分层无线网络中的切换和接纳控制研究
|
摘要
随着移动互联网的不断发展,用户通过移动通信网络接入到互联网的需求日益增加,出现了大量需要高质量服务的无线多媒体业务。这使得移动通信系统的数据流量呈现爆发式增长,需要无线网络提供有效的支持,给移动通信系统的发展带来了巨大的挑战。据统计,大约90%的移动数据业务发生在室内,为这些业务提供良好的室内覆盖显然非常重要。为了解决严重的室内覆盖问题,人们提出利用家庭基站来为室内或者小区域内用户提供高质量服务,改善网络容量。
下一代的无线通信系统中引入家庭基站以后,改变了传统的网络结构,出现了宏基站/家庭基站分层网络。宏基站与家庭基站重叠覆盖,二者在应用场景、覆盖范围、网络容量、业务支持能力和发射功率等方面都存在较大差异,相互补充,共同为无线用户提供高质量服务。由于这种差异性,使得传统的无线资源管理技术不能直接应用于分层网络。无线资源管理是实现分层网络性能优化的关键。一方面,分层网络的重叠覆盖场景使得业务的切换更加复杂,尤其是在存在大量家庭基站的情况下,如何在提高用户体验的同时,减少频繁和不必要切换是分层网络切换算法研究的重点；另一方面,多样化的业务需求与有限的无线带宽资源之间存在矛盾,需要根据宏基站与家庭基站各自的技术特点,在保证一定服务质量的同时,针对不同业务进行接纳控制,提高无线资源的利用率。
本文研究内容集中在分层网络无线资源管理中的切换和接纳控制技术,进行如下几个方面的研究：
用户在部署有多个家庭基站的分层网络内运动,为了获得更高的传输速率,可能会在各小区之间进行频繁的切换,严重增加了网络的负载,切换决策需要在用户满意度与网络性能之间实现平衡。首先分析了场景中影响切换决策的几个因素,考虑了非实时性数据业务到达的突发性,然后将该场景的切换问题建模成马尔可夫决策过程模型,数据效用函数表示用户在候选网络中业务传输数据量,信令开销函数表示切换给网络带来的负载,选择切换到效用最大的目标网络。仿真结果表明了提出的切换方案与传方法相比有最大的效用。
用户的数据业务在家庭基站内的网络连接时间受到该用户的移动性、业务数据量、业务到达以及可用带宽的共同影响,网络在进行接纳决策时无法获得完整信息。针对该问题,首先给出了路径和速度的用户运动模型,根据对用户历史位置信息的观测对用户进行移动预测；然后分析了四类突发的数据业务到达事件,这四类事件将对网络产生不同的信令开销;最后利用部分可观测的马尔可夫决策过程理论,给出观测空间以及观测函数。仿真结果证明了提出的接纳控制方案有效提高了家庭基站的资源利用率。
分层网络中各小区存在各种切换业务以及新到达业务,针对现有的接纳控制方案中存在家庭基站资源利用率不高的问题,提出在传统接纳控制方案的基础上进行业务转移。当家庭基站中有空闲资源时,可以选择将连接到宏基站而处在家庭基站覆盖范围的业务切换到家庭基站。将上述问题用半马尔可夫决策过程理论建模,定义了网络的能量效用函数。仿真结果表明提出的能效优先的业务接纳和转移策略在获得最大效用的基础上,有效提高了家庭基站的资源利用率,降低了业务的阻塞率和掉话率。
With the rapid development of mobile Internet, the demand for accessing to the Internet via mobile communication network by users is increasing. Various types of wireless multimedia services requiring high quality service emerge, which promotes the explosive growth of data traffic in mobile communication system. Wireless network needs to provide effective support, and it has brought great challenges to the development of mobile communication system. Statistics show that about90%of data services occur indoors, and it is important for operators to provide good indoor coverage for these high speed data services. As an indoor solution, femtocells are used to provide high quality service for indoor users and improve network capacity.
