Loading...

System and Circuit Design for High Performance Wireless Power and Data Transfer for Biomedical Implants

Razavi Haeri, Ali Asghar | 2023

0 Viewed
  1. Type of Document: Ph.D. Dissertation
  2. Language: Farsi
  3. Document No: 58056 (05)
  4. University: Sharif University of Technology
  5. Department: Electrical Engineering
  6. Advisor(s): Fotowat Ahmadi, Ali; Ghasem Safarian, Amin
  7. Abstract:
  8. Wireless Power and Data Transfer (WPDT) is a major part of a biomedical implant system. Maximiazing the Power Transfer Efficiency (PTE) and maximizing the data rate are the main challenges in WPDT. In a conventional biomedical implant system, a single inductive link is used to transfer both power and data from outside the body to inside. Data is transmitted by modulating one of the carrier signal properties, i.e., amplitude, frequency or phase. While being simple and robust, this method suffers from the fundamental trade-off between the PTE and data rate. To address this issue, various methods have been proposed including multiple carriers and multiple inductive links, and inductive link plus antenna. These methods break the trade-off between PTE and data rate. However, complexity and the interference problem limits their use in a commercial biomedical implant system. In this thesis, we reconsider the fundamental trade-off between PTE and the data rate. We show that the actual performance limits of the single inductive link system have not been achieved by the published works. We use Frequency Shift keying (FSK) signal in a cycle-by-cycle manner and with a very low modulation index to maximize the data rate while maintaining a high power transfer efficiency. In addition, we propose a FSK demodulator with both high speed and high sensitivity. To validate the proposed method, a prototype chip was fabricated in 180nm CMOS process.According to measurement results, the proposed FSK demodulator is able to demodulate a FSK signal with 2.5% modulation index in a single cycle. Using this demodulator, a data rate of 5Mbps is achieved using a 5MHz carrier. The measured Bit Error Rate is 1.24  10-5 in 2.5% modulation index. In addition to the proposed method for optimization of the WPDT system performance, we proposed some methods to enhance the efficiency of the power amplifer outside the body
  9. Keywords:
  10. Frequency Demodulator ; Wireless Power and Data Transfer ; Inductive Link ; Biomedical Implants ; Frequency Shift keying (FSK)Demodulator ; System Design ; Bit Error Rate

 Digital Object List

 Bookmark

No TOC