Wireless communication antenna
A wireless communication antenna includes a solenoid coil portion including a core; and a magnetic body disposed in the core and comprising magnetic pieces arranged side by side in a direction perpendicular to or a direction parallel to a direction of a magnetic flux of the coil portion.
1. A wireless communication antenna, comprising:
a solenoid coil portion comprising a core;
a magnetic body serving as the core, the magnetic body including a plurality of magnetic layers stacked in a direction perpendicular to or a direction parallel to a direction of a magnetic flux of the solenoid coil portion;
the plurality of magnetic layers including a first magnetic layer having a plurality of first magnetic pieces and first interfaces formed between respective adjacent ones of the plurality of first magnetic pieces; and
the plurality of magnetic layers including a second magnetic layer having a plurality of second magnetic pieces and second interfaces formed between adjacent ones of the plurality of second magnetic pieces, the second magnetic layer stacked on the first magnetic layer, the first interfaces not aligning with the second interfaces.
2. The wireless communication antenna of claim 1 , wherein
the magnetic layers are stacked in the direction perpendicular to the direction of the magnetic flux of the solenoid coil portion, and
each of the magnetic lavers has a rod shape extended in the direction parallel to the direction of the magnetic flux.
3. The wireless communication antenna of claim 2 , wherein a width of each of the magnetic lavers is 0.5 mm to 5 mm.
4. The wireless communication antenna of claim 1 , wherein the magnetic layers are stacked in the direction parallel to the direction of the magnetic flux of the solenoid coil portion.
5. The wireless communications antenna of claim 1 , wherein the magnetic layers are stacked in another direction perpendicular to the direction of the magnetic flux of the solenoid coil portion.
6. The wireless communication antenna of claim 1 , wherein
both the first magnetic pieces and the second magnetic pieces are arranged in the direction parallel to the direction of the magnetic flux of the solenoid coil portion.
7. The wireless communication antenna of claim 1 , wherein a magnetostriction coefficient of the magnetic body is 5 or more.
8. The wireless communication antenna of claim 1 , wherein
the solenoid coil portion comprises a first wiring portion on a first surface of the magnetic body,
a second wiring portion on a second surface of the magnetic body, and
conductive vias are configured to connect the first wiring portion to the second wiring portion.
9. The wireless communication antenna of claim 8 , wherein each of the first wiring portion and the second wiring portion comprises a conductive pattern on a thin film substrate.
10. The wireless communication antenna of claim 8 , further comprising:
a resin layer at an outer edge of the magnetic body,
wherein the conductive vias pass through the resin layer.