The Research On Compatibility Analysis And Spectrum Efficient Utilization Technology For 5G Typical Candidate Bands

With the increasing requirements of different communication services,communication traffic has shown explosive growth,and communication technology is also evolving and updating continuously.Existing spectrum resources can not fully meet the requirements of current communication applications.In order to provide sufficient spectrum resources for the fifth generation(5G),we need to efficiently explore new spectrum resources and re-plan existing frequency resources of international mobile telecommunication(IMT)to make efficient use of limited spectrum.In view of the above problems,this dissertation studies the key technologies and issues in some typical candidate frequency bands of 5G,including suitability of each frequency band,radio wave propagation characteristics,multi-system electromagnetic compatibility method and solution,and spectrum efficient utilization technology.Moreover,a novel method for calculating spectrum utilization efficiency and power optimization methods are proposed to achieve the purpose of improving spectrum utilization efficiency.The main works and innovations can be summarized as follows:1.According to the latest resear-ch of international standardization organizations such as ITU and 3 GPP,and the deployment of actual services in different frequency bands in China,the potential candidate frequency bands for 5G in China are analyzed from the perspectives of the 2G/3G/4G frequency re-farming,and the utilization of new frequency band.In the frequency band below 6GHz,the feasibility of the existing2G/3G/4G spectrum re-farming and the labeled spectrum allocated for 5G is analyzed comprehensively.In the frequency band above 6GHz,the potential candidate frequency bands for 5G system in the range of6-100 GHz in China are proposed on the analysis of current frequency division,planning,allocation and utilization in China.2.According to the actual measurement results of typical 5G candidate frequency bands,this chapter analyzes the path loss model and shadow fading model of corresponding frequency bands respectively,and proposes the frequency dependence of the path loss parameters.Since MIMO is widely used in 5G,the actual 3D MIMO channel measurement is carried out in a typical urban micro-cellular deployment scenario under the conditions of 3.5GHz frequency and 100 MHz bandwidth.The vertical dimensional angles of each diameter are extracted from the measurement data and their statistical characteristics are analyzed.The performance of the 3D channel model with angular deviation is verified by the channel capacity index.3.In the performance analysis of electromagnetic compatibility among different radio systems in typical 5G candidate frequency bands,a compatibility analysis method of 5G and fixed-satellite service which is constrained by RF characteristics and broadband filter is proposed for3400-3600 MHz low frequency band.The isolation distance of the system is obtained by simulations and field testing.The space-time based compatibility analysis method of 5G and inter-satellite service is proposed for the frequency band of 26 GHz.The compatibility coexistence performance of 5G system and ISS is verified considering the actual urban population.4.Research on the method to calculate spectrum utilization efficiency based on actual tests.In this chapter,the IMT field strength is tested by fixed monitoring stations and mobile monitoring vehicles measurements.On the analysis of the spectrum usage in time,frequency and area domain,a novel time-frequency-space based spectrum utilization efficiency method is proposed in a non-cooperative sense.5.Research on efficient spectrum utilization technology for typical candidate frequency band of 5G.A power optimization scheme for heterogeneous cellular self-organizing network is designed by using mobile edge computing technology to improve network coverage and achieve efficient utilization of spectrum.In this paper,the software and hardware simulations are built to verify the performance.An adaptive boundary algorithm for the heterogeneous cellular networks is proposed to determine the covering boundary.After self-configuration and boundary determination,the power optimization of users covered by heterogeneous networks is realized according to the cost function based power adjustment scheme.