A slot antenna positioned on a substrate includes a grounding portion, a radiating portion, and a feeding portion. The grounding portion is positioned on the substrate. The radiating portion is parallel to the grounding portion and shaped like an irregular octagon. The radiating portion includes an irregular slot that is defined substantially in the center of the irregular octagon. The feeding portion electrically connects the radiating portion to the grounding portion for feeding electromagnetic signals.
1. A slot antenna positioned on a substrate, comprising:
a grounding portion positioned on the substrate;
a radiating portion parallel to the grounding portion and shaped like an irregular octagon comprising an irregular slot being defined in substantially in the center of the irregular octagon, wherein the irregular slot is defined by a rectangular-shaped slot and an L-shaped slot communicating with one corner of the rectangular-shaped slot; and
a feeding portion electrically connecting the radiating portion to the grounding portion for feeding electromagnetic signals.
2. The slot antenna as recited in claim 1 , wherein another corner of the rectangular-shaped slot opposite to said one corner extends inward towards the L-shaped slot.
3. The slot antenna as recited in claim 1 , a joint consisting of the feeding portion and the radiating portion is positioned at a corner portion of the radiating portion close to the L-shaped slot.
4. The slot antenna as recited in claim 1 , further comprising a connecting portion connecting the grounding portion to the feeding portion.
5. The slot antenna as recited in claim 4 , wherein the feeding portion is cylindrically-shaped, and the connecting portion is hollow and cylindrically-shaped.
6. The slot antenna as recited in claim 5 , wherein the feeding portion and the connecting portion are tightly coupled together.
7. The slot antenna as recited in claim 6 , wherein the feeding portion and the connecting portion can easily be connected or disconnected.
8. The slot antenna as recited in claim 1 , wherein the grounding portion and the radiating portion are made of the same materials.
9. The slot antenna as recited in claim 8 , wherein the material of the grounding portion and the radiating portion are made of iron.