In an embodiment, a circuit includes first, second, and third 90° hybrid couplers coupled between first and second antenna terminals, a pair of low-noise amplifiers (LNAs), and a pair of power amplifiers (PAs). The pair of LNAs is configured to receive first signals from the first and second antenna terminals and has an output configured to be coupled to a receive path. The second coupler is configured in power combiner mode for receiving the first signals. The pair of PAs is configured to transmit second signals via the first and second antenna terminals and has an input configured to be coupled to a transmit path. The third coupler is configured in power divider mode for transmitting the second signals.

Auto-balancing transformers are disclosed for balancing a multi-phase electrical system by varying the degree of electromagnetic coupling between primary and secondary windings. The auto-balancing transformer includes a movable armature to selectively couple primary phases with two or fewer phases of the secondary system.

Disclosed herein are implementations of a hybrid network for use in a full duplex communication system. In one aspect, the hybrid network includes a first circuit coupled between an output of a communication channel and a shared output of a transmitter and the communication channel, a second circuit coupled between a first output of the transmitter and the shared output, a third circuit coupled between the shared output and an input of an amplifier, a fourth circuit coupled between the input of the amplifier and a second output of the transmitter, and a fifth circuit coupled between an output of the amplifier and the input of the amplifier. In some embodiments, the output of the amplifier is coupled to an input of a receiver.

In certain aspects, a system includes a first filter, a second filter, a dummy load, and a switching circuit coupled to the first filter, the second filter, and the dummy load, and coupled to a first antenna and a second antenna. In a first mode, the switching circuit couples the first filter and the second filter to the first antenna, and, in a second mode, the switching circuit couples the first filter and the third filter to the first antenna and couples the second filter to the second antenna. In certain aspects, the dummy load includes a third filter.

The disclosure relates to arrangements for antenna interfaces configurable to efficiently support different communication modes. This is achieved by an antenna connection circuit 10 for a communication device 1 wherein the antenna connection circuit 10 is configurable for communication modes. The antenna connection circuit comprises a first quarter-wave transformer qw1 coupled between an antenna port A and an transmitter port Tx, and a second quarter-wave transformer qw2 coupled between the antenna port A and a receiver port Rx. The antenna connection circuit further comprises a first ground switch s1 coupled between the receiver port Rx and a first ground connection g1, and a second ground switch s2 is coupled between the transmitter port Tx and a second ground connection g2. The antenna connection circuit further comprises a resistor R and a resistor switch s3 coupled in series between the receiver port Rx and the transmitter port Tx, and an inverting amplifier switch s4 coupled between the receiver port Rx and an input port I1 of an inverting amplifier Amp1, and an output port O1 of the inverting amplifier Amp1 is coupled to the transmitter port Tx.

A vehicle communication tool for retrofitting a wired communication of an existing electronic control unit for a wireless communication is disclosed. The communication tool includes: a wireless communication module; at least one physical connector; and a processing unit arranged between the wireless communication module and the at least one physical connector to convert transmission signals between wired transmission via the at least one physical connector and wireless transmission via the wireless communication module.

A vehicle communication tool for retrofitting a wired communication of an existing electronic control unit for a wireless communication is disclosed. The communication tool includes: a wireless communication module; at least one physical connector; and a processing unit arranged between the wireless communication module and the at least one physical connector to convert transmission signals between wired transmission via the at least one physical connector and wireless transmission via the wireless communication module.

Techniques are provided for a multi-frequency sampling system. A system implementing the techniques according to an embodiment includes a first bandpass filter to filter a radio frequency (RF) signal to generate a first filtered signal in a first frequency band, and a second bandpass filter to filter the RF signal to generate a second filtered signal in a second frequency band. The system also includes a first analog to digital converter (ADC) operating at a first sampling frequency to convert the first filtered signal to a first digital signal and a second ADC operating at a second sampling frequency to convert the second filtered signal to a second digital signal. The first frequency band is selected to avoid a first Nyquist boundary zone associated with the first sampling frequency and the second frequency band is selected to avoid a second Nyquist boundary zone associated with the second sampling frequency.

According to embodiments, an example method for determining an analog-to-digital converter (ADC) output timing in a user equipment may include operating a switch in a first mode to route a system clock from an oscillator to an input of the ADC and determining a first ADC output timing based on a first set of ADC samples generated by the ADC. The method may also include operating the switch in a second mode to route analog signals from a transceiver of the user equipment to the input of the ADC and obtaining a second set of ADC samples generated by the ADC based on the analog signals.

Filters 10 and 20 having respective pass bands different from each other, a common terminal to which a terminal 11 of the filter 10 and a terminal of the filter 20 are connected, and an inductor of which one end is connected to the terminal 11 and another end is connected to the common terminal. The filter 10 includes a longitudinally coupled resonator formed of a resonator 132 and resonators 131 and 133 disposed on both sides of the resonator 132, in which the resonator 132 is connected to the terminal 11, and a parallel resonator of which one end is connected to the resonator 132 and another end is connected to a ground electrode, and the resonator 132 and the parallel resonator of the resonators included in the filter 10 are connected to a signal path between the resonator 132 and the terminal 11.