Reconfigurable quarter-mode substrate integrated waveguide microwave microfluidic sensor

Abstract

The invention discloses a reconfigurable quarter-mode substrate integrated waveguide microwave microfluidic sensor. The top layer includes two units with the same structure, and each unit includes metal patches, microstrip lines and SMA connectors; the middle layer is a dielectric plate; the bottom layer includes metal sheets and grooved CSRR structures. The metal patch is a quarter-circle fan-shaped structure. In each quarter-circle fan-shaped structure, the field strength near the center of the two perpendicular right-angle sides is the strongest. For radiation, the CSRR is designed just below the two quarter-circle fan-shaped structures, and the PDMS with the microfluidic channel dug in advance is placed just below the CSRR, so that the electric field of radiation can pass through the PDMS to the greatest extent. liquid, thereby increasing the sensitivity of the sensor. The volume of liquid required to pass through the PDMS is small, which avoids waste of sample liquid and prevents environmental pollution.

Description

technical field [0001] The invention belongs to the field of microwave technology, and relates to a sensor excited by a microstrip line, in particular to a miniaturized microwave sensor based on a substrate integrated waveguide (SIW) for measuring the dielectric constant of an ethanol solution. Background technique [0002] Ethanol has a wide range of applications in pharmaceuticals, medical diagnostics, academia, and the beverage industry, where low-cost, miniaturized, potentially safe, and highly sensitive sensor devices operating at ambient temperatures must be available to accurately Analyze and monitor ethanol concentrations. Therefore, how to accurately and quickly measure the dielectric constant of liquids has become a hot topic of common concern in both academia and industry. [0003] In recent years, electrochemical sensors, as state-of-the-art sensors, have made outstanding contributions in detecting ethanol concentration. In this type of sensor, the resistance o...

AI Technical Summary

Problems solved by technology

However, they are difficult to integrate into miniaturized systems due to their bulky

[0004] Today's integration of microfluidic channels with radio frequency components opens up a very useful field where filling a microfluidic channel with a very small volume of liquid can affect the frequency and amplitude of the resonant frequency of the entire structure, However, as far as the microfluidic sensors currently used for microfluidic characterization are concerned, their sensitivity is often not high, and low sensitivity is likely to cause unnecessary errors in experiments.

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