Accumulated snow depth extraction method based on multi-system GNSS reflection signals

Abstract

The invention relates to the technical field of GNSS remote sensing, in particular to an accumulated snow depth extraction method based on multi-system GNSS reflected signals, which comprises the following steps: S1, calculating an elevation angle and a signal-to-noise ratio; s2, obtaining an original reflection signal of each satellite; s3, adaptively decomposing into a plurality of singular spectrum components with different frequencies; s4, determining a frequency range of a snow surface reflection signal; s5, retaining singular spectrum components of which the frequency range is overlapped with the target frequency; s6, carrying out LSP spectrum analysis; and S7, obtaining a snow depth calculation result. The method comprises the following steps: removing a direct signal part in a signal-to-noise ratio by using a low-order polynomial to obtain a reflected signal component; an original reflection signal is adaptively decomposed into a plurality of singular spectrum components with different frequencies by singular spectrum decomposition, and the singular spectrum components with corresponding frequencies are selected and recombined into a new reflection signal, so that the influence of noise and other reflectors around an observation station on snow surface reflection height calculation is weakened, and the snow depth extraction precision and reliability are ensured.

Description

technical field [0001] The invention relates to the technical field of GNSS remote sensing, in particular to a snow depth extraction method based on multi-system GNSS reflection signals. Background technique [0002] As an important environmental parameter, snow depth plays an important role in climate change, water resource utilization, and disaster prediction. However, traditional snow depth monitoring methods are relatively limited in time and space. The Global Navigation and Positioning system (GNSS) reflection measurement technology is only based on the geodesic GNSS receiver, and calculates the height of the reflection surface by analyzing the frequency change of the signal-to-noise ratio of the reflection signal, thereby obtaining the snow depth. 24 / 7, continuous advantage. The signal-to-noise ratio data used in GNSS reflection measurement is particularly susceptible to noise, and noise of different frequencies will be reflected in the signal-to-noise ratio data. I...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is: using a low-order polynomial to remove the direct signal part in the signal-to-noise ratio to obtain the reflected signal component; using singular spectrum decomposition to adaptively decompose the original reflected signal of each satellite in the GNSS system into several singular spectra of different frequencies According to the empirical range of snow depth, select the singular spectral component of the corresponding frequency to recombine into a new reflection signal, thereby weakening the influence of noise and other reflectors around the station on the calculation of snow surface reflection height, and ensuring the snow depth extraction of GNSS reflection signals Precision and Reliability

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