Patent ID: 8294619

Claim:
An unsymmetrical dual-band antenna, comprising: a substrate having a first surface and a second surface opposite to the first surface; a first radiation unit disposed on the first surface of the substrate, wherein the first radiation unit comprises: a first radiation portion having a first length, wherein the first radiation portion is operated within a first band; and a second radiation portion having a second length, wherein the second radiation portion is operated within a second band, the second radiation portion is connected to the first radiation portion, the second length is larger than the first length, and the frequency of the first band is larger than that of the second band; a second radiation unit disposed on the first surface of the substrate and adjacent to the first radiation unit, wherein the second radiation unit comprises: a third radiation portion having a third length substantially identical to the second length, wherein the third radiation portion is operated within the first band and adjacent to the first radiation portion; and a fourth radiation portion having a fourth length substantially identical to the first length, wherein the fourth radiation portion is operated within the second band and adjacent to the second radiation portion, and the fourth radiation portion is connected to the third radiation portion; and an impedance matching unit for adjusting the impedance match of the unsymmetrical dual-band antenna, wherein the impedance matching unit is disposed on the second surface and comprises a first patch, a second patch, a third patch and a fourth patch, opposite to and electrically connected to the first radiation portion, the second radiation portion, the third radiation portion and the fourth radiation portion respectively, the first patch and the fourth patch have a first slit and a second slit respectively, the first patch and the second patch are electrically connected to a feeding point, and the third patch and the fourth patch are electrically connected to a ground point.