A low energy pulse interval modulation for implantable devices

This paper presents a technique intended to reduce the power to transmit data, suitable for implanted biomedical wireless sensors. The signal acquired from an implantable sensor may receive some analog processing (filtering, amplification, linearization) and is AD converted for transmission. In low power applications, the conversion uses voltage to frequency converter (VFC). We propose an energy approach that consists of reducing the period that the transmitter remains on for VFC transmitters. It consists of a Pulse Interval Modulation - PIM signal. We have implemented the circuit on IBM 130nm CMOS technology and the simulations show the circuit can provide over 80% power savings.