Femtocells are introduced in the next generation wireless communication system, which changes the traditional network structure, called hierarchical macrocell and femtocell networks. Overlapping macrocells and femtocells are different in terms of application scenarios, coverage, network capacity, services support ability and transmission power. The macrocells and femtocells complement each other and jointly provide high quality services for wireless users. Therefore, the traditional radio resource management technologies cannot be directly applied in hierarchical networks. Radio resource management is the key to implement performance optimization of hierarchical networks. On the one hand, the overlapping coverage makes handover scenarios more complex, especially in the presence of a large number of femtocells. How to improve the user experience and reduce the frequent and unnecessary handovers is the focus of the researches of the handover algorithm in hierarchical networks. On the other hand, there is a contradiction between a variety of service requirements and the limited wireless bandwidth resources. Admission control for each service needs to be performed according to the technical characteristics of macrocells and femtocells to improve the utilization of the wireless resources, as well as guaranteeing the quality of service.
In this paper, the research focuses on handover and admission control technology of the radio resource management in hierarchical networks. The following aspects have been studied:
Users moving in hierarchical networks deploying multiple femtocells may experience frequent handovers in order to obtain higher transmission rate, which seriously increases the network load. Therefore, handover decision seeks to achieve a balance between user satisfaction and the network performance. Several factors influencing the decision making in the scene are analyzed, considering the bursty non real-time data service. The markov decision process model is used to formulate the handover decision problem. The data reward function denotes the amount of data transmitted via candidate networks, and the signaling cost function denotes the handover overhead. Users choose to handover the network with maximum reward. The simulation results show that the proposed handover scheme is effective and outperforms traditional polices.
The network connection time is related to user's mobility, the amount of data traffic, service arrival and available bandwidth. As a result, the network cannot obtain accurate network connection time when making admission decisions. The user motion model takes into consideration both the velocity uncertainty and the path uncertainty. User mobility prediction is based on the historical observation of the user location information. The service arriving to the femtocell is classified into four types which differ in signaling overhead on network. The partially observable markov decision process theory is utilized as the modeling tool, and the observation space and the observation function are given. Simulation results show the proposed admission control scheme effectively improves the resource utilization of the femtocell.
A variety of handover services and new services exist in hierarchical networks. The resource utilization of the femtocell in the existing admission control schemes is low, and an admission control and transfer scheme is proposed based on the traditional admission control schemes. When there are idle resources in a femtocell, the services connecting to a macrocell while users are located in the coverage of the femtocell could be chosen to handover to the femtocell. The problem is formulated as a semi markov decision process optimization problem. The system energy efficiency reward function is defined. Simulation results show that the proposed energy efficiency priority admission control and transfer strategy effectively improves the resource utilization of the femtocell with the maximum reward, and decreases blocking probability and dropping probability.
下一代的无线通信系统中引入家庭基站以后,改变了传统的网络结构,出现了宏基站/家庭基站分层网络。宏基站与家庭基站重叠覆盖,二者在应用场景、覆盖范围、网络容量、业务支持能力和发射功率等方面都存在较大差异,相互补充,共同为无线用户提供高质量服务。由于这种差异性,使得传统的无线资源管理技术不能直接应用于分层网络。无线资源管理是实现分层网络性能优化的关键。一方面,分层网络的重叠覆盖场景使得业务的切换更加复杂,尤其是在存在大量家庭基站的情况下,如何在提高用户体验的同时,减少频繁和不必要切换是分层网络切换算法研究的重点；另一方面,多样化的业务需求与有限的无线带宽资源之间存在矛盾,需要根据宏基站与家庭基站各自的技术特点,在保证一定服务质量的同时,针对不同业务进行接纳控制,提高无线资源的利用率。
本文研究内容集中在分层网络无线资源管理中的切换和接纳控制技术,进行如下几个方面的研究：
用户在部署有多个家庭基站的分层网络内运动,为了获得更高的传输速率,可能会在各小区之间进行频繁的切换,严重增加了网络的负载,切换决策需要在用户满意度与网络性能之间实现平衡。首先分析了场景中影响切换决策的几个因素,考虑了非实时性数据业务到达的突发性,然后将该场景的切换问题建模成马尔可夫决策过程模型,数据效用函数表示用户在候选网络中业务传输数据量,信令开销函数表示切换给网络带来的负载,选择切换到效用最大的目标网络。仿真结果表明了提出的切换方案与传方法相比有最大的效用。
用户的数据业务在家庭基站内的网络连接时间受到该用户的移动性、业务数据量、业务到达以及可用带宽的共同影响,网络在进行接纳决策时无法获得完整信息。针对该问题,首先给出了路径和速度的用户运动模型,根据对用户历史位置信息的观测对用户进行移动预测；然后分析了四类突发的数据业务到达事件,这四类事件将对网络产生不同的信令开销;最后利用部分可观测的马尔可夫决策过程理论,给出观测空间以及观测函数。仿真结果证明了提出的接纳控制方案有效提高了家庭基站的资源利用率。
分层网络中各小区存在各种切换业务以及新到达业务,针对现有的接纳控制方案中存在家庭基站资源利用率不高的问题,提出在传统接纳控制方案的基础上进行业务转移。当家庭基站中有空闲资源时,可以选择将连接到宏基站而处在家庭基站覆盖范围的业务切换到家庭基站。将上述问题用半马尔可夫决策过程理论建模,定义了网络的能量效用函数。仿真结果表明提出的能效优先的业务接纳和转移策略在获得最大效用的基础上,有效提高了家庭基站的资源利用率,降低了业务的阻塞率和掉话率。
With the rapid development of mobile Internet, the demand for accessing to the Internet via mobile communication network by users is increasing. Various types of wireless multimedia services requiring high quality service emerge, which promotes the explosive growth of data traffic in mobile communication system. Wireless network needs to provide effective support, and it has brought great challenges to the development of mobile communication system. Statistics show that about90%of data services occur indoors, and it is important for operators to provide good indoor coverage for these high speed data services. As an indoor solution, femtocells are used to provide high quality service for indoor users and improve network capacity.
