1. Field of the Invention
The present invention relates to a dipole antenna, and in particular relates to a dipole antenna with reduced dimensions.
2. Description of the Related Art
FIG. 1a shows a conventional dipole antenna 1, comprising a first arm 10, a second arm 20, a signal line 31 and a ground line 32. The signal line 31 is electrically connected to the first arm 10. The ground line 32 is electrically connected to the second arm 20. The dipole antenna 1 transmits a wireless signal. The wireless signal has a wave length λ.
Conventionally, the lengths of the first arm 10 and the second arm 20 are λ/4. Thus, decreasing the dimensions of the conventional dipole antenna 1 is difficult. Also, with reference to FIG. 1b, conventional dipole antennas 1 have a housing 40, and the housing 40 covers the first arm 10, the second arm 20, the signal line 31 and the ground line 32. Thus, when the conventional dipole antenna 1 is disposed on a top edge of a portable computer (for example, a notebook computer), the appearance of the portable computer is influenced. Meanwhile, when the conventional dipole antenna 1 is disposed on a side edge of the portable computer, signal transmission thereof is deteriorated. Specifically, the circuit board of the portable computer interferes with electrical fields of the dipole antenna 1.