Substance unmarked detection and identification method based on terahertz waves

Abstract

The invention provides a substance unmarked detection and identification method based on terahertz waves, and belongs to the technical field of substance detection, and the method comprises the steps:obtaining a reference signal and a plurality of groups of sample transmission signals, carrying out the discrete sampling of the reference signal and the plurality of groups of sample transmission signals, processing the reference signal, and obtaining the terahertz frequency spectrum of the reference signal; processing the transmission signal to obtain a terahertz frequency spectrum of the transmission signal; and comparing the terahertz frequency spectrum of the reference signal with the terahertz frequency spectrum of the transmission signal to obtain a terahertz absorption spectrum of thesample, and comparing the terahertz absorption spectrum with a terahertz fingerprint spectrum database to realize identification of the to-be-detected sample. According to the invention, the interference of Gaussian noise on signals is reduced, and sample terahertz characteristic spectrum detection identification is realized; compared with a traditional algorithm, characteristic absorption peaksare convenient to extract, the detection probability is high, the signal-to-noise ratio is high, the terahertz characteristic spectrum of the sample is extracted, sample detection and recognition areachieved through comparison of a terahertz fingerprint spectrum database, and the sample detection probability is superior to 90% and higher than the detection probability of the traditional algorithm.

Description

technical field [0001] The invention relates to the technical field of substance detection, in particular to a terahertz wave-based method for detecting and identifying substances without a mark. Background technique [0002] Terahertz waves are electromagnetic radiation between radio waves and light waves with a frequency range of 0.1THz to 10THz and a wavelength range of 30μm to 3mm. Photon energy, strong penetrability, high safety, good orientation, high bandwidth and other characteristics have great application value in national defense, homeland security, astronomy, medical, biology, computer, communication and other scientific fields. [0003] Most substances in nature have obvious responses in the terahertz frequency band, such as the vibration and rotational energy levels of many biological macromolecules, and the phonon vibration energy levels of semiconductors and superconducting materials are all in the terahertz frequency band; Polar materials have very strong p...

AI Technical Summary

Problems solved by technology

The above methods have defects such as difficulty in extracting characteristic absorption peaks, low detection probability, low signal-to-noise ratio, and poor reliability of test results, which cannot meet the application requirements of high-precision detection and identification of terahertz substances.

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