Femtocells are introduced in the next generation wireless communication system, which changes the traditional network structure, called hierarchical macrocell and femtocell networks. Overlapping macrocells and femtocells are different in terms of application scenarios, coverage, network capacity, services support ability and transmission power. The macrocells and femtocells complement each other and jointly provide high quality services for wireless users. Therefore, the traditional radio resource management technologies cannot be directly applied in hierarchical networks. Radio resource management is the key to implement performance optimization of hierarchical networks. On the one hand, the overlapping coverage makes handover scenarios more complex, especially in the presence of a large number of femtocells. How to improve the user experience and reduce the frequent and unnecessary handovers is the focus of the researches of the handover algorithm in hierarchical networks. On the other hand, there is a contradiction between a variety of service requirements and the limited wireless bandwidth resources. Admission control for each service needs to be performed according to the technical characteristics of macrocells and femtocells to improve the utilization of the wireless resources, as well as guaranteeing the quality of service.
In this paper, the research focuses on handover and admission control technology of the radio resource management in hierarchical networks. The following aspects have been studied:
Users moving in hierarchical networks deploying multiple femtocells may experience frequent handovers in order to obtain higher transmission rate, which seriously increases the network load. Therefore, handover decision seeks to achieve a balance between user satisfaction and the network performance. Several factors influencing the decision making in the scene are analyzed, considering the bursty non real-time data service. The markov decision process model is used to formulate the handover decision problem. The data reward function denotes the amount of data transmitted via candidate networks, and the signaling cost function denotes the handover overhead. Users choose to handover the network with maximum reward. The simulation results show that the proposed handover scheme is effective and outperforms traditional polices.
The network connection time is related to user's mobility, the amount of data traffic, service arrival and available bandwidth. As a result, the network cannot obtain accurate network connection time when making admission decisions. The user motion model takes into consideration both the velocity uncertainty and the path uncertainty. User mobility prediction is based on the historical observation of the user location information. The service arriving to the femtocell is classified into four types which differ in signaling overhead on network. The partially observable markov decision process theory is utilized as the modeling tool, and the observation space and the observation function are given. Simulation results show the proposed admission control scheme effectively improves the resource utilization of the femtocell.
A variety of handover services and new services exist in hierarchical networks. The resource utilization of the femtocell in the existing admission control schemes is low, and an admission control and transfer scheme is proposed based on the traditional admission control schemes. When there are idle resources in a femtocell, the services connecting to a macrocell while users are located in the coverage of the femtocell could be chosen to handover to the femtocell. The problem is formulated as a semi markov decision process optimization problem. The system energy efficiency reward function is defined. Simulation results show that the proposed energy efficiency priority admission control and transfer strategy effectively improves the resource utilization of the femtocell with the maximum reward, and decreases blocking probability and dropping probability.
引文
[1]Cisco. Cisco Visual Networking Index:Global Mobile Data Traffic Forecast Update, 2012-2017[J].2013.
[2]Cullen J. Radioframe presentation[J]. Femtocell Europe,2008.
[3]Korinthios G, Theodoropoulou E, Marouda N, Mesogiti I, Nikolitsa E, Lyberopoulos G. Early experiences and lessons learned from femtocells[J]. Communications Magazine, IEEE,2009,47(9): 124-130.
