Research On Spatial Reuse Scheduling Algoriithm Of Millimeter Wave Communication Systems

With the rapid development of modern communication industry,the requirement of data rate for wireless multimedia applications such as uncompressed high definition video trans-mission and massive downloading are increasing faster and faster.The microwave frequency spectrum resource shortage capacity is limited,and further improving spectrum efficiency is difficult,therefore,it is not easy to achieve the requirement of high speed communication,that makes the high frequency communication become popular.The 30?300 GHz millimeter wave bands,which is not exploited and utilized sufficiently,are the most promising and ideal car-rier frequency candidate for the next generation of ultra-high-speed wireless communications.Recently,many countries have released their frequency band from 57 GHz to 66 GHz,the bandwidth of 9 GHz provides unlimited possibility of achieving ultra-high-speed wireless com-munications,which has attracted attention of academic and industrial researchers.The dense indoor WPANs,as the main application of millimeter wave scenario,needs to support the multi-link communication,however,the spectrum division includes only 2 channels are available in most of countries,hence,improving spatial sharing is the key problem of enlarging network capacity.In this dissertation,the beam training and spatial sharing technologies in millimeter wave wireless communications are studied.First of all,we investigate the beam training mech-anism in IEEE 802.11 ad and propose an improved beam training scheme based on the feedback of information.In the proposed scheme,the sender and the receiver will upload beam training result to the PCP/AP after beam training,then,the PCP/AP will generate the location-indexed beam information adapter table.PCP/AP will update the information of table periodically to keep the real-time reliability.With this information,on one hand,PCP/AP can effectively allo-cate the communication resources,and then the resources optimization scheduling is completed and the spatial reuse can be supported.On the other hand,data transmission at the same loca-tion will directly call the beamforming information from the table rather than initiating another beam training.The system can save resources and improve the efficiency of communications according to the above way.Secondly,a spatial reuse scheduling strategy based on the pro-tocol interference model is proposed.In this scheme,spatial reuse assessment criteria and the scheme of information collection are defined according to specific system model.The infor-mation from the adapter table is transformed into beam difference information according to the proposed beam training mechanism.The transferred table is used to judge whether these links could coexist with each other.Thus,the selected links are assigned to the corresponding service period,and data trans-mission scheduling scheme is generated according to the scheduling scheme of special reuse.Simulation results show that compared with the traditional spatial reuse technology,the pro-posed scheme can effectively improve the spatial multiplexing gain.Finally,we analyze the limitations of the protocol interference model,physical interference model based spatial reuse scheduling mechanism is studied,and then a novel spatial reuse scheduling strategy is proposed.In this scheme,the spatial reuse criteria can be defined by SINR,and in four different scenarios,a simpler judging expression form is deduced.The link equality has been taken into account after considering the scheduling scheme,the firstly requiring link is arranged to the service pe-riod preferentially,and then,the link will achieve spatial reuse,moreover,the resources in SP are utilized sufficiently.Simulation results show that compared with the traditional spatial mul-tiplexing technology,the proposed spatial multiplexing scheme based on physical interference model can further improve the spatial reuse gain.