Methods related to radio frequency front end systems. In some embodiments, the method can include providing a first module configured to provide multi-input multi-output (MIMO) receive operations for a first plurality of mid bands and a first plurality of high bands. The first module can be further configured to provide transmit operations for the plurality of mid bands. The first module can include a first node. The method can include providing a second module configured to provide transmit and receive operations for a second plurality of mid bands and a second plurality of high bands. The second module can be a power amplifier integrated duplexer (PAiD) module. The second module can include a second node. The first module and the second module can be coupled by a signal path at the first node and the second node, respectively.

A multichannel transmission system which includes a calibration functionality that allows precise calibration of the frequency conversion chains and of the multiport amplifier of the system to be performed without interruption of service. The proposed calibration makes it possible to correct the defects over the entire frequency band of the system.

A circuit includes a first input and output terminals to which a current, a voltage, or an electromagnetic wave (referred to as “current or the like” below) is applied, a second input and output terminals to which the current or the like is applied, a first board including a matrix circuit which is formed by a first line and includes a 90-degree hybrid circuit and a delay line, the first line in which one end is connected to the first input and output terminals and a tip of the other end is opened, a second board including a second line in which one end is connected to the second input and output terminals, and a tip of the other end is opened, and a shielding plate including an opening portion.

A method of communication between first and second controllers positioned in spaced relation along a length of a vehicle system includes establishing first and second wireless, parallel communication channels between the first and second controllers. The channels operate at different carrier frequencies. The first controller transmits common information in parallel on the first and second wireless communication channels to the second controller, and the second controller receives the information transmitted in parallel on first and second wireless communication channels. The first and second wireless communication channels are then deactivated Subsequently, a single communication channel is established for communicating other, different information between the controllers.

A solid state power amplifier uses a Doherty power amplifier that can be implemented as a monolithic microwave integrated circuit. By adjusting the DC bias of the amplifying stages in each branch of the Doherty amplifier, the output power, linearity, and DC power can be adjusted to provide a specified output, where the specification for the output can include the maintaining of desired DC power and linearity. The Doherty power amplifier can be used in a satellite payload or other application utilizing solid state power amplifiers, while providing the proper amount of RF output power and DC power. A single amplifier can have its bias levels adjusted for different output levels, helping to minimize the number of designs that are required for a given satellite payload, reducing the variety of parts in a satellite payload.

A wireless device includes a phase control circuit and an antenna element. The phase control circuit configured to control each of phases frequencies of the plurality of transmission signals according to a transmission direction of which each the plurality of transmission signals is output, up-convert each frequencies of the plurality of transmission signals of which the phase is controlled. The antenna element configured to radiate a signal combing the up-converted plurality of transmission signals.

A switching circuit includes a first transmission terminal, a second transmission terminal, a third transmission terminal, and a variable impedance circuit. The first and the second transmission terminals coupled to a common node form a first transmission path. The third transmission terminal coupled to the common node forms a second transmission path with the first transmission terminal. The variable impedance circuit has a first terminal coupled between the common node and the third transmission terminal, and a second terminal coupled to a first reference potential terminal. When the first transmission path transmits a first signal, a first frequency bandwidth range provided by the variable impedance circuit is determined according to a first frequency of the first signal so that the variable impedance circuit provides low impedance in the first frequency bandwidth range, and the first frequency bandwidth range covers the first frequency.

A transmission system includes: an antenna; a control device including an RF circuit which transmits a first signal for controlling a radio wave to be outputted from the antenna and an external power supply which supplies direct current to the antenna; and a first transmission path which connects the antenna and the control device, and is used in transmission of the first signal and supplying of the direct current to the antenna.

A Radio Frequency (RF) circuit including a receive path, a transmit path, a switching circuit, and an output configured to receive RF signals from an antenna in a receive mode of operation, and to provide RF signals to the antenna in a transmit mode of operation. The receive path is configured to be coupled between a low-noise amplifier and the output. The switching circuit is located in the receive path and is configured, in the receive mode, to selectively couple the low-noise amplifier to the output and to pass the received RF signals from the output to the low-noise amplifier. The transmit path is configured to be coupled between a power amplifier and the output, to provide, in the transmit mode, signals from the power amplifier to the output, bypassing the switching circuit, and to have, in receive mode of operation, an off-state impedance of at least 200+j*13 Ohm.

A radio frequency module includes a module board, a transmission power amplifier, a first inductance element mounted on the module board and connected to an output terminal of the transmission power amplifier, a reception low noise amplifier, a first inductance element mounted on the module board and connected to an input terminal of the reception low noise amplifier, and a wall body made of plated metal and disposed on the module board. The wall body is disposed between the first inductance element and the second inductance element.