A notch filter 100 includes a varistor 1 that is connected between a signal line SL and a ground G. The varistor 1 has a capacitive component and outputs a signal with a second frequency different from a signal with a first frequency flowing in the signal line SL and a signal with the second frequency superimposed on the signal line SL to the ground G.

An electromagnetic interference filter (EIF) system/method configured to maximize filter performance associated with EIF interconnects is disclosed. The disclosed system eliminates the use of conventional printed circuit board (PCB) interconnects and associated electrical connection terminals by attaching EIF filter capacitors and other components directly to power supply bus bars using a mechanical design and plastic encapsulating cover (PEC) that reduces parasitic inductances between the various EIF components while maximizing series inductance between +BUS/+CON connections and −BUS/−CON connections respectively through a permeable inductor core (PIC). The system/method may be applied to a variety of EIF applications including those associated with electric vehicles and the like.

An interdigitated RF filter. The interdigitated RF filter includes input fingers connected to an input node and output fingers connected to an output node where at least one input finger is connected the output node or at least one output finger is connected to the input node. The described interdigitated RF filter can be implemented in various configurations such as series, shunt, ladder or a combination thereof.

An interdigitated RF filter. The interdigitated RF filter includes input fingers connected to an input node and output fingers connected to an output node where at least one input finger is connected the output node or at least one output finger is connected to the input node. The described interdigitated RF filter can be implemented in various configurations such as series, shunt, ladder or a combination thereof.

The present subject matter provides technical solutions for the technical problems facing cryogenic ion traps by providing a cryogenic radio-frequency (RF) resonator that is compact, monolithic, modular, and impedance-matched to a cryogenic ion trap. The cryogenic RF resonator described herein is power-efficient, properly impedance-matched to the RF source, has a stable gain profile, and is compatible with a low temperature and ultra-high vacuum environment. In some examples, the gain profile is selected so that the cryogenic RF resonator acts as a cryogenic RF amplifier. This cryogenic RF resonator improves the performance of ion traps by reducing or minimizing the heat load and reducing or minimizing the unwanted noise that may erroneously drive trapped ions. These features of the present subject matter improve the performance of atomic clocks and mass spectrometers, and especially improve the performance of trapped ion quantum computers.

An integrated isolator circuit for isolating receiver and transmitter in a Time-Division Duplex transceiver is disclosed. The integrated isolator circuit comprises a first node, a second node and. a third node. The integrated isolator circuit further comprises a first capacitor connected in series with a first switch and connected between the first and second nodes. The integrated isolator circuit further comprises a first inductor connected between the first and second nodes and a second capacitor connected between the second node and the third node. The first switch has an on state and an off state, and the integrated isolator circuit is configured to have a different impedance at a certain operating frequency by controlling the state of the first switch.

Polyphase filters (PPFs) can be used to generate quadrature or other phase-shifted representations of an input signal provided to the PPF. In one approach, a “passive” polyphase filter can include a combination of resistive and capacitive elements. Such a topology can be referred to as an RC-PPF topology. Another passive circuit topology can be used to provide a PPF, by replacing the resistive elements with inductive elements, and by replacing the capacitive elements with resistive elements. A filter circuit can include cascaded RC-PPF and LR-PPF sections, such as in an alternating manner (e.g., an “RC-LR” topology). In this approach, a total insertion loss of cascaded LR-PPF and RC-PPF sections can be reduced as compared to using LR-PPF or RC-PPF sections, alone.

A filtering circuit includes at least two common-mode filters that are electrically coupled in series and magnetically coupled. The first common-mode filter includes first and second spiral inductors that are positively magnetically coupled and electrically isolated from each other. The second common-mode filter includes third and fourth spiral inductors that are positively magnetically coupled and electrically isolated from each other. The first and third spiral inductors are electrically connected in series and negatively magnetically coupled. Likewise, the second and fourth spiral inductors are electrically connected in series and negatively magnetically coupled.

The present subject matter provides technical solutions for the technical problems facing cryogenic ion traps by providing a cryogenic radio-frequency (RF) resonator that is compact, monolithic, modular, and impedance-matched to a cryogenic ion trap. The cryogenic RF resonator described herein is power-efficient, properly impedance-matched to the RF source, has a stable gain profile, and is compatible with a low temperature and ultra-high vacuum environment. In some examples, the gain profile is selected so that the cryogenic RF resonator acts as a cryogenic RF amplifier. This cryogenic RF resonator improves the performance of ion traps by reducing or minimizing the heat load and reducing or minimizing the unwanted noise that may erroneously drive trapped ions. These features of the present subject matter improve the performance of atomic clocks and mass spectrometers, and especially improve the performance of trapped ion quantum computers.

Provided is a low-leakage automatic adjustable diplexer including a body, a thin plate and two resonant regulators. The body has therein cuboid waveguide channels each having a feeding portion, a reception port portion, a transmission port portion, a fitting portion, a first filtering portion, a second filtering portion, first E/H conversion units connected to two ends of the first filtering portion, respectively, and second E/H conversion units connected to two ends of the second filtering portion, respectively. The thin plate is clamped inside the body. The resonant regulators each have a plurality of frequency disturbance elements adjustably protruding into the first and second filtering portions. Given the E/H conversion units and the frequency disturbance elements penetratingly disposed on the H-side sidewall of the cuboid waveguide cavity, it is unnecessary for the cuboid waveguide channels to undergo any processing process for forming therein any protrusion-style insulation walls, thereby attaining low leakage.