A multi-channel filter with a PCB with a first side with signalling tracks and shielding tracks between neighbouring signalling tracks. On the second side, a conductive layer is provided. The signalling tracks are covered by an electromagnetically absorbing material, such as a powder of an electrically conducting material is provided. The filter may have sections with reversed structure where the conductors are on the second side and the layer on the first side, where the conductors on opposite sides are interconnected. The filter may be rolled or folded.

A composite electronic component includes a multilayered body in which a plurality of dielectric layers and a plurality of conductor layers are alternately stacked, a first resonant circuit including a first line and a first capacitor, the first line being formed of one or more first conductor layers of the conductor layers, the first capacitor including a first electrode formed of a plurality of second conductor layers of the conductor layers, and a second resonant circuit including a second line and a second capacitor, the second line being formed of one or more third conductor layers of the conductor layers, the second capacitor including a second electrode formed of the second conductor layers, the second conductor layers being located between the one or more first conductor layers and the one or more third conductor layers.

A multi-layer waveguide including at least three physical layers assembled into a multi-layer waveguide. The layers are a top layer, one or more intermediate layer, and a bottom layer. The multi-layer waveguide further includes a waveguide channel being an elongated aperture in at least one intermediate layer. At least one layer has a metasurface on a first surface facing a first adjoining layer, wherein the metasurface surrounds the elongated aperture and comprise thick and thin sections.

An object of this invention is to reduce the size of a filter device. Provided is a filter device (1) including: a substrate (11) including a first main surface and a second main surface (111, 112); strip-shaped conductors (12a1 to 12a5) provided to the first main surface (111); and a ground conductor layer (13) provided at least to the second main surface (112), the second main surface (112) having a recessed portion (11ai) provided for each strip-shaped conductor (12ai), the recessed portion (11ai) overlapping the strip-shaped conductor (12ai) in plan view and having a surface covered with the ground conductor layer (13).

A multilayered filter device includes a multilayer stack, a band pass filter, a first band elimination filter, and a second band elimination filter. The band pass filter and the first and second band elimination filters are each constructed using the multilayer stack. The band pass filter includes a plurality of first resonators with open ends. Each band elimination filter includes a connection path, and a second resonator coupled to the connection path. The connection path includes an impedance transformer. The second resonator includes a conductor line constituting a distributed constant line.

A filter comprising a flexible PCB with one or more signal tracks on one side. A electromagnetically absorbing material covers the signal tracks. An insulating material may be provided between the signal tracks and the electromagnetically absorbing material. The PCB is then folded or rolled to take up less space. The PCB may be first folded and then rolled to have both ends of the signal tracks available at the outer portion of the roll.

Described is a bandpass filter comprising a multi-layered body, a first resonator conductor formed on a first layer of the body and a second resonator conductor formed on a second, tower layer of the body. The first resonator conductor and the second resonator conductor comprise a first coupling area formed by only a partial overlap of the first resonator conductor and the second resonator conductor. A length of each said resonator conductor is in the range of λ.sub.g/3 to λ.sub.g/5, where λ.sub.g. is a center wavelength of the bandpass filter passband.

A multilayer substrate module includes a first substrate portion including a first substrate portion body including first insulator layers stacked in a vertical direction and a first conductor layer and/or a first interlayer connection conductor provided at the first substrate portion body. A second substrate portion includes a second substrate portion body including second insulator layers stacked in the vertical direction and a second conductor layer and a second interlayer connection conductor provided at the second substrate portion body, and is mounted on an upper surface of the first substrate portion. A mount device is mounted on an upper surface or a lower surface of the second substrate portion. At least a portion of an inductance component is defined by the first conductor layer and the first interlayer connection conductor.

A filter device includes a stack including a plurality of dielectric layers stacked together, and first to third resonators integrated with the stack. Each of the first to third resonators includes a first conductor part and a second conductor part electrically connected to the first conductor part and having an impedance smaller than an impedance of the first conductor part. The first conductor part and the second conductor part are arranged at positions different from each other in a stacking direction.

A filter device includes first to third resonators. Each of the first to third resonators includes a first line part and a second line part electrically connected to the first line part and having an impedance smaller than an impedance of the first line part. The impedance ratio in at least one of the first to third resonators is 0.3 or smaller. The shape of each of the second line part of the first resonator and the second line part of the second resonator is long in a direction orthogonal to a stacking direction and crossing the longitudinal direction of the second line part of the third resonator.