Miniature broadband wire antenna

A novel antenna composed of three monopoles is investigated first in this paper. In the frequency range 775 - 1910 MHz, the return loss is lower than -10 dB. Meanwhile the radiation patterns are omnidirectional. On this basis, bending top, fractal, coplanar, and loaded structures are applied to realize the miniaturization. Finally, the dimension and performance of the antennas are compared. The results demonstrate that the above-mentioned structures can realize the dimension miniaturization as well as maintain the electrical properties. The frequency range of the antennas proposed in this paper includes all the CDMA and GSM-band network frequency and realizes "one-antenna, two-network, and four-frequency". Therefore they can be applied to mobile telecommunications terminal equipment.