ANSYS Wireless Power Implant — Biomedical Instrumentation & Clinical Sensing

Abstract — ANSYS Wireless Power Implant

Ansys Wireless Power Implant: Biomedical Engineering, Medical Electronics & Bio-Signal Modeling Integrated Clinical Investigation: Bio-Sensors · Analog Front-Ends (AFE) · Diagnostic Waveforms · DSP Algorithms · ~13630 Words Chapter 1: Electrophysiological Foundations, Action Potentials & Clinical Significance In the context of implantable bioelectronics, this work provides new insights into maximizing biomedical wireless power transfer (BWPT) via the systematic development of inductive links. This approach addresses the specific challenges of power transfer efficiency (PTE) optimization within the spatial/area constraints of bio-implants embedded in tissue. Key contributions include the derivation of an optimal self-inductance with S-parameter-based analyses leading to the co-design of planar spiral coils and L-section impedance matching networks. To validate the proposed design methodology, two coil prototypes— one symmetric (type-1) and one asymmetric (type-2)— were fabricated and tested for PTE in pork tissue. Targeting a 20 MHz design frequency, the type-1 coil demonstrated a state-of-the-art PTE of ∼ \sim 4% (channel length = 15 mm) with a return loss (RL) > > 20 dB on both the input and output sides, within an area constraint of < < 18 × \times 18 mm 2 . In contrast, the type-2 coil achieved a PTE of ∼ \sim 2% with an RL > > 15 dB, for a smaller receiving coil area of < < 5x5 mm 2 for the same tissue environment. To complement the coils, we demonstrate a 65 nm test chip with an integrated energy harvester, which includes a 30-stage rectifier and low-dropout regulator (LDO), producing a stable ∼ \sim 1V DC output within tissue medium, matching theoretical predictions and simulations. Furthermore, we provide a robust and comprehensive guideline for advancing efficient inductive links for various BWPT applications, with shared resources in GitHub available for utilization by the broader community.

Sensor Interfacing & Analog Front-End Conditioning

Advancements in bioelectronics have profoundly transformed contemporary implantable medical devices (IMDs), paving the way for enhanced management of chronic diseases and optimized surgical interventions . For example, neurostimulators [ 2 , 3 ] , pacemakers , retinal implants , spinal cord stimulators , and cochlear implants are some of the notable IMDs that have garnered considerable attention by providing targeted treatments. However, despite the splendid benefits offered to patients, powering these IMDs effectively continues to be one of the major challenges within the biomedical circuits and system design community. Traditional percutaneous wiring methods provide a consistent power supply, but they are vulnerable to damage due to material incompatibility and scarring at the tissue interface, and maintaining sterility for these devices is an extra challenge . Similarly, internal power sources, like batteries, occupy substantial space and must be surgically replaced at regular intervals due to their limited charge capacity and recharge cycles . Additionally, fluctuations in temperature and power consumption can lead to overheating, explosion, or chemical leakage. Recognizing these stringent limitations within the tissue environment, wireless power transfer (WPT) systems have emerged as key enablers for the progress of next-generation biomedical implants [ 10 , 11 , 12 , 13 ] .

Bio-Signal Waveform Analysis & Simulation Findings

Today’s biomedical WPT (BWPT) for implantable applications encompass resonant inductive [ 14 , 15 ] , capacitive , ultrasonic , optical , magnetoelectric [ 19 , 20 ] , and radio frequency based electromagnetic transmission modalities. Accordingly, numerous studies have addressed the specific requirements of IMDs based on these diverse WPT systems characterized by power transfer efficiency (PTE), power delivered to the load (PDL), device form factor (FF), surgical comfort (SC), tissue absorption (TA) and misalignment tolerance (MT) [ 22 , 1 ] . These parameters help to identify the pros and cons of the aforesaid untethered powering technologies as highlighted in Fig. 1 . Though another WPT method recognized as body-coupled powering (BCP) seems promising, it is still at the early exploration stage [ 23 , 24 , 6 , 25 ] , contrary to body-coupled communication which has been explored in detail over the last decade by multiple groups including our own [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ] . While multiple WPT options are prevalent, non-radiative inductive coupling (NRIC) based on resonant inductive WPT is considered the paragon among all as it is widely deployed in various IMD scenarios due to its size, scalable power range, superior short-distance power transmission performance, and tissue safety . A general block diagram of the NRIC link is depicted in Fig. 2 (a) , which is the prime focus of this work.

Scope & Clinical Applications

• Real-time multi-parameter vital signs telemetry (ECG, Heart Rate, SpO2, Temperature, Respiration)
• Low-noise Analog Front-End (AFE) conditioning with active Driven Right Leg (DRL) 50 Hz cancellation
• Digital signal processing in MATLAB: Pan-Tompkins QRS detection, FIR/IIR notch, and Continuous Wavelet Transforms
• Finite element tissue bio-electromagnetics and orthopedic mechanical simulations in COMSOL & ANSYS
• Complete Arduino firmware .INO sketches, circuit schematics, and university dissertation reports