A Single-Frequency Multipath Effect Detection and Mitigation Method

Abstract

The invention provides a detecting and relieving method for a single-frequency multi-path effect. The method includes the steps that a receiver receives original data; the original data comprise a pseudo-range observation value and a carrier wave phase observation value; the pseudo-range observation value and the carrier wave phase observation value are combined, so that a biased pseudo-range / carrier wave phase observation value is obtained; the average value of pseudo-range / carrier wave phase observation values of multiple epochs is calculated to obtain the time sequence of an unbiased code reduction phase deviation combination observation value; a Fourier transformation method is adopted for analyzing and extracting frequency spectrum information of the time sequence of the unbiased code reduction phase deviation combination observation value; the frequency spectrum information is analyzed to obtain multi-path effect frequency distribution; multi-stage wavelet decomposition and wavelet reconstruction are performed on unbiased code reduction phase deviation combination observation value to obtain a multi-path effect estimated value; the difference between the pseudo-range observation value and the multi-path effect estimated value is solved to obtain a pseudo-range observation value after multi-path relieving. Influences of the multi-path effect are effectively reduced, and the quality of observation data is improved.

Description

technical field [0001] The invention belongs to the technical field of satellite navigation, and in particular relates to a single-frequency multi-path effect detection and mitigation method. Background technique [0002] As early as the development and demonstration stage of the GPS system in the 1970s, the influence of multipath effects on positioning was clearly put forward as one of the demonstration factors. The multipath effect refers to the reflection or diffraction signal caused by the surrounding environment in the received signal due to the influence of environmental factors during the transmission and propagation of the GPS satellite positioning signal. This signal distortion causes the polarization of the GPS signal The mode and delay change, resulting in positioning deviation and even signal loss of lock, which constitutes the multipath effect in satellite positioning. [0003] The multipath effect mainly has the following characteristics: (1) The multipath eff...

AI Technical Summary

Problems solved by technology

[0006] From the above content, it can be seen that when using hardware for multipath suppression, the influence of part of the multipath effect can be suppressed, but there are still some multipath effects that cannot be eliminated, so the multipath effect will still affect the data quality of GNSS observations

When using software for multipath suppression, most of the existing multipath effect processing methods are to extract the multipath effect from the residual error of the post-processing results, not the real multipath effect extraction, especially in real-time applications. The above methods have defects that are difficult to repair, and it is difficult to effectively alleviate the multipath effect and improve the data quality of GNSS observation data

Images