According to one embodiment, a power divider includes a first transmission line, a first input transmission line, a second input transmission line, and the plurality of output transmission lines. The first transmission line has a closed structure. The first input transmission line and the second input transmission line are connected to the first transmission line at locations away from each other along the first transmission line by approximately a quarter of a length of the first transmission line. The plurality of output transmission lines are connected to the first transmission line at locations dividing the length of the first transmission line substantially evenly.

A hybrid coupler includes a 90° hybrid coupler and a first quarter wavelength conductive stub. The 90° hybrid coupler includes a coupling section, a first input transmission line that is coupled to the coupling section, a second input transmission line that is coupled to the coupling section, a first output transmission line that is coupled to the coupling section and a second output transmission line that is coupled to the coupling section. The first quarter wavelength conductive stub is coupled to the second output transmission line.

A high-speed circuit assembly includes a high-speed circuit including at least one waveguide/transmission line, and a radiation absorbing material disposed in contact with or in close proximity with the waveguide/transmission line.

An antenna system. The antenna system includes a central antenna, and a plurality of peripheral antennas positioned symmetrically around the central antenna. A first coupler provides a first radio connection and a second radio connection. A first 180 degree hybrid coupler is coupled to a first two diametrically opposed antennas of the plurality of peripheral antennas. A second 180 degree hybrid coupler is coupled to a second two diametrically opposed antennas of the plurality of peripheral antennas. A third 180 degree hybrid coupler coupled to the first and second 180 degree hybrid couplers, and having a third radio connection and a fourth radio connection. The first, second, third, and fourth radio connections are decoupled from each other, and the first, second, and third system radio connections are also decoupled from the central antenna.

A device and a method for creating and/or maintaining an obstruction free upper respiratory passages. The device is configured to fit under the chin of a subject adjacent to the subject's neck at an external location corresponding approximately with the subject's internal soft tissue associated with the neck's anterior triangle. The device is capable of exerting negative pressure on the surface of a subject's neck, displacing the soft tissue forward and enlarging the airway.

A coupled-line rat-race coupler includes four ports and four coupled-lines each composed of two metal lines. Two of the ports are respectively connected with the front ends of the two lines of the first coupled-line, and the other two ports are respectively connected with the front ends of the two lines of the second coupled-line. The two lines of the third coupled-line are short circuited and respectively connected with the back end of one line of the first coupled-line on one side and with the back end of one line of the second coupled-line on the other side. In the fourth coupled-line, one line is open at one end and short circuited at the other end with the other line, which is connected with one line of the first coupled-line and one line of the second coupled-line. The coupled-line rat-race coupler is characterized with smooth and stable output phase.

An electronic switch for switching between signal outputs comprises a 6-way symmetric hybrid ring combiner. Each port within the 6-way symmetric hybrid ring combiner is positioned at λ/4 wavelength increments around a circumference of the 6-way symmetric hybrid ring combiner.

Examples disclosed herein relate to a vector modulator architecture, having an input splitter network configured to receive a radio frequency (RF) input signal and generate a plurality of quadrature signals at different phases, a variable gain amplifier (VGA) stage coupled to the input splitter network and configured to apply a first gain to one or more of the plurality of quadrature signals, a power combiner coupled to the VGA stage and configured to combine the plurality of quadrature signals into a combined RF signal, and a power amplifier (PA) stage coupled to the power combiner and configured to apply a second gain to the combined RF signal and generate an output RF signal. Other examples disclosed herein relate to an antenna system for autonomous vehicles and a radar system for use in an autonomous driving vehicle.

A high-speed circuit assembly includes a high-speed circuit including at least one waveguide/transmission line, and a radiation absorbing material disposed in contact with or in close proximity with the waveguide/transmission line.

A high frequency power divider circuit for distributing an input signal to two or more signal output ports, comprising: a rat race coupler, wherein the rat race coupler is configured to couple an input signal provided at an input port of the rat race coupler to a first output of the rat race coupler and to a second output of the rat race coupler; a first coupling structure coupled to the first output of the rat race coupler, to couple the first output of the rat race coupler with a first signal output port; and a second coupling structure coupled to the second output of the rat race coupler, to couple the second output of the rat race coupler with a second signal output port; wherein a characteristic impedance of a first transmission line portion between the input port and the first output of the rat race coupler deviates from a nominal ring impedance of the rat race coupler in a first direction, and wherein a characteristic impedance of a second transmission line portion between the input port and the second output of the rat race coupler deviates from the nominal ring impedance of the rat race coupler in a second direction, which is opposite to the first direction.