DEVELOPMENT OF BIO-IMPLANTED MICRO-SYSTEM WITH SELF-RECOVERY ASK DEMODULATOR FOR TRANSCUTANEOUS APPLICATIONS

作者：Mutashar Saad^*; Hannan M A; Samad S A; Hussain A

来源：Journal of Mechanics in Medicine and Biology, 2014, 14(4): 1450062.

DOI：10.1142/S0219519414500626

• ASK modulation
• class-E power amplifier
• inductive powering
• voltage regulator
• bio-implanted devices
• low frequency ISM band

This paper deals with the development of bio-implanted micro-system with low-power and high data rate based on amplitude shift keying (ASK) modulation technique to stimulate nerves and muscles. The modified system is operated by a low-frequency band 13.56MHz according to the industrial-scientific-medical (ISM) bands to avoid the biological tissue damage. The data rate on the demodulator side is from 1Mb/s and up to 1.5Mb/s depending of generating binary signal (T-BIT = 1 mu s or 0.5 mu s) with modulation index of 13% and modulation rate 7.3%, 9% and 11%, respectively. The proposed inductive coupling link achieves 73% of link efficiency. The modified rectifier with self-threshold voltage cancellation techniques and voltage regulator without thermal protection circuit and without passive elements occupies small area that is modified to generate adequate and stable DC voltages of 1.8V. A new ASK demodulator structure based on two comparators is developed to extract a synchronized demodulated signal with minimum error. Thereby no need for clock recovery circuit and delay-locked loops (DLL) circuits for data synchronization at 1Mb/s and 1.250Mb/s of speed. The system designed using OrCAD Pspice 16.2 is based on 0.35 mu m technologies.

• 出版日期2014-8