The Study On Detection Method Of Water Vapor On Boundary Layer Based On Multi-agent System

Water vapor in the atmosphere is an important part of the atmosphere.The distribution and change of water vapor content is very complex.It is the main driving force for weather and climate change and plays an important role in the formation and evolution of severe weather at small and medium scales.How to effectively and accurately obtain information on water vapor distribution is of special significance for weather forecasting,climate monitoring,and disaster prevention and mitigation.The conventional atmospheric vapor detection method is affected by the spatial and temporal resolution or detection accuracy,which limits the acquisition of high-temporal resolution and high-precision vapor information.Current water vapor monitoring systems have many shortcomings in terms of observation time and spatial resolution,equipment cost,network density,and monitoring accuracy.Aiming at the problems existing in the current water vapor monitoring system,a multi-agent system is used as a receiving end of an electromagnetic wave to construct a water vapor monitoring network by means of a fourth-generation mobile communication network that is currently widely used.The atmospheric refractive index is retrieved from electromagnetic carrier signals as an important supplement to the existing water vapor monitoring network.This paper proposes a multi-agent-based boundary layer vapor detection method,and conducts in-depth research on the key technologies of this detection method.The main work of the paper includes the following aspects.The feasibility of multi-agent method inversion of atmospheric refractive index was demonstrated.The study of the detection method using electromagnetic waves with a carrier frequency of 2.4 GHz emitted by a communication base station is essentially a study of the attenuation of electromagnetic waves in the propagation path of the boumdary layer in the lower atmosphere.Obviously,the attenuation is related to the atmospheric temperature,pressure,and humidity on the electromagnetic wave propagation path,that is,the water vapor content on the electromagnetic wave propagation path.According to the principle of retrieving the water vapor content in the atmosphere using the refractive:index of electromagnetic waves,a multi-agent system was designed.The system consists of an improved hierarchical network structure,and consists of three types of agents:sensor agent,management agent,and interface agent.A multi-agent system for water vapor detection was designed.The organizational structure and data transmission form of the multi-agent system are defined.The design and analysis of data acquisition algorithms for sensor agent in multi-intelligent systems were carried out.The feasibility of the multi-agent system to observe the water vapor at the boundary layer is demonstrated from three aspects:multi-agent system detection network technology requirements,single frequency synchronization network,and data transmission technology used in the fourth generation communication system.Systematic demonstration of inversion method and signal processing algorithm for retrieving the atmospheric refractive index N on the propagation path of electromagnetic waves based on the electromagnetic carrier signal received by the receiving end in the multi-agent boundary-layer water vapor detection method,and performing corresponding inversion experiments Verify the corresponding accuracy of different algorithls,analyze the problems and improvement methods of the three different algorithms.(l)Modulation signal autocorrelation function signal processing algorithm.The modulation signal autocorrelation function is used to calculate the propagation delay of the electromagnetic wave signal sent from the base station to the receiving end of the received carrier signal,and the electromagnetic signal carrier transmission pseudorange is calculated accordingly,and the atmospheric refractive index on the transmission path is inverted.(2)Carrier phase difference signal processing algorithm.Comparing the phase difference between the carrier signal received by the signal receiving end and the carrier signal generated syllchronously,the carrier pseudorange of the electromagnetic wave carrier signal is calculated according to the integer period fuzzy number and the phase difference,and the atmospheric refractive index on the transmission path is inverted.(3)Pilot signal tracking time positioning algorithm.The pilot signal tracking time positioning algorithm uses the OFDM transmission technology used in the fourth generation mobile communication system to accurately calculate the signal transmission delay,thereby accurately calculating the transmission pseudorange and inverting the atmospheric refractive index.Through the horizontal comparison and analysis of inversion results,in the same region,the same signal processing algorithm inverts the atmospheric refractive index under different weather conditions.A mathematical model was established to analyze the effect of different forms of water in the atmosphere on the inversion results of electromagnetic wave attenuation.The pilot signal tracking time positioning algorithm is used to perform observation experiments under different weather conditions.The experimental results verify the feasibility of the multi-agent method in retrieving the atmospheric refractive index,and the accuracy of the inversion result satisfies the demand for water vapor detection.The research in this paper proves that the multi-agent-based boundary layer vapor detection method is feasible and the inversion result is of high precision,which can be used as an effective supplement for the current vapor detection.