The design of rhombic antenna with a band-reject characteristic

In this paper, the CPW-fed monopole antenna with various parameters were constructed and studied to demonstrate the proposed bandvvidth-enhancement technique and band-reject function. The broadband characteristic was obtained by adjusting the length and width of the notch on ground plane. The broadband antenna operates -10dB return loss bandwidth over 118% from 3.11 to 11.88GHz. Furthermore, embedded a straight slit close to quarter wavelength on one of the ground plane. It plays a role as a filter to eliminate the useless band 5.1 to 5.81GHz. This antenna has advantages of ease manufacture, good radiation characteristic, small size and omni-directional patterns.