In-Band Wireless Charging Communication Using Golay Code Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless power transfer systems lack robust in-band communication methods to ensure reliable power control, status reporting, and foreign object detection, especially in scenarios with multiple devices of arbitrary orientation and position, which complicates communication between the Load and Source.
Innovation Solution
A wireless charging in-band communication system that uses channel encoding, biphase modulation, Golay complementary codes for synchronization, and impedance switching to facilitate reliable communication, incorporating a transmitter module for message formatting and a receiver module with impedance sensing and error correction capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If classic asynchronous serial communication interface is used for wireless power transfer communication, then device complexity is reduced, but communication reliability deteriorates due to lack of error protection and robust synchronization
Solution Approach 1:
The patent applies preliminary action by prepending synchronization sequences with Golay complementary codes before the actual message data. This pre-synchronization mechanism establishes reliable timing and phase reference before communication begins, improving communication reliability without requiring complex real-time synchronization algorithms during data transmission.
Solution Approach 2:
The patent implements beforehand cushioning through channel encoding with error correction and detection codes. This protective layer is added in advance to the message data, providing error protection that cushions against communication reliability deterioration caused by noise and interference in the wireless power transfer channel.
2Reliability
If impedance switching is used for in-band communication during wireless power transfer, then communication capability is improved, but power transfer efficiency deteriorates due to reflected impedance changes
Solution Approach 1:
The patent applies periodic action by using impedance switching that occurs in synchronized periods aligned with the wireless power transfer cycle. The impedance changes are timed to occur during specific phases of the power transfer, allowing communication signals to be modulated onto the power transfer medium while minimizing disruption to the overall power transfer efficiency through periodic, controlled impedance variations.
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 solution enables robust and efficient communication between the Load and Source, supporting multiple devices with arbitrary orientations, ensuring reliable power transfer and foreign object detection without the need for complex hardware or close proximity, thereby improving communication reliability and reducing errors.
Implementation Method 1
A modulation module performs biphase modulation for DC balanced signals and impedance switching to change reflected impedance seen by the source
Implementation Method 2
The receiver module includes an impedance sensing circuit to detect changes in the reflected impedance of the transmitter module
Implementation Method 3
A front end filter is provided that is used for pulse shaping and noise rejection
Implementation Method 4
A preamble detection block has a Golay complementary code correlator used for message detection, synchronization, and equalization coefficient estimation and selection
Data Source
AI summary
A wireless charging in-band communication system includes a channel encoding for message error correction and detection. A modulation module performs biphase modulation for DC balanced signals and impedance switching to change reflected impedance seen by the source. A synchronization module prepends the message with a synchronization sequence having Golay complementary codes. A receiver module receives the message from the transmitter module. A preamble detection block has a Golay complementary code correlator used for message detection, synchronization, and equalization coefficient estimation and selection. A decoding module that performs biphase demodulation with error correction with a DC offset being estimated as the average value of the signal over the length of the message before channel decoding. The decoding module performs equalization, error correction and detection channel decoding.