Electronic device
An electronic device includes a signal processor, a substrate, and a conductive housing. The signal processor includes an oscillator that outputs oscillation signal. The substrate has a ground component, the signal processor being disposed on the substrate. The conductive housing is connected to a first site of the ground component and to a second site that is different from the first site. The first site and the second site being disposed at positions where a first area of the housing in which an impedance is higher than a first threshold due to the first site overlaps at least part of a second area of the housing in which an impedance is lower than a second threshold due to the second site.
1. An electronic device comprising:
a signal processor including an oscillator that outputs oscillation signal;
a substrate having a ground component, the signal processor being disposed on the substrate; and
a conductive housing connected to a first site of the ground component and to a second site that is different from the first site,
the first site and the second site being disposed at positions where a first area of the housing in which an impedance is higher than a first threshold due to the first site overlaps at least part of a second area of the housing in which an impedance is lower than a second threshold due to the second site.
2. The electronic device according to claim 1 , wherein
the first area is an area in the housing that is an odd-numbered multiple of ¼ wavelength of the oscillation signal away from the first site.
3. The electronic device according to claim 1 , wherein
the second site is located at the ground component, and
the second area is in a position in the housing that is an even-numbered multiple of ¼ wavelength of the oscillation signal away from the second site.
4. The electronic device according to claim 1 , wherein
the second site is located outside the ground component, and
the second area is in a position in the housing that is an odd-numbered multiple of ¼ wavelength of the oscillation signal away from the second site.
5. The electronic device according to claim 1 , wherein
the housing is connected to a third site that is different form the first site of the ground component and the second site,
the housing has a third area in which an impedance is higher than the first threshold due to the third site,
the first area and the third area overlap at two points, and a distance X between the two points satisfies the following condition:
0< X≤λ/ 10
where λ represents a wavelength of the oscillation signal, and
the two points are located within a circle with a radius of λ/20, centered at a point in the second area of the housing.
6. The electronic device according to claim 1 , wherein
the housing has a rectangular upper part and side parts that extend from edges of the upper part and are perpendicular to the upper part,
the first site is disposed on a side part extending from a short edge of the upper part, and
the second site is disposed on a side part extending from a long edge of the upper part.
7. The electronic device according to claim 1 , wherein
the first area and the second area each include a plurality of areas.
8. The electronic device according to claim 1 , wherein
the first site and the second site each include a plurality of sites, and
the number of sites of the second site is equal to or less than the number of sites of the first sites.
9. The electronic device according to claim 8 , wherein
the first site includes at least two sites, and
the second site includes one second area overlapping at least two first areas.
10. The electronic device according to claim 1 , wherein
the second site is disposed at a specific position on the substrate that is separated from the housing by an extension line connected to the housing.
11. The electronic device according to claim 10 , wherein
the housing is disposed in a specific area of the substrate, and
the second site is disposed in the specific area.
12. The electronic device according to claim 11 , wherein
the extension line is a wire disposed on the substrate.
13. The electronic device according to claim 1 , wherein
the first area or the second area includes an area according to a range of variation of a wavelength of the oscillation signal.
14. The electronic device according to claim 1 , further comprising
a connector to which a signal cable is connected and that is provided to the housing,
the first area being located near the connector.
15. The electronic device according to claim 1 , wherein
the first site includes a first specific first site and a second specific first site,
the first area includes a first specific first area in which an impedance is higher than the first threshold due to the first specific first site and a second specific first area in which an impedance is higher than the first threshold due to the second specific first site, the first specific first area and the second specific first area overlapping at two overlapping points, and
the first specific first site and the second specific first site are disposed at positions where a distance between the two overlapping points of the first specific first area and the second specific first area is at or under a specific threshold.
16. An electronic device comprising:
a signal processor including an oscillator that outputs oscillation signal;
a substrate having a ground component, the signal processor being disposed on the substrate; and
a conductive housing connected to a first site of the ground component and to a second site that is different from the first site,
the first site and the second site being disposed at positions where a distance between two overlapping points in a first area of the housing in which an impedance is higher than a first threshold due to the first site and a second area of the housing in which an impedance is higher than the first threshold due to the second site, is at or under a specific threshold.
17. The electronic device according to claim 16 , wherein
the first area is located in an area of the housing that is an odd-numbered multiple of ¼ wavelength of the oscillation signal away from the first site.
18. The electronic device according to claim 16 , wherein
the second site is located at the ground component, and
the second area is located in an area of the housing that is an odd-numbered multiple of ¼ the wavelength of the oscillation signal away from the second site.
19. The electronic device according to claim 16 , wherein
the second site is located outside the ground component, and
the second area is located in an area of the housing that is an even-numbered multiple of ¼ the wavelength of the oscillation signal away from the second site.
20. The electronic device according to claim 16 , wherein
the specific threshold is λ/10 where X represents the wavelength of the oscillation signal.