A wiring substrate includes a first insulating layer with a first opening, a second insulating layer with a second opening, a high-frequency wiring layer, a first wiring layer, a second wiring layer, and a plurality of conductive pillars. The high-frequency wiring layer including a high-frequency trace is sandwiched between the first insulating layer and the second insulating layer. The first opening and the second opening expose two sides of the high-frequency trace respectively. The high-frequency trace has a smooth surface which is not covered by the first insulating layer and the second insulating layer and has the roughness ranging between 0.1 and 2 μm. The first insulating layer and the second insulating layer are all located between the first wiring layer and the second wiring layer. The conductive pillars are disposed in the second insulating layer and connected to the high-frequency trace.

Electromagnetic circuit structures and methods are provided for a circuit board that includes a hole disposed through a substrate to provide access to an electrical component, such as a signal trace line (or stripline), that is at least partially encapsulated (e.g., sandwiched) between substrates. The electrical component includes a portion substantially aligned with the hole, and an electrical conductor is disposed within the hole. The electrical conductor is soldered to the portion of the electrical component.

Provided is a resin composition having excellent dielectric characteristics, i.e., low dielectric characteristics, in the high-frequency region, and excellent dielectric characteristics, i.e., low dielectric characteristics, under high humidity, and having practical adhesion to metal and resin substrates. More specifically, provided is a resin composition comprising an acid-modified polyolefin, an epoxy resin, and an inorganic filler, wherein a cured product of the resin composition has a dielectric loss tangent of 0.003 or less at a frequency of 10 GHz at 25° C. after storage for 168 hours under conditions of 85° C. and 85% RH (relative humidity).

This document describes techniques, apparatuses, and systems for an antenna-to-printed circuit board (PCB) transition. An apparatus (e.g., a radar system) may include an MMIC or other processor to generate electromagnetic signals. The apparatus can include a PCB that includes multiple layers, a first surface, and a second surface that is opposite and in parallel with the first surface. The PCB can also include a dielectric-filled portion formed between the first surface and second surface. The apparatus can also include a conductive loop located on the first surface and connected to a pair of lines. The apparatus can further include a transition channel mounted on the first surface and positioned over the dielectric-filled portion. The described transition can reduce manufacturing costs and board sizes, reduce energy losses, and support a wide bandwidth.

System, methods, and other embodiments described herein relate to using a printed conductor and a rectifier in the same enclosure for transferring power. In one embodiment, an apparatus includes a conductor, printed on a substrate housed in an enclosure, that generates alternating current caused by a magnetic field emitted by a transmitter, wherein the conductor is a trace spanning layers. The apparatus also includes a rectifier, on a device housed in the enclosure, that receives the alternating current through a terminal connected with the conductor and converts the alternating current to a direct current for powering a load, wherein an insulator between the conductor and the rectifier isolates the magnetic field.

A radio frequency (RF) jamming device includes a differential segmented aperture (DSA), a jammer source outputting a jamming signal at one or more frequencies or frequency bands to be jammed, and RF electronics that amplify and feed the jamming signal to the DSA so as to emit a jamming beam. The DSA includes an array of electrically conductive tapered projections, and the RF electronics comprise power splitters configured to split the jamming signal to aperture pixels of the DSA. The aperture pixels comprise pairs of electrically conductive tapered projections of the array of electrically conductive tapered projections. The RF electronics further comprise pixel power amplifiers, each connected to amplify the jamming signal fed to a single corresponding aperture pixel of the DSA. The RF jamming device may include a rifle-shaped housing, with the DSA mounted at a distal end of the barrel of the rifle-shaped housing.

A printed circuit board includes a dielectric substrate; first and second conductive traces disposed on the dielectric substrate; and a compensation structure disposed in the first conductive trace. The compensation structure includes a compensation segment connected in line with the first conductive trace; and a dielectric layer on all or part of the compensation segment. The first and second conductive traces may form a differential signal pair. The compensation segment may limit one or more of signal skew, mode conversion from differential mode to common mode, and impedance variations caused by a bend in the differential signal pair.

Various examples related to microwave dielectric analyzers and their use are provided. In one example, a microwave dielectric analyzer includes a measurement apparatus having a conductive electrode that can couple to a microwave analyzer and processing circuitry that can determine a dielectric characteristic of the dielectric specimen using a reflection coefficient measured by the microwave analyzer. The dielectric characteristic can be determined using a computational electromagnetic model of the measurement apparatus. The reflection coefficient can be measured by the microwave analyzer with the dielectric specimen in contact with the conductive electrode and/or sandwiched between conductive electrodes. The conductive electrodes can be axially aligned, and the second electrode may not be coupled to the microwave analyzer.

A porous polyimide film has a low dielectric loss tangent. The porous polyimide film is a reaction product of a diamine component and an acid dianhydride component. The diamine component contains an aromatic diamine represented by the following formula (1).

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(In formula, Y represents at least one selected from the group consisting of a single bond, —COO—, —S—, —CH(CH.sub.3)—, —C(CH.sub.3).sub.2—, —CO—, —NH—, and —NHCO—.) The porosity is 50% or more.

A porous polyimide film is provided to suppress an increase in a dielectric loss tangent even when immersed in water. In the porous polyimide film, a difference between a dielectric loss tangent T1 after being left to stand for 24 hours under an atmosphere of 25° C. and relative humidity of 50% and a dielectric loss tangent T2 after immersion in water for 24 hours under an atmosphere of 25° C. is 0.0030 or less.