A compact monopole antenna possessing triple resonance ($f_1$, $f_2$, $f_3$) characteristics for (USB) dongle applications is presented. The resonance characteristic $f_1$ is determined by the overall length of the antenna. The monopole antenna acts as the main radiator for $f_3$ as well as the coupling feeding structure for the parasitic resonators in $f_1$, $f_2$. The resonance characteristic $f_2$ is achieved by a combination of the capacitance formed by the coupling between the top and bottom parasitic substrate resonators and the inductance generated by a via bridging the two parasitic resonators.