<p>A broadband implantable antenna is presented for the biomedical implantable system&nbsp;applications. The proposed antenna adopts a spiral monopole structure to realize the purpose of miniaturization size. The total size of the antenna including the biocompatible superstrates is 15 &times; 15 &times; 1.42 mm3 operating frequency at 402 MHz. The effects of some design parameters on performance of proposed antenna are discussed. The simulated and measured in skin-mimicking gel show that the broad bandwidths of 150 MHz (310&ndash;460 MHz) and 260 MHz (280&ndash;540 MHz) at return loss of 10 dB can be achieved covering the entire Medical Device Radiocommunications Service (MedRadio) and Industrial Scientific Medical (ISM, 433&ndash;438 MHz) bands, respectively. The broadband implantable antenna performs an omnidirectional pattern, showing a good candidate for biomedical implantable systems application.</p> <p>&nbsp;</p>