New CO2 Sensor with High Resolution and Fast Response

Abstract

The most common principles for CO2 sensors are only partially fulfilling the requirements of cardiovascular and respiratory applications. A new acoustic sensor principle is claimed to be favorable in several respects, such as size, resolution response time, reliability and cost. The sensor makes use of an electro acoustic element coupled to a Kundt resonator. The resonance frequency is determined by the mean molecular mass of the gas contained in the resonator, which may, in turn, be dominated by the variations of CO2 concentration. A phased locked loop (PLL) oscillator provides both voltage and frequency outputs of the sensor. In this paper, a prototype design is presented, along with experimental results demonstrating that resolution, linearity and response time adequate for biomedical applications may be achieved.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 25, 2001
Accession Number
ADA410459

Entities

People

  • B. Hoek
  • F. Granstedt
  • M. Ekstroem
  • U. Bjurman
  • Y. Baecklund

Organizations

  • Mälardalen University

Tags

Communities of Interest

  • Sensors

DTIC Thesaurus Topics

  • Accuracy
  • Acoustic Absorption
  • Acoustic Detectors
  • Acoustic Resonators
  • Acoustic Waves
  • Carbon Dioxide Sensors
  • Detectors
  • Electrical Impedance
  • Electronics
  • Environmental Monitoring
  • Frequency
  • Frequency Shift
  • High Resolution
  • Impedance
  • Reliability
  • Standards
  • Surface Acoustic Waves

Readers

  • Optical Fiber Sensing and Electromagnetic Propagation.
  • Radar Systems Engineering.
  • Software Engineering

Technology Areas

  • Biotechnology