[4]Humblet P, Raghothaman B, Srinivas A, Balasubramanian S, Patel C, Yavuz M. System design of cdma2000 femtocells[J]. Communications Magazine, IEEE,2009,47(9):92-100.
[5]Knisely D, Yoshizawa T, Favichia F. Standardization of femtocells in 3GPP[J]. Communications Magazine, IEEE,2009,47(9):68-75.
[6]Chiussi FM, Logothetis D, Widjaja I, Kataria D. Femtocells [Guest Editorial][J]. Communications Magazine, IEEE,2010,48(1):24-25.
[7]Claussen H, Ho LT, Samuel LG. An overview of the femtocell concept[J]. Bell Labs Technical Journal,2008,13(1):221-245.
[8]Zhang J, De la Roche G. Femtocells:technologies and deployment[M]. Wiley Online Library, 2010.
[9]Hasan SF, Siddique NH, Chakraborty S. Femtocell versus WiFi-A survey and comparison of architecture and performance:proceedings of the Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology,2009 Wireless VITAE 2009 1st International Conference on,2009[C]. IEEE.
[10]Chandrasekhar V, Andrews J, Gatherer A. Femtocell networks:a survey[J]. Communications Magazine, IEEE,2008,46(9):59-67.
[11]De La Roche G, Valcarce A, Lopez-Perez D, Zhang J. Access control mechanisms for femtocells[J]. Communications Magazine, IEEE,2010,48(1):33-39.
[12]Saunders S, Carlaw S, Giustina A, Bhat RR, Rao VS, Siegberg R. Femtocells:opportunities and challenges for business and technology[M]. Wiley,2009.
[13]Smallcellforum. http://www.smallcellforum.org/.
[14]Telecoms I. Media. Femtocell market status [M].2011.
[15]Xiao Z, Tan G-h, Li R-f, Yi K-c. Study on Current Research and Future Trends of Two-Tier Femto-Macro Networks:proceedings of the Wireless Communications, Networking and Mobile Computing (WiCOM),2012 8th International Conference on,2012[C]. IEEE.
[16]Project rGP. Evolved Universal Terrestrial Radio Access(E-UTRA) and Evolved Universal Radio Access Network(E-UTRAN) Overall description; Stage 2[J].3GPP TS36 300 version 1150 Release 11,2013.
[17]Claussen H. Performance of macro-and co-channel femtocells in a hierarchical cell structure: proceedings of the Personal, Indoor and Mobile Radio Communications,2007 IEEE 18th International Symposium on,2007[C]. IEEE.
[18]Damnjanovic A, Montojo J, Wei Y, Ji T, Luo T, Vajapeyam M, Yoo T, Song O, Malladi D. A survey on 3GPP heterogeneous networks[J]. Wireless Communications, IEEE,2011,18(3):10-21.
[19]Barbieri A, Damnjanovic A, Ji T, Montojo J, Wei Y, Malladi D, Song O, Horn G. LTE femtocells:system design and performance analysis[J]. Selected Areas in Communications, IEEE Journal on,2012,30(3):586-594.
[20]王映民,孙韶辉.TD-LTE技术原理与系统设计[M].人民邮电出版社,2010.
[21]L6pez-Perez D, Valcarce A, De La Roche G, Zhang J. OFDMA femtocells:A roadmap on interference avoidance[J]. Communications Magazine, IEEE,2009,47(9):41-48.
[22]Hamalainen S, Sanneck H, Sartori C. LTE Self-Organising Networks (SON):Network Management Automation for Operational Efficiency[M]. Wiley,2012.
[23]Aliu O, Imran A, Imran M, Evans B. A survey of self organisation in future cellular networks[J].2012.
[24]Andrews JG, Claussen H, Dohler M, Rangan S, Reed MC. Femtocells:Past, present, and future[J]. Selected Areas in Communications, IEEE Journal on,2012,30(3):497-508.
[25]张传福.第三代移动通信资源管理与新业务[M].人民邮电出版社,2008.
[26]Cardei M, Cardei I, Du D-Z. Resource management in wireless networking[M]. Springer Science+Business Media,2005.
[27]Magnusson P, Lundsjo J, Sachs J, Wallentin P. Radio resource management distribution in a beyond 3G multi-radio access architecture:proceedings of the Global Telecommunications Conference,2004 GLOBECOM'04 IEEE,2004[C]. IEEE.
