A radio frequency (RF) summer circuit having a characteristic impedance Zo comprises first and second ports coupled by first and second resistances, respectively, to a junction. The circuit further comprises a series combination of a third resistance and a switch movable between open and closed positions and an amplifier having input and output terminals and operable in an off state and an on state wherein the series combination is coupled across the input and output terminals of the amplifier between the junction and a third port. The first resistance, second resistance, and the third resistance are all substantially equal to Z.sub.0/3. Further, when the switch is moved to the closed position and the amplifier is switched to the off state a passive mode of operation is implemented and when the switch is moved to the open position and the amplifier is switched to the on state an active mode of operation is implemented. The RF summer circuit develops a summed signal at the third port equal to a sum of signals at the first and second ports modified by one of first and second gain values.

An LNA having a plurality of paths, each of which can be controlled independently to achieve a gain mode. Each path includes at least an input FET and an output FET coupled in series. A gate of the output FET is controlled to set the gain of the LNA. Signals to be amplified are applied to the gate of the input FET. Additional stacked FETs are provided in series between the input FET and the output FET.

A circuit for controlling wireless transmissions. The circuit includes a multi-input logic gate coupled to a power amplifier for wireless transmission. A first input of the logic gate is coupled to a first wireless transceiver; and a second input of the gate is coupled to one or more wireless devices.

A high-frequency amplifier circuit has a source-grounded first transistor that amplifies a high-frequency input signal, a gate-grounded second transistor that further amplifies the amplified signal, a first inductor and a first reference voltage node, a second inductor connected between a first node and a second reference voltage node, a third transistor that is connected between the first node and a drain of the second transistor, is turned on at the time of selecting the first mode to transmit the amplified signal to the first node, and is turned off when selecting a second mode to disconnect the first node from the drain of the second transistor, a bypass path that bypasses the high-frequency input signal from an input node of the high-frequency input signal to the first node at the time of selecting the second mode, and a bypass switching circuit that is connected on the bypass path.

A front end module (FEM) for a 5.6/6.6 GHz Wi-Fi acoustic wave resonator RF filter circuit. The device can include a power amplifier (PA), a 5.6/6.6 GHz resonator, and a diversity switch. The device can further include a low noise amplifier (LNA). The PA is electrically coupled to an input node and can be configured to a DC power detector or an RF power detector. The resonator can be configured between the PA and the diversity switch, or between the diversity switch and an antenna. The LNA may be configured to the diversity switch or be electrically isolated from the switch. Another 5.6/6.6 GHZ resonator may be configured between the diversity switch and the LNA. In a specific example, this device integrates a 5.6/6.6 GHz PA, a 5.6/6.6 GHZ bulk acoustic wave (BAW) RF filter, a single pole two throw (SP2T) switch, and a bypassable LNA into a single device.

A power amplifier system is disclosed having a first amplifier with a high-power input and a high-power output. A second amplifier has a low-power input and a low-power output. A reconfigurable mode switch network has a first series switch branch coupled between the high-power output and an RF output, a first shunt branch is coupled between the RF output and a fixed voltage node, and a second series switch branch is coupled between the low-power output and a shared node of the first shunt branch. The shared node separates the first shunt branch into a first shared section that is between the RF output and the shared node and a second shared section that is between the shared node and the fixed voltage node.

Embodiments of this application disclose a radio frequency unit, an antenna, and a signal processing method. The method includes: receiving an uplink signal in a downlink slot, where the uplink signal includes signals of N frequency bands; filtering and amplifying the signals of the N frequency bands; converting the uplink signal into a digital intermediate frequency signal; and then processing the digital intermediate frequency signal.

A clamping circuit that may be used to provide efficient and effective voltage clamping in an RF front end. The clamping circuit comprises two series coupled signal path switches and a bypass switch coupled in parallel with the series coupled signal path switches. A diode is coupled from a point between the series coupled signal path switches to a reference potential. In addition, an output selection switch within an RF front end has integrated voltage clamping to more effectively clamp the output voltage from the RF front end. Additional output clamping circuits can be used at various places along a direct gain signal path, along an attenuated gain path and along a bypass path.

A front end module (FEM) for a 6.5 GHz Wi-Fi acoustic wave resonator RF filter circuit. The device can include a power amplifier (PA), a 6.5 GHz resonator, and a diversity switch. The device can further include a low noise amplifier (LNA). The PA is electrically coupled to an input node and can be configured to a DC power detector or an RF power detector. The resonator can be configured between the PA and the diversity switch, or between the diversity switch and an antenna. The LNA may be configured to the diversity switch or be electrically isolated from the switch. Another 6.5 GHZ resonator may be configured between the diversity switch and the LNA. In a specific example, this device integrates a 6.5 GHz PA, a 6.5 GHZ bulk acoustic wave (BAW) RF filter, a single pole two throw (SP2T) switch, and a bypassable LNA into a single device.

Techniques for providing low-cost and effective jammer rejection for an amplifier is disclosed. The amplifier includes an input node and an output node, a first transistor and a second transistor, a load circuitry, an inductor, and a capacitor. A first terminal of the first transistor is coupled to a ground. A second terminal of the first transistor is coupled to a first terminal of the second transistor. A second terminal of the second transistor is coupled to the output node. The load circuitry is coupled between a power supply and the second terminal of the second transistor. A first terminal of the inductor is coupled to the ground through a first switch. A first terminal of the capacitor is coupled to the first terminal of the second transistor and a second terminal of the capacitor is coupled to a second terminal of the inductor.