Analysis Of Pseudolite Signal Propagation Effect In Indoor Environment

In recent years,location-based services have developed rapidly,and indoor positioning technology required for indoor location services has become a research hotspot.The indoor environment cannot receive GNSS signals,and other positioning methods,such as Bluetooth,Wi Fi,RFID,and ultra wideband,have obvious disadvantages.Under this condition,pseudolite technology has become an indoor positioning technology with broad research prospects due to its advantages of high accuracy,easy indoor and outdoor switching compatible with GNSS signals.However,the current pseudolite technology faces problems such as signals being easily blocked,multipath effects,and time synchronization in indoor positioning,and its development is limited.The purpose of this paper is to improve the positioning performance of the indoor pseudolite system by analyzing the effects of pseudolite signal propagation in the indoor environment and studying the effect of the indoor environment on the pseudolite signal.The main contents are as follows:(1)Indoor channel simulation.Using ray tracing technology,study indoor channel fading through radio wave propagation simulation,construct indoor channel model,and analyze channel impact from parameters such as power attenuation and delay spread.Simulation results show that when the indoor environment is simple,large-scale fading follows a logarithmic distribution,while small-scale fading is closely related to the environment.(2)pseudolite signal analysis platform construction.Complete the entire process from the front-end RF signal reception to the back-end baseband signal processing,focusing on the processing of pseudolite signals by the capture and tracking modules;Integrate the classic methods for the analysis of navigation signal quality at home and abroad,apply it to pseudolite signals,and analyze and evaluate the actual received signal quality.The actual test shows that the platform can be used for pseudo-satellite signal quality evaluation.(3)Analysis of indoor pseudolite signal propagation.Analyze the geometric layout of pseudolites,and use the carrier-to-noise ratio and other observations as indicators to study the spatial distribution characteristics of pseudolite signals.Design experiments to artificially create phenomena such as non-line-of-sight and multipath,and study the effects of non-line-of-sight and multipath on pseudolite signals from the perspective of carrier-to-noise ratio and signal tracking loop.The experimental results show that the non-line-of-sight and multipath phenomena in the indoor environment will significantly affect the signal tracking loop performance and thus the indoor positioning accuracy.This paper studies the effect of pseudolite signal propagation in an indoor environment through a combination of simulation and actual testing.Designed a pseudolite signal analysis platform and innovatively used traditional navigation signal analysis methods to evaluate pseudo-satellite signal quality;The effects of indoor non-line-of-sight,multipath and other factors on pseudo-satellite signal baseband processing and positioning performance were studied;This paper analyzes the effect of pseudolite signal propagation in an indoor environment,which can be used to improve the overall performance of the pseudolite positioning system and has a positive effect on the promotion of pseudolite indoor positioning technology.