Implantable Pulse Generator Recharging With Adaptive LSK Communication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dynamic wireless power transfer systems for implantable pulse generators (IPGs) face challenges in maintaining reliable communication due to variability in resonant frequency and alignment issues, leading to reduced modulation depth and increased bit error rates, especially in static systems.
Innovation Solution
The IPG employs a recharging unit with capacitive load shift keying (C-LSK) and resistive load shift keying (R-LSK) for dynamic selection of communication modes based on measured parameters and information type, allowing for efficient and reliable communication by adapting modulation depth to charging conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If dynamic tuning methods are used to track resonant frequency, then communication reliability is improved, but device complexity increases due to sophisticated algorithms
Solution Approach 1:
The patent changes the operating frequency parameter dynamically to track the resonant frequency of the WPT system. The IPG adjusts its operating frequency based on measured parameters (such as impedance or current) to maintain optimal communication conditions despite misalignment between charger and IPG, thereby improving communication reliability without requiring complex search algorithms.
2Ease of operation
If charger and IPG are misaligned, then patient comfort is improved, but modulation depth decreases and communication performance is reduced
Solution Approach 1:
The patent implements dynamic frequency adjustment that automatically adapts to alignment conditions. The system continuously monitors operating parameters and adjusts the resonant frequency in real-time, allowing the IPG to maintain effective communication even when the charger is misaligned with the IPG, thus preserving both patient comfort and communication reliability.
3Device complexity
If amplitude modulation is used for communication, then communication simplicity is improved, but modulation depth variability increases under dynamic conditions
Solution Approach 1:
The patent employs feedback mechanisms where the IPG measures operating parameters (such as impedance, current, or voltage) and uses this information to adjust its operating frequency. This closed-loop control maintains optimal modulation depth by adapting to changing WPT system conditions, ensuring consistent communication performance while preserving the simplicity of amplitude modulation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach provides a highly efficient and reliable communication link, minimizing parasitic heating and ensuring patient safety, with reduced charger power source size and predictable charging sessions, while maintaining uninterrupted therapy delivery.
Implementation Method 1
a recharging unit with a rechargeable battery adapted to receive energy from a separate charger utilizing inductive or resonant magnetic power transfer from a primary coil of the charger to a secondary coil of the recharging unit
Implementation Method 2
utilizing inductive or resonant magnetic power transfer
Implementation Method 3
the recharging unit is adapted to communicate information from the IPG to the charger utilizing capacitive load shift keying (C-LSK) and resistive load shift keying (R-LSK), wherein C-LSK may purposefully add shunt capacitance to achieve detuning
Implementation Method 4
R-LSK may purposefully add a load (resistive or current sink)
Data Source
AI summary
An implantable pulse generator (IPG, 104) for neuro stimulation of a patient's body is described having a recharging unit (104.d) with a rechargeable battery (104.b) adapted to receive energy from a separate charger (110) utilizing inductive power transfer from a primary coil (110.a) of the charger to a secondary coil (117) of the recharging unit, wherein the IPG (104) further comprises a processing unit (104.e), wherein the recharging unit is adapted to communicate information from the IPG to the charger utilizing capacitive load shift keying (C-LSK) and resistive load shift keying (R-LSK). In order to improve communication reliability the processing unit is adapted to control dynamical selection of either C-LSK or R-LSK for communication of a pre-defined information and/or to control usage of both C-LSK and R-LSK for communication of a pre-defined information in a pre-defined sequence dependent on an actual measured value of at least one parameter of the electric circuitry of the recharging unit and/or dependent on the type of information which is to be communicated to the charger. Further, a system comprising the IPG and a charger is described as well as a neurostimulation device and a method for operating such IPG and such system.