[28]Jorguseski L, Prasad R. Overview of radio resource management (RRM) issues in multi-radio access systems:proceedings of the Wireless Technology,2004 7th European Conference on, 2004[C]. IEEE.
[29]Goldsmith A. Wireless communications[M]. Cambridge university press,2005.
[30]Juang R-T, Ting P, Lin H-P, Lin D-B. Interference management of femtocell in macro-cellular networks:proceedings of the Wireless Telecommunications Symposium (WTS), 2010,2010[C]. IEEE.
[31]Saquib N, Hossain E, Le LB, Kim DI. Interference management in OFDMA femtocell networks:Issues and approaches[J]. Wireless Communications, IEEE,2012,19(3):86-95.
[32]Yavuz M, Meshkati F, Nanda S, Pokhariyal A, Johnson N, Raghothaman B, Richardson A. Interference management and performance analysis of UMTS/HSPA+femtocells[J]. Communications Magazine, IEEE,2009,47(9):102-109.
[33]Elsherif AR, Ahmedin A, Ding Z, Liu X. Adaptive precoding for femtocell interference mitigation:proceedings of the Communications (ICC),2012 IEEE International Conference on, 2012[C]. IEEE.
[34]Jo H-S, Yook J-G, Mun C, Moon J. A self-organized uplink power control for cross-tier interference management in femtocell networks:proceedings of the Military Communications Conference,2008 MILCOM 2008 IEEE,2008[C]. IEEE.
[35]Lee H-C, Oh D-C, Lee Y-H. Mitigation of inter-femtocell interference with adaptive fractional frequency reuse:proceedings of the Communications (ICC),2010 IEEE International Conference on,2010[C]. IEEE.
[36]Sun Y, Jover RP, Wang X. Uplink interference mitigation for OFDMA femtocell networks[J]. Wireless Communications, IEEE Transactions on,2012,11(2):614-625.
[37]Jo H-S, Xia P, Andrews JG. Downlink femtocell networks:Open or closed?:proceedings of the Communications (ICC),2011 IEEE International Conference on,2011[C]. IEEE.
[38]Proposal NWI. Enhanced ICIC for non-CA based deployments of heterogeneous networks for LTE,"[J]. RP-100372,2010.
[39]Chandrasekhar V, Andrews JG, Muharemovic T, Shen Z, Gatherer A. Power control in two-tier femtocell networks[J]. Wireless Communications, IEEE Transactions on,2009,8(8): 4316-4328.
[40]Fodor G, Koutsimanis C, Racz A, Reider N, Simonsson A, Muller W. Intercell interference coordination in OFDMA networks and in the 3GPP long term evolution system[J]. Journal of Communications,2009,4(7):445-453.
[41]Rangan S, Madan R. Belief propagation methods for intercell interference coordination in femtocell networks[J]. Selected Areas in Communications, IEEE Journal on,2012,30(3):631-640.
[42]Rangan S. Femto-macro cellular interference control with subband scheduling and interference cancelation:proceedings of the GLOBECOM Workshops (GC Wkshps),2010 IEEE, 2010[C]. IEEE.
[43]Amirijoo M, Frenger P, Gunnarsson F, Kallin H, Moe J, Zetterberg K. Neighbor cell relation list and physical cell identity self-organization in LTE:proceedings of the Communications Workshops,2008 ICC Workshops'08 IEEE International Conference on,2008[C]. IEEE.
[44]Amirijoo M, Frenger P, Gunnarsson F, Kallin H, Moe J, Zetterberg K. Neighbor cell relation list and measured cell identity management in LTE:proceedings of the Network Operations and Management Symposium,2008 NOMS 2008 IEEE,2008[C]. IEEE.
[45]Oppolzer J, Bestak R. Physical Cell Identifier assignment in LTE-advanced networks: proceedings of the Wireless and Mobile Networking Conference (WMNC),2012 5th Joint IFIP, 2012[C]. IEEE.
[46]Han K, Woo S, Kang D, Choi S. Automatic neighboring BS list generation scheme for femtocell network:proceedings of the Ubiquitous and Future Networks (ICUFN),2010 Second International Conference on,2010[C]. IEEE.
[47]Golaup A, Mustapha M, Patanapongpibul LB. Femtocell access control strategy in UMTS and LTE[J]. Communications Magazine, IEEE,2009,47(9):117-123.
