This paper presents a CPW-fed, UWB-extended bandwidth, dual band-notched on-chip antenna with its equivalent circuit model. The UWB-extended bandwidth is realized by truncating the bottom corners of a rectangular patch radiator while a 90 • -rotated 'C'-shaped slot in the patch and a 'U'-shaped slot in the feedline are used to achieve two notch bands for mitigating the signal interference in the frequency bands of 5.15 to 5.925 GHz and 7.9 to 8.8 GHz. Based on the fundamental theory, different parasitic as well as distributed circuit parameters associated with the designed on-chip antenna are extracted, and then the corresponding equivalent circuit model is configured from them. The resultant circuit is validated with the well approved full-wave electromagnetic simulation result and is found in close approximation with each other.