Font Size: a A A

Spectrum Resource Allocation Method Of Massive Machine Type Communication

Posted on:2021-02-20Degree:MasterType:Thesis
Country:ChinaCandidate:W J HouFull Text:PDF
GTID:2428330629951242Subject:Information and Communication Engineering
Abstract/Summary:PDF Full Text Request
The next generation of wireless systems is expected to provide ubiquitous connectivity for traditional user equipment as well as mass machine type communication equipment.However,the massive increase in the number of wireless devices,the growing quality of service requirements of advanced multimedia,and the limitations of wireless network resources have put increasing pressure on the inherent radio spectrum allocation methods used in current access technologies.To some extent,the shortage of spectrum resources can be seen as a result of poor spectrum resource management policies,not just the physical shortage of spectrum.Based on the above-mentioned problems in spectrum resource management,considering that most literatures use subcarrier allocation methods to improve system throughput or reduce bit error rate,but do not involve the number of users supported,we propose an interference-aware subcarrier allocation algorithm(IASA);Considering the fact that cumulative interference is rarely considered in spectrum matching,this paper proposes a spectrum matching algorithm(SMIH)based on interference hypergraphs.First,the article describes the research background and significance of the topic of spectrum allocation in large-scale machine communication,and the current status of research at home and abroad.The related theories and methods involved in the two algorithms proposed in this paper are introduced,and the spectrum allocation methods in D2 D communication,as well as the methods of establishing interference maps and interference hypermaps are summarized,providing theoretical support for subsequent chapters.Secondly,we introduce the IASA algorithm in detail.Aiming at the problem of subcarrier allocation for D2 D communication in mMTC scenarios,a subcarrier allocation algorithm for mMTC interference perception is proposed.First,a system model for maximizing the number of mMTC accesses is established,and the maximum interference that each subcarrier can withstand is calculated.Then,determine the mMTC pair with the least interference to the subcarriers,and judge the access attribute according to whether the QoS requirements of the mMTC pair are met.When the cumulative interference caused by an mMTC pair is greater than the maximum interference that a subcarrier can withstand,the subcarrier will prohibit access by other mMTC pairs.Simulation shows that the performance of the IASA algorithm is significantly superior to the two comparison algorithms,which significantly improves the utilization of the uplink spectrum.At the same time,simulation results prove the effectiveness of the proposed subcarrier allocation algorithm(IASA),and provide an effective solution for the application of the Internet of Things.Then,we introduced the SMIH algorithm in detail.Aiming at the situation that the traditional interference graph does not take the cumulative interference into account,an interference hypergraph is proposed to describe the interference relationship between users and to match the channel with the user.In the matching process,a market model consisting of users and channels is first established,and the bid-sell relationship in the market is used to describe the matching relationship between users and channels.Then,among the matching algorithms,the search algorithm(MWIS)for the largest independent set of weights in the hypergraph is given firstly.Before each spectrum matching,find the set of points with the largest weight value without mutual interference in the hypergraph.Then,a hypergraph-based spectrum matching algorithm(SMIH)is proposed to match channels with users.Finally,simulation experiments were performed.The simulation results show that the proposed SMIH algorithm is feasible.Although the performance is lower than that of the graph-based spectrum matching algorithm,it is considered that the cumulative interference in the system is more in line with the actual communication scenario.The performance degradation is within an acceptable range.Finally,we summarize the main innovations proposed in this paper,and analyze the further related work that the proposed algorithm can carry out and clarify the next work.The thesis has 23 figures,5 tables and 77 references.
Keywords/Search Tags:mMTC, spectrum allocation, interference-aware, D2D communication, spectrum matching
PDF Full Text Request
Related items