[48]Cheung WC, Quek TQ, Kountouris M. Spectrum allocation and optimization in femtocell networks:proceedings of the Communications (ICC),2012 IEEE International Conference on, 2012[C]. IEEE.
[49]Chen Y, Zhang J, Lin P, Zhang Q. Optimal pricing and spectrum allocation for wireless service provider on femtocell deployment:proceedings of the Communications (ICC),2011 IEEE International Conference on,2011[C]. IEEE.
[50]Li S, Xia H, Zeng Z, Huang Z, Wu H. User Classifying-based Hybrid Spectrum Allocation in Two-tier OFDMA Femtocell Networks:proceedings of the Vehicular Technology Conference (VTC Fall),2012 IEEE,2012[C]. IEEE.
[51]Haddad Y, Sagy E, Tashnady P. Analysis of an efficient channel assignment scheme for femtocell:proceedings of the Microwaves, Communications, Antennas and Electronics Systems (COMCAS),2011 IEEE International Conference on,2011[C]. IEEE.
[52]L6pez-Perez D, Ladanyi A, Juttner A, Zhang J. OFDMA femtocells:A self-organizing approach for frequency assignment:proceedings of the Personal, Indoor and Mobile Radio Communications,2009 IEEE 20th International Symposium on,2009[C]. IEEE.
[53]Bai Y, Zhou J, Liu L, Chen L, Otsuka H. Resource coordination and interference mitigation between macrocell and femtocell:proceedings of the Personal, Indoor and Mobile Radio Communications,2009 IEEE 20th International Symposium on,2009[C]. IEEE.
[54]Kim J, Cho D-H. A joint power and subchannel allocation scheme maximizing system capacity in dense femtocell downlink systems:proceedings of the Personal, Indoor and Mobile Radio Communications,2009 IEEE 20th International Symposium on,2009[C]. IEEE.
[55]周建明.无线异构网络的垂直切换[J].通信技术,2011,44(05)：97-99.
[56]林,克拉姆太克,方旭明,林楷,电子,张雪竹.无线与移动网络结构[M].人民邮电出版社,2002.
[57]Rappaport TS. Wireless communications:principles and practice[M]. Prentice Hall PTR New Jersey,1996.
[58]Nasser N, Hasswa A, Hassanein H. Handoffs in fourth generation heterogeneous networks[J]. Communications Magazine, IEEE,2006,44(10):96-103.
[59]Wang Y, Li W, Yu P, Qiu X. Automated handover optimization mechanism for LTE femtocells:proceedings of the Communications and Networking in China (CHINACOM),2012 7th International ICST Conference on,2012[C]. IEEE.
[60]Liu C, Wei J, Huang S, Cao Y. A Distance-Based Handover Scheme for Femtocell and Macrocell Overlaid Networks:proceedings of the Wireless Communications, Networking and Mobile Computing (WiCOM),2012 8th International Conference on,2012[C]. IEEE.
[61]Das K, Behera P. Spectrum access and handover strategy in femtocell network[D],2012.
[62]Rath A, Panwar S. Fast handover in cellular networks with femtocells:proceedings of the Communications (ICC),2012 IEEE International Conference on,2012[C]. IEEE.
[63]Chowdhury MZ, Jang YM. Handover management in high-dense femtocellular networks[J]. EURASIP Journal on Wireless Communications and Networking,2013,2013(1):1-21.
[64]Huang M. A Handover Scheme for TD-SCDMA Femtocell Networks:proceedings of the Computer and Information Technology (CIT),2012 IEEE 12th International Conference on, 2012[C].IEEE.
[65]Zheng W, Zhang H, Chu X, Wen X. Mobility robustness optimization in self-organizing LTE femtocell networks[J]. EURASIP Journal on Wireless Communications and Networking, 2013,2013(1):27.
[66]Guo T, Quddus Au, Tafazolli R. Seamless Handover for LTE Macro-Femto Networks Based on Reactive Data Bicasting[J].2012.
[67]Irvine J, Atkinson RC. An Advanced SOM Algorithm Applied to Handover Management within LTE[J].2013.
[68]Chen Y-S, Wu C-Y. A green handover protocol in two-tier OFDMA macrocell-femtocell networks[J]. Mathematical and Computer Modelling,2012.
[69]Ulvan A, Bestak R, Ulvan M. The study of handover procedure in LTE-based femtocell network:proceedings of the Wireless and Mobile Networking Conference (WMNC),2010 Third Joint IFIP,2010[C]. IEEE.
