Research On System Model And Performance Of Millimeter Wave Hybrid Satellite Terrestrial Network

The rapid development of 5G networks has greatly promoted the rapid development of the Internet of Things(IoT).Nowadays,IoT has covered many fields such as agriculture,industry,transportation,and military.This makes it possible to build smart cities and realize the interconnection of all things.In order to solve the problem of wide distribution and large number of IoT nodes,this paper adopts the structure of integrating satellite communication systems into terrestrial networks to form a Hybrid Satellite-Terrestrial Relay Networks(HSTRN).Meanwhile considering the development of various multimedia applications,it is essential to provide more bandwidth and improve system spectral efficiency.In this paper,the millimeter wave(mmWave)band and the Non-orthogonal multiple access(NOMA)transmission mechanism are introduced into the HSTRN,and then we propose a novel NOMA-based mmWave HSTRN.We provide a complete analytical framework of system performance under the multi-relay multi-user scenario.And we derive closed-form expressions of corresponding system performance.Considering the future demand for system throughput and spectrum efficiency of IoT,we first analyze the feasibility of the NOMA-based mmWave HSTRN.We analyze the character of mmWave and the transmission mode of the signal under NOMA transmission mechanism.From the single-relay single-user scenarios,we propose the system model and extend it to multi-relay multi-user scenarios.Meanwhile,we introduce the typical transmission technologies involved in HSTRN in detail,such as relay forwarding mode and node selection strategy.It provides the basic knowledge of the research and analysis of subsequent chapters.Then we analyze the key performance indicators of single-relay single-user mmWave HSTRN system.Rain attenuation is the main factor affecting mmWave links.We innovatively combine the multidimensional rain attenuation model with the statistical model and propose mmWave rain fading channel.And we analyze the outage probability and the ergodic capacity,and derive the corresponding closed-form expressions.Then we utilize Monte Carlo simulations to confirm the validity of our analytical results.From the results,it can be clearly seen that the proposed closed-form expression can evaluate outage probability(OP)and ergodic capacity of the system and the affect of rain attenuation on system performance is obtained.It provides a theoretical basis for further analysis of the system performance of multi-relay multi-user mmWave HSTRN.Based on the above research,we propose a novel relay selection strategy basedon opportunistic user scheduling by utilizing expected rain attenuation value.And we derive the closed-form expression of OP.Meanwhile,simulation results verify that the proposed strategy can significantly improve the performance and reduce the system overhead for relay selection.Then we introduce NOMA and design NOMA-based multi-relay multi-user HSTRN system.We provide the complete process of signal transmission and compare the system performance with OMA.The analysis shows that NOMA outperforms OMA in ergodic capacity and the proposed relay selection scheme improve the system performance and reduce the complexity.In summary,the mmWave and HSTRN into HSTRN system can effectively improve the reliability.We propose complete analysis framework of the NOMA-based mmWave HSTRN system and it shows theoretical guiding significance for the future construction of HSTRN.