Antenna module and portable communication terminal equipped with the antenna module
An antenna module and a portable communication terminal equipped with the antenna module are provided. The antenna module has a space-saving design, and also has both a capability for long communication distance for a tag function and a capability for wide communication range for a reader/writer function. A first antenna coil ( 11 ) for communication with a reader/writer and a second antenna coil ( 12 ) for communication with an IC tag are disposed on a base substrate ( 10 ). The first antenna coil ( 11 ) is disposed in an outermost periphery section of the base substrate ( 10 ) so that a communication distance is attained. The second antenna coil ( 12 ) is disposed within an inner periphery of the first antenna coil ( 11 ) so as to achieve overall size reduction of the module.
1. An antenna module comprising:
a substrate having a communication surface opposite a main surface;
a first antenna coil disposed on the communication surface of the substrate and configured to communicate with a reader/writer;
a second antenna coil disposed on the main surface of the substrate inside the first antenna coil and configured to communicate with an IC tag;
a magnetic sheet bonded to the main surface of the substrate and the second antenna coil; and
a metallic plate bonded to the main surface of the substrate via the magnetic sheet,
wherein,
the first antenna coil and second antenna coil are separated by a distance which prevents magnetic coupling of the two antenna coils,
the first antenna is configured to communicate over a wider range of frequencies than the second antenna, and
the second antenna is configured to communicate over a longer distance than the first antenna, and
the second antenna coil is disposed between the magnetic sheet and the main surface of the substrate.
2. The antenna module according to claim 1 , wherein the first and second antenna coils are disposed within a plane of the substrate, and one of the antenna coils is disposed within an inner periphery of the other antenna coil.
3. The antenna module according to claim 1 , where a plurality of one or each of the first antenna coil and the second antenna coil are disposed on the substrate.
4. An antenna module comprising:
a substrate having a communication surface opposite a main surface;
a first antenna coil disposed on the communication surface of the substrate and is configured to communicate with a reader/writer;
a second antenna coil disposed on the main surface of the substrate and is configured to communicate with an IC tag;
a magnetic sheet bonded to the main surface of the substrate and the second antenna coil;
a metallic plate bonded to the main surface of the substrate via the magnetic sheet; and
a signal processing circuit disposed on the main surface of the substrate and including an IC storage medium storing data to be transmitted via the first and second antenna coils,
wherein,
the first antenna coil and second antenna coil are separated by a distance which prevents magnetic coupling between them,
the first antenna is configured to communicate over a wider range of frequencies than the second antenna, and
the second antenna is configured to communicate over a longer distance than the first antenna, and
the second antenna coil is disposed between the magnetic sheet and the main surface of the substrate.
5. The antenna module according to claim 4 , wherein the substrate is provided with a wave absorber covering the signal processing circuit.
6. The antenna module according to claim 5 , wherein a surface of the wave absorber is provided with a metallic layer.
7. The antenna module according to claim 4 , wherein:
one of antenna coils is disposed within an inner periphery of the other antenna coil, and
the signal processing circuit is disposed within the inner periphery of said other antenna coil.
8. The antenna module according to claim 7 , wherein the substrate includes a combination of an annular antenna holding substrate portion for holding the first and second antenna coils and a circuit holding substrate portion for holding the signal processing circuit.
9. The antenna module according to claim 8 , wherein the substrate is provided with a wave absorber covering the signal processing circuit.
10. The antenna module according to claim 9 , wherein a surface of the wave absorber is provided with a metallic layer.
11. The antenna module according to claim 4 , wherein the magnetic sheet is provided with an opening in which the signal processing circuit on the substrate is held.
12. The antenna module according to claim 11 , wherein the substrate is provided with a wave absorber covering the signal processing circuit.
13. The antenna module according to claim 12 , wherein a surface of the wave absorber is provided with a metallic layer.
14. The antenna module according to claim 4 , wherein a plurality of one or each of the first antenna coil and the second antenna coil are disposed on the substrate.
15. A portable communication terminal having a function for data communication via a communication network, comprising:
an antenna module including a substrate with a communication surface opposite a main surface, a first antenna coil on the communication surface configured to communicate with a reader/writer and a second antenna coil on the main surface configured to communicate with an IC tag; and
an IC storage medium which stores data transmitted via the first and second antenna coils,
wherein,
the first antenna coil and second antenna coil are separated by a distance which prevents magnetic coupling between them,
the first antenna is configured to communicate over a wider range of frequencies than the second antenna, and
the second antenna is configured to communicate over a longer distance than the first antenna,
a metallic plate is bonded to the main surface of the substrate via a magnetic sheet; and
the second antenna coil is disposed between the magnetic sheet and the main surface of the substrate.
16. The portable communication terminal according to claim 15 , wherein the first and second antenna coils are disposed within a plane of the substrate, and one of antenna coils is disposed within an inner periphery of the other antenna coil.
17. The portable communication terminal according to claim 15 , wherein a central portion of the substrate is provided with a signal processing circuit including the IC storage medium.