Impedance matching device and communication device

An impedance matching device, including:

• a first dielectric substrate;
• a first transmission line circuit, which is provided on a first side of the first dielectric substrate, a first end of the first transmission line circuit being configured to receive a first signal;
• a first conductive pad, which is electrically connected to a second end of the first transmission line circuit and extends toward the first transmission line circuit on a second side opposite the first side of the first dielectric substrate so as to at least partially vertically overlap the first transmission line circuit;
• a first reference potential layer, which is provided on the second side of the first dielectric substrate and separated from the first conductive pad by a first gap;
• and
• a first matching load, which is electrically connected to the first conductive pad and has a first resistance value;
• wherein the first gap has a substantially constant width and an inductive effect of the first gap is configured to substantially offset a capacitance between the signal transmission line circuit and the first reference potential layer.

An impedance matching device, including:

• a first dielectric substrate;
• a first transmission line circuit, which is provided on a first side of the first dielectric substrate, a first end of the first transmission line circuit being configured to receive a first signal;
• a first conductive pad, which is electrically connected to a second end of the first transmission line circuit and extends toward the first transmission line circuit on a second side opposite the first side of the first dielectric substrate so as to at least partially vertically overlap the first transmission line circuit;
• a first reference potential layer, which is provided on the second side of the first dielectric substrate and separated from the first conductive pad by a first gap;
• and
• a first matching load, which is electrically connected to the first conductive pad and has a first resistance value;
• wherein a first vertical overlap area where the first conductive pad vertically overlaps the first transmission line circuit has a size configured such that a load reactance value associated with the first transmission line circuit is equal to or less than a predetermined reactance threshold and an absolute value of a difference between a load resistance value associated with the first transmission line circuit and the first resistance value is equal to or less than a predetermined resistance threshold,
• wherein the impedance matching device further includes:
• a third transmission line circuit, which is provided on the first side of the first dielectric substrate, a first end of the third transmission line circuit being configured to receive a third signal;
• a third conductive pad, which is electrically connected to a second end of the third transmission line circuit and extends toward the third transmission line circuit on the second side of the first dielectric substrate so as to at least partially vertically overlap the third transmission line circuit, a third gap being between the third conductive pad and the first reference potential layer to prevent the third conductive pad from being short-circuited with the first reference potential layer, the third conductive pad being electrically connected to the first matching load;
• wherein a third vertical overlap area where the third conductive pad vertically overlaps the third transmission line circuit has a size configured such that a load reactance value associated with the third transmission line circuit is equal to or less than the predetermined reactance threshold and an absolute value of a difference between a load resistance value associated with the third transmission line circuit and the first resistance value is equal to or less than the predetermined resistance threshold.