A novel technique for transferring data to biomedical implantable devices through the inductive power transfer link is presented. The new modulation technique presented in this paper is based on changing the duty cycle of the switching pulse of the class E power amplifier which drives the external coil. Hence, we call it duty cycle shift keying (DCSK). Inductive link efficiency and voltage gain are analyzed for the DCSK technique. Based on the mathematical analysis of the proposed technique its bit error rate is close to that of the BFSK. However, it can achieve a data rate to carrier frequency of 100 %. The modulator and demodulator of the proposed technique are simple and make it suitable for bio-implantable devices. The proposed circuit is simulated by advanced design system simulator using the 0.18 lm CMOS technology. Moreover, in order to verify the effectiveness of the proposed technique, a test setup is implemented using off-theshelf components. The simulation as well as measurement results will be provided in this article.

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