Chemiresistive greenhouse gas proximal sensing system using miniaturized radar

Overview

This solution is a portable, chemiresistive proximal sensing system designed to detect and quantify greenhouse gases (GHG), including CO2 and methane, using a miniaturized radar sensor paired with a ZIF67 (Zeolitic Imidazolate Framework) gas-sensing film. By leveraging the strong correlation between gas concentration and changes in the film's electrical conductivity, the system translates radar signal energy variations into accurate GHG concentration readings. The platform offers a low-cost, field-deployable alternative to conventional gas detection instruments, with potential applications in agricultural emissions monitoring, environmental compliance, landfill and livestock facility assessment, and climate research.

Technical specifications

Key features:

• ZIF67 sensing film: Uniform pore size distribution enables high adsorption capacity for CO2 and methane, with conductivity that shifts significantly upon gas exposure.
• Silver paste conductors: Integrated into the film to amplify induced current captured by the proximal radar sensor.
• Miniaturized radar detection: Captures conductivity changes through radar signal energy variations, eliminating the need for bulky laboratory instrumentation.
• Validated performance: Linear correlation (R² = 0.97) between signal energy and GHG concentration; reproducible results confirmed through five repeated trials with ANOVA analysis (F > 0.94).
• Sensing range: Operational range of 410–1500 PPM with approximately 15 PPM error; maximum sensing range extends to 2600 PPM within 15 minutes of exposure.
• Rapid response: Validated results obtained within 50 seconds of gas exposure.
• Portability and cost: Total system cost under $500, with a compact form factor suitable for handheld or drone-mounted deployment.
• AI-enabled edge processing: Planned integration with Raspberry Pi devices for real-time radar signal processing and data transmission, supporting AIoT (Artificial Intelligence of Things) workflows.
• Drone compatibility: Portable design enables mounting on unmanned aerial vehicles to reduce labor intensity in large-scale field sensing.

Technology readiness level

The technology has been validated at the laboratory scale through controlled experiments confirming both the operational sensing range (400–1500 PPM) and the maximum sensing capability (2600 PPM). Reproducibility has been demonstrated across multiple trials. Future validation efforts are planned to assess robustness under real-world field conditions, including varying weather scenarios (rain, sun, strong wind), chamber versus open-air deployment, and different sensing distances. Integration with AI-enabled edge devices for real-time data processing and drone-based deployment is part of the next development phase. The current readiness level supports pilot-scale field trials and collaborative refinement toward commercial deployment.