Research On Cooperative Transmission Based On 5G Hybrid Muli-Service

With the increase of data rate and network capacity,users have put forward higher requirements for service transmission in the Fifth Generation(5G).At the same time,the time-frequency resources of each unicast service occupied by the broadcast service will cause a waste of resources,so how to realize the parallel transmission of multiple services of broadcast,multicast and unicast has become a very important research topic.The rate splitting(RS)technology splits the information and transmits it after encoding,which provides a reference for the study of multi-service cooperative transmission.Based on hybrid multi-service cooperative transmission,this thesis mainly studies the following:First,the multi-service cooperative transmission scheme based on the RS idea is studied.The scheme splits unicast information into public information and private information.Public information and broadcast information form super public information,which is jointly encoded with unicast private information and transmitted to users.At the receiving end,the successive interference cancellation technology is used to decode the super public information first,then delete it after decoding,and then decode the private information.In order to realize the multi-service transmission in 5G,a hybrid precoding multi-service transmission scheme is proposed.Through simulation analysis,it is proved that the performance of the multi-service cooperative transmission scheme based on the RS idea is superior to the traditional multi-service cooperative transmission scheme.Second,the idea of dynamic segmentation of the antenna array is proposed,and a fixed beam coverage scheme is proposed based on this idea.When studying the application of the multi-service cooperative transmission scheme in the low-orbit satellite scenario,the beam formation of the entire antenna array will cause the link margin of the under-satellite users to be too large,while the edge users have no link margin.In order to solve this problem,the idea of dynamically dividing the antenna array is proposed,which the antenna array is divided into several sub-arrays unevenly,and then the power of the array is reasonably distributed.The beam formed by the small array covers users who are closer to the satellite.The beam formed by the big array covers users far away from the satellite.Based on this idea,under the condition of meeting the link budget,designing the angle of beam coverage,the number of beams,the size of the sub-array,etc.Third,applying the designed beam coverage scheme to the low-orbit satellite multi-service cooperative transmission scheme.A multi-service transmission scheme in the low-orbit satellite is proposed.In this process,analyzing the multi-service cooperative transmission based on RS technology in the low-orbit satellite and combing the beam coverage scheme with it.Finally,it is simulated to verify the performance of the multi-service cooperative transmission scheme.