A receiver front end having low noise amplifiers (LNAs) is disclosed herein. A cascode having a “common source” configured input FET and a “common gate” configured output FET can be turned on or off using the gate of the output FET. A first switch is provided that allows a connection to be either established or broken between the source terminal of the input FET of each LNA. A drain switch is provided between the drain terminals of input FETs to place the input FETs in parallel. This increases the g.sub.m of the input stage of the amplifier, thus improving the noise figure of the amplifier.

A dual-frequency low-noise amplifier circuit includes an input impedance matching circuit, a radio-frequency signal amplifying circuit and an output impedance matching circuit. An input end of the input impedance matching circuit inputs a radio-frequency signal, and an output end is connected to an input end of the output impedance matching circuit by means of the radio-frequency signal amplifying circuit; an output end of the output impedance matching circuit outputs an amplified radio-frequency signal; a first band radio-frequency signal is amplified, input and output switches are in a first open and closed state, and input and output impedances are first input and output impedances; and a second band radio-frequency signal is amplified, the input and output switches are in a second open and closed state, and the input and output impedances are second input and output impedances. Adjusting the dual-frequency low-noise amplifier circuit can reduce signal reflection and improve signal quality.

A dual-band low-noise amplifier circuit includes an amplification sub-circuit and a switch frequency selection circuit; the amplification sub-circuit is used for performing gain amplification on a radio frequency signal to be amplified to obtain an amplified radio frequency signal, and outputting the amplified radio frequency signal; the switch frequency selection circuit is connected to the amplification sub-circuit, and is used for controlling the state of a switch in the switch frequency selection circuit on the basis of a target frequency band corresponding to the radio frequency signal to be amplified, so that the dual-band low-noise amplifier circuit meets optimal performance in the target frequency band. In this way, low-noise amplification of dual-band signals is achieved by means of the reconfigurable structure of the low-noise amplifier circuit, and parameters such as noise figure, gain, and linearity can be kept in optimal states in each frequency band.

A radio frequency circuit includes a transmit power amplifier, a differential transmit signal path having first and second paths, and first and second baluns. The first balun can be configured to convert a single ended transmit signal into a differential transmit signal, and the second balun can be configured to convert the differential transmit signal back to a single ended transmit signal. The circuit can also include a pair of transmit filters between the first and second baluns and including a first transmit filter connected in the first path and a second transmit filter connected in the second path. The second balun cancels harmonic noise generated by the pair of transmit filters.

An apparatus for reducing switching time of RF FET switching devices is described. A FET switch stack includes a stacked arrangement of FET switches and a plurality of gate feed arrangements, each coupled at a different height of the stacked arrangement. A circuital arrangement with a combination of a series RF FET switch and a shunt RF FET switch, each having a stack of FET switches, is also described. The shunt switch has one or more shunt gate feed arrangements with a number of bypass switches that is less than the number of FET switches in the shunt stack.

In a high-frequency module, a plurality of filters are connected to a first switch. A plurality of amplifiers are connected to a second switch. A first inductor is disposed on a common path between a second common terminal of the second switch and a first common terminal of the first switch. A plurality of second inductors are disposed, on a one-to-one correspondence, in sections different from the common path, the sections being included in the plurality of respective signal paths. The first inductor is a surface mount inductor located on a first main surface of a mounting substrate. The plurality of second inductors are each an inductor disposed within an IC chip including the plurality of amplifiers or an inductor including a conductive pattern formed in or on the mounting substrate.

Disclosed is a radio frequency circuit, a method of transmitting and receiving radio frequency signals, and a wireless communication device. The radio frequency circuit includes a first radio frequency amplifier, a second radio frequency amplifier, a first channel switch, a first low noise amplifier, a second low noise amplifier, and a second channel switch; the first radio frequency amplifier and the second radio frequency amplifier are connected with a plurality of antennas through the first channel switch, respectively, and are connected with a plurality of SRS antennas through an SRS switch in the first channel switch; the first low noise amplifier and the second low noise amplifier are connected with the plurality of antennas through the first channel switch, respectively, and are connected with a receiver through the second channel switch, respectively; wherein, the first radio frequency amplifier or the second radio frequency amplifier transmits one channel of radio frequency transmission signals to realize one-channel transmission, and the first low noise amplifier and the second low noise amplifier simultaneously receive radio frequency reception signals to realize two-channel reception.

A LNA comprises an input, a transformer structure and a first transistor and a second transistor, each having gate, source, and drain terminals. The transformer structure has a first winding pair, a second winding pair and a third winding pair. Each winding of the first winding pair connects to the input node and one source terminals of the transistors. The second winding pair is proximate the first winding pair. The second winding pair connects to a ground node and the transistor source terminals. The third winding pair is proximate the first winding pair and it connects to a bias signal source and a gate terminal of the transistors. An output connects to the transistor drain terminals. The windings of the first and second winding pairs are offset and rotated 180 degrees with respect to the other winding in the pair. The third winding pair performs a Gm boost function.

Aspects of this disclosure relate to acoustic wave filters with bulk acoustic wave resonators. An acoustic wave filter can include a first bulk acoustic wave resonator configured to excite an overtone mode as a main mode and a second bulk acoustic wave resonator having a fundamental mode as a main mode.

A low-power standard-compliant NB-IoT wake-up receiver (WRX) is presented. The WRX is designed as a companion radio to a full NB-IoT receiver, only operating during discontinuous RX modes (DRX and eDRX), which allows the full high-power radio to turn off while the wake-up receiver efficiently receives NB-IoTWake-Up Signals (WUS). The fabricated receiver achieves 2.1 mW power at −109 dBm sensitivity with 180 kHz bandwidth over the 750-960 MHz bands. The WRX is fabricated in 28 nm CMOS and consumes 5× less power than the best previously published traditional NB-IoT receivers. This disclosure is the first designed dedicated wake-up receiver for the NB-IoT protocol and demonstrates the benefits of utilizing a WRX to reduce power consumption of NB-IoT radios.