Efficient ASK Data and Power Transmission by the Class-E With a Switchable Tuned Network.

In this paper, we introduce a novel amplitude shift keying modulation technique, suitable for biomedical implants, which works by switching a class-E amplifier between two tuned modes of operation selected by the input data level. Using this technique, transmission of power and data could be accomplished with higher power transfer efficiency compared with the commonly used drain/collector amplitude modulation topology. We also present a practical design methodology covering details of the class-E power amplifier together with its inductive link and the proposed modulator circuit. This methodology can be further utilized in other applications like cochlear implants for which we will compare the performance of both topologies at the same operating conditions. Moreover, we implemented both topologies, and we made various physical measurements at the same inductive link and set-up conditions. Both theoretical and measurement results will justify the advantage of our proposed topology and its overall energy efficiency over a typical one (42% to 30%). Utilizing a carrier frequency of 10 MHz and a modulation index of 10%, our system is able to transmit data at a bit rate of 1 Mbps, while delivering 24-mW power at the nominal coil separation of 6 mm. [ABSTRACT FROM AUTHOR]