO frequency and a first LO timezero phase to the LO signal input terminal; (b) determining an IF tone timezero phase of a tone from the IF signal output corresponding to the first LO signal; and (c) determining a first after LO signal path timezero phase from the IF tone and first LO timezero phase. Steps (a), (b), and (c) are repeated for second and third LO signals. An LO phase change as a function of frequency introduced by the LO signal path is then determined.

Mixers with improved linearity are disclosed. A diode or FET ring mixer is implemented with at least one parallel shunt element coupled with the ring mixer, the shunt element providing shunt to a diode or FET, for example, to reduce the effect of nonlinear or off resistance and/or capacitance. Linearity, isolation, symmetry, even order harmonics of the ring mixer, or any combination thereof can be improved as a result. The linearity of the ring mixer with parallel shunt resistors can be further improved by adding series resistors in the ring according to certain embodiments.

An electronic circuit includes adjustment units configured to receive a same oscillating signal having a predetermined frequency and to adjust a phase and an amplitude of the oscillating signal to produce output oscillating signals, coupling points configured to supply the output oscillating signals produced by the adjustment units to antennas, couplers provided in one-to-one correspondence with outputs of the adjustment units, equal-length lines sharing the same length and extending from the couplers, respectively, mixer circuits coupled to the equal-length lines, respectively, each of the mixer circuits being configured to receive a same reference oscillating signal having the predetermined frequency and a corresponding one of the output oscillating signals, and a control circuit configured to cause the adjustment units to adjust at least one of the phase and the amplitude in response to direct-current components in outputs of the mixer circuits.