An antenna module includes first, second, and third conductor arms. The second conductor arm has first and second end portions, and is coupled to an end portion of the first conductor arm to form a substantially T-shaped connection. The third conductor arm is spaced apart from the first and second conductor arms by first and second gaps, respectively, and is disposed parallel to the first conductor arm. The first end portion of the second conductor arm and the third conductor arm are electrically coupled to a coaxial cable for receiving two signals therefrom, respectively. The second end portion of the second conductor arm is electrically coupled to a ground cable for grounding.