MUMBAI, India, July 24 -- Intellectual Property India has published a patent application (202641086517 A) filed by Ghali Venkata Subbarao; Banda Sai Sandeep; and Klef Deemed To Be University on July 15, 2026, for A Miniaturized System For Subsurface Defect Detection In Composite Materials Using Gaussian Windowed Logarithmic Frequency Modulated Thermal Wave Imaging.
Inventors include Ghali Venkata Subbarao; and Banda Sai Sandeep.
The application for the patent was published on July 17, 2026, under issue no. 29/2026.
Abstract: The present invention discloses a miniaturised system for subsurface defect detection in composite materials using Gaussian windowed logarithmic frequency modulated (LogFM) thermal wave imaging. The system integrates compact thermal excitation, infrared sensing, and embedded signal processing to enable portable, low-power, and real-time non-destructive evaluation. In the proposed method, a logarithmic frequency modulated thermal excitation is applied, wherein the excitation frequency varies exponentially with time to achieve uniform depth-wise probing consistent with thermal diffusion behavior. The thermal response is acquired using an infrared imaging system and processed to reveal subsurface anomalies. A key aspect of the invention is the application of Gaussian windowing in the frequency domain, which addresses inherent limitations of conventional LogFM such as spectral leakage, side lobe interference, and reduced pulse compression efficiency. Gaussian windowing enables effective side lobe suppression, concentrates energy in the main lobe, and significantly enhances signal-to-noise ratio (SNR), thereby improving defect detectability, depth resolution, and localization accuracy. The invention further emphasizes the implementation as a miniaturised system, which reduces size, power consumption, and system complexity while enabling real-time processing and field deployment. This compact architecture allows single-shot multi-depth inspection without repeated experiments, making it suitable for portable and embedded non-destructive testing applications. The proposed system provides enhanced detection of both shallow and deep defects in composite materials, metals, and multi-layer structures, with applications in aerospace, industrial inspection, and structural health monitoring.
Disclaimer: Curated by HT Syndication.