[70]Choi J-I, Seo W-K, Nam J-C, Park I-S, Cho Y-Z. Handover decision algorithm based on available data volume in hierarchical macro/femto-cell networks:proceedings of the Communications and Electronics (ICCE),2012 Fourth International Conference on,2012[C]. IEEE.
[71]柴蓉,肖敏,唐伦,陈前斌.异构网络垂直切换性能参数分析及算法研究[J].重庆邮电大学学报：自然科学版,2010,(001)：63-70.
[72]Pollini GP. Trends in handover design[J]. Communications Magazine, IEEE,1996,34(3): 82-90.
[73]Zahran AH, Liang B, Saleh A. Signal threshold adaptation for vertical handoff in heterogeneous wireless networks[J]. Mobile Networks and Applications,2006,11(4):625-640.
[74]Yang K, Gondal I, Qiu B, Dooley LS. Combined SINR based vertical handoff algorithm for next generation heterogeneous wireless networks:proceedings of the Global Telecommunications Conference,2007 GLOBECOM"07 IEEE,2007[C]. IEEE.
[75]Yang K, Gondal I, Qiu B. Multi-dimensional adaptive SINR based vertical handoff for heterogeneous wireless networks[J]. Communications Letters, IEEE,2008 12(6):438-440.
[76]Liang B, Zahran AH, Saleh AO. Application signal threshold adaptation for vertical handoff in heterogeneous wireless networks[M]. NETWORKING 2005 Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communications Systems; Springer.2005:1193-1205.
[77]Mohanty S, Akyildiz IF. A cross-layer (layer 2+3) handoff management protocol for next-generation wireless systems[J]. Mobile Computing, IEEE Transactions on,2006,5(10): 1347-1360.
[78]Park HS, Yoon SH, Kim TH, Park JS, Do MS, Lee JY. Vertical Hando. Procedure and Algorithm between IEEE802.11 WLAN and CDMA Cellular Network[M]. Mobile Communications; Springer.2003:103-112.
[79]Chang B-J, Chen J-F. Cross-layer-based adaptive vertical handoff with predictive RSS in heterogeneous wireless networks[J]. Vehicular Technology, IEEE Transactions on,2008,57(6): 3679-3692.
[80]Xenakis D, Passas N, Verikoukis C. A novel handover decision policy for reducing power transmissions in the two-tier LTE network:proceedings of the Communications (ICC),2012 IEEE International Conference on,2012[C]. IEEE.
[81]Xenakis D, Passas N, Verikoukis C. An energy-centric handover decision algorithm for the integrated LTE macrocell-femtocell network[J]. Computer Communications,2012.
[82]Yan X, Mani N, Cekercioglu Y. A traveling distance prediction based method to minimize unnecessary handovers from cellular networks to WLANs[J]. Communications Letters, IEEE, 2008,12(1):14-16.
[83]Yan X, SBekercioglu YA, Narayanan S. A probability based triggering time estimation method for handover optimization [M]. preparation.
[84]Zhang W. Handover decision using fuzzy MADM in heterogeneous networks:proceedings of the Wireless Communications and Networking Conference,2004 WCNC 2004 IEEE,2004[C]. IEEE.
[85]Hou J, O'Brien DC. Vertical handover-decision-making algorithm using fuzzy logic for the integrated Radio-and-OW system[J]. Wireless Communications, IEEE Transactions on,2006,5(1): 176-185.
[86]Xia L, Jiang L-g, He C. A novel fuzzy logic vertical handoff algorithm with aid of differential prediction and pre-decision method:proceedings of the Communications,2007 ICC07 IEEE International Conference on,2007[C]. IEEE.
[87]Calhan A, Ceken C. Speed sensitive-energy aware adaptive fuzzy logic based vertical handoff decision algorithm:proceedings of the Systems, Signals and Image Processing (IWSSIP), 201118th International Conference on,2011 [C]. IEEE.
[88]Majlesi A, Khalaj BH. An adaptive fuzzy logic based handoff algorithm for interworking between WLANs and mobile networks:proceedings of the Personal, Indoor and Mobile Radio Communications,2002 The 13th IEEE International Symposium on,2002[C]. IEEE.
[89]Tripathi ND, Reed JH, VanLandingham HF. Adaptive handoff algorithms for cellular overlay systems using fuzzy logic:proceedings of the Vehicular Technology Conference,1999 IEEE 49th, 1999[C]. IEEE.
