In various implementations, designs of relatively simple ultra-wideband STAR front-end systems are provided. For example, such systems may include implementations utilizing a plurality of antenna arms in which a first portion of the arms is configured to transmit and a second portion of the arms is configured to receive. In one implementation, for example, a co-channel simultaneous transmit and receive (STAR) monostatic aperture configuration includes a single-polarized multi-port monostatic co-channel simultaneous transmit and receive (c-STAR) spiral antenna aperture. Other examples are also provided.

An impedance tuning circuit includes a first node and a second node, and an inductance circuit including an inductor and a first switch connected in series such that the inductor is connected to the first node and the first switch is connected to the second node. The inductance circuit further includes a second switch implemented between ground and a third node between the inductor and the first switch, such that the inductance circuit is capable of providing a series inductance path between the first and second nodes or a shunt inductance path between the third node and the ground.

Apparatus and methods for power amplifier output matching is disclosed. In one aspect, there is provided an output matching circuit including an input configured to receive an amplified radio frequency signal from a power amplifier, a first output, and a second output. The output matching circuit further includes a first matching circuit electrically connected between the input of the output matching circuit and the first output, the first matching circuit configured to suppress harmonics of a fundamental frequency of the amplified radio frequency signal when the amplified radio frequency signal is within a first band. The output matching circuit further includes a second matching circuit electrically connected between the input of the output matching circuit and the second output, the second matching circuit configured to suppress harmonics of the fundamental frequency of the amplified radio frequency signal when the amplified radio frequency signal is within a second band different from the first band.

A power amplifier module can be formed that includes metamaterial matching circuits. This power amplifier module can be included as part of a front-end module of a wireless device. The front-end module can replace a passive duplexer with an active duplexer that uses the power amplifier module in combination with a low noise amplifier circuit that can include a metamaterial matching circuit. The combination of PA and LNA circuits that utilize metamaterials can provide the functionality of a duplexer without including a stand-alone or passive duplexer. Thus, in certain cases, the front-end module can provide duplexer functionality without including a separate duplexer. Advantageously, in certain cases, the size of the front-end module can be reduced by eliminating the passive duplexer. Further, the loss introduced into the signal path by the passive duplexer is eliminated improving the performance of the communication system that includes the active duplexer.

A system that incorporates teachings of the subject disclosure may include, for example, a communication device including a matching network for impedance tuning and pairs of antennas that can be utilized as primary and diversity antennas, respectively, and can provide high radiation efficiency. An RF switch can be utilized for re-configuring the primary and diversity antennas. Other embodiments are disclosed.

A circuit device includes a directional coupler with a first port receiving a radiofrequency signal, a second port outputting a signal in response to signal received by the first port, and a third port outputting a signal in response to a reflection of the signal at the second port. An impedance matching network is connected between the second port and an antenna. The impedance matching network includes fixed inductive and capacitive components and a single variable inductive or capacitive component. A diode coupled to the third port of the coupler generates a voltage at a measurement terminal which is processed in order to select and set the inductance or capacitance value of the variable inductive or capacitive component.

A wireless communication device includes a signal generator supply a signal to an input node to which a power amplifier is connected. The power amplifier includes an inverter including a first transistor with a gate connected to the input node via a first signal path and a second transistor with a gate electrode connected to the input node via a second signal path. An output signal corresponding to the signal supplied to the input node is supplied from an output node between the first and second transistors. A filter is connected to the output node and outputs a filtered signal having a high frequency component removed. A bias application unit applies a first bias voltage to the first signal path and a second bias voltage to the second signal path. Levels of the bias voltages being set according to a direct current component in the filtered signal.

A wideband power attenuator in RF-MEMS multilayer technology, for attenuating an electromagnetic signal, includes an upper layer with two RF ground planes, and between said two RF ground planes a central RF-MEMS movable switch as a floating electrode, an RF input, an RF output of an RF line running across the attenuator, a number of lower layers including in sequence: a ground floor of an electrically insulating substrate; two DC biasing electrodes to electrostatically control said movable switch, and DC biasing lines to feed the DC biasing electrodes; two DC-RF decoupling resistors, each decoupling resistor being connected on one side to respective terminals of said movable switch, and on the other side to respective one of the two RF ground planes; a resistive load adapted to be connected to the RF line to attenuate the electromagnetic signal on the basis of the floating movable switch configuration, between a non-contact RF position and a contact RF position with said RF line.

A radar transceiver is provided. The radar transceiver includes an electrical balance duplexer that is coupled to a transmission node of a transmission path, a reception node of a reception path, and an antenna node and that is configured to isolate the transmission path from the reception path. The electrical balance duplexer includes a hybrid transformer network and a non-tunable balancing impedance. The non-tunable balancing impedance is configured to provide a fixed impedance value that corresponds to an impedance value at the antenna node.

A transceiver includes: a radio-frequency (RF) front-end circuit; a dedicated RF front-end circuit; and a switchable matching circuit, integrated in a chip. The RF front-end circuit deals with communications of a first wireless standard, and the dedicated RF front-end circuit deals with communications of a second wireless standard. The switchable matching circuit provides impedance matching between the signal port and the RF front-end circuit when the RF front-end circuit is in operation, and provides impedance matching between the signal port and the dedicated RF front-end circuit when the dedicated RF front-end circuit is in operation, and includes: a first capacitive circuit coupled to the signal port; a first switch circuit coupled between the first capacitive circuit and the dedicated RF front-end circuit; a second capacitive circuit coupled to the dedicated RF front-end circuit; and a second switch circuit coupled to a second terminal of the second capacitive circuit.