Coil antenna device and antenna module

A coil antenna device comprising:

• a core including a magnetic layer;
• and
• a coil conductor arranged in the core such that a portion of the magnetic layer defines a magnetic core and such that a coil axis extends along a principle surface of the core;
• wherein
• the coil conductor includes a line conductor portion extending along the principle surface of the core and a plurality of via-hole conductor portions extending in a thickness direction of the core so as to be surrounded by the magnetic layer;
• and
• at least a portion of the line conductor portion is disposed outside of the magnetic layer.

An antenna module comprising:

• a printed wiring board;
• a coil antenna device mounted on the printed wiring board;
• a plurality of wireless communication devices that perform wireless communication and are mounted on the printed wiring board;
• wherein
• the coil antenna device includes:
• a core including a magnetic layer;
• and
• a coil conductor arranged in the core such that a portion of the magnetic layer defines a magnetic core and such that a coil axis extends along a principle surface of the core;
• wherein
• the coil conductor includes a line conductor portion extending along the principle surface of the core and a plurality of via-hole conductor portions extending in a thickness direction of the core so as to be surrounded by the magnetic layer;
• and
• at least a portion of the line conductor portion is disposed outside of the magnetic layer.