[90]Nasser N, Guizani S, A1-Masri E. Middleware vertical handoff manager:A neural network-based solution:proceedings of the Communications,2007 ICC'07 IEEE International Conference on,2007[C]. IEEE.
[91]Stevens-Navarro E, Lin Y, Wong VW. An MDP-based vertical handoff decision algorithm for heterogeneous wireless networks[J]. Vehicular Technology, IEEE Transactions on,2008,57(2): 1243-1254.
[92]Abhishek R, Jitae S, Navrati S. Multi-Objective Handover in LTE Macro/Femto-Cell Networks[J]. Journal of Communications and Networks, IEEE,2012,14(5):578-587.
[93]Shen W, Zeng Q-A. Cost-function-based network selection strategy in integrated wireless and mobile nerworks[J]. Vehicular Technology, IEEE Transactions on,2008,57(6):3778-3788.
[94]Lee S, Sriram K, Kim K, Kim YH, Golmie N. Vertical handoff decision algorithms for providing optimized performance in heterogeneous wireless networks[J]. Vehicular Technology, IEEE Transactions on,2009,58(2):865-881.
[95]Tabrizi H, Farhadi G, Cioffi J. A Learning-Based Network Selection Method in Heterogeneous Wireless Systems:proceedings of the Global Telecommunications Conference (GLOBECOM 2011),2011 IEEE,2011 [C]. IEEE.
[96]Niyato D, Hossain E. Dynamics of network selection in heterogeneous wireless networks:an evolutionary game approach[J]. Vehicular Technology, IEEE Transactions on,2009,58(4): 2008-2017.
[97]Niyato D, Hossain E. A cooperative game framework for bandwidth allocation in 4G heterogeneous wireless networks:proceedings of the Communications,2006 ICC'06 IEEE International Conference on,2006[C]. IEEE.
[98]Kim YC, Lee DE, Lee BJ, Kim YS, Mukherjee B. Dynamic channel reservation based on mobility in wireless ATM networks[J]. Communications Magazine, IEEE,1999,37(11):47-51.
[99]Yao J, Mark JW, Wong TC, Chew YH, Lye KM, Chua K-C. Virtual partitioning resource allocation for multiclass traffic in cellular systems with QoS constraints[J]. Vehicular Technology, IEEE Transactions on,2004,53(3):847-864.
[100]Epstein B, Schwartz M. Reservation strategies for multi-media traffic in a wireless environment:proceedings of the Vehicular Technology Conference,1995 IEEE 45th,1995[C]. IEEE.
[101]Singh S, Krishnamurthy V, Poor HV. Integrated voice/data call admission control for wireless DS-CDMA systems[J]. Signal Processing, IEEE Transactions on,2002,50(6):1483-1495.
[102]Chou C-T, Shin KG Analysis of adaptive bandwidth allocation in wireless networks with multilevel degradable quality of service[J]. Mobile Computing, IEEE Transactions on,2004,3(1): 5-17.
[103]Holliday T, Goldsmith A, Bambos N, Glynn P. Distributed power and admission control for time-varying wireless networks:proceedings of the Information Theory,2004 ISIT 2004 Proceedings International Symposium on,2004[C]. IEEE.
[104]Hou J, Yang J, Papavassiliou S. Integration of pricing with call admission control to meet QoS requirements in cellular networks[J]. Parallel and Distributed Systems, IEEE Transactions on, 2002,13(9):898-910.
[105]Ormond O, Murphy J, Muntean G-M. Utility-based intelligent network selection in beyond 3G systems:proceedings of the Communications,2006 ICC'06 IEEE International Conference on, 2006[C]. IEEE.
[106]王莹,张平.无线资源管理[M].北京邮电大学出版社,2005.
[107]Yu F, Krishnamurthy V. Optimal joint session admission control in integrated WLAN and CDMA cellular networks with vertical handoff[J]. Mobile Computing, IEEE Transactions on, 2007,6(1):126-139.
[108]Haung Y-R, Ho J-M. Distributed call admission control for a heterogeneous PCS network[J]. Computers, IEEE Transactions on,2002,51(12):1400-1409.
[109]Namal S, Ghaboosi K, Bennis M, MacKenzie AB, Latva-aho M. Joint admission control& interference avoidance in self-organized femtocells:proceedings of the Signals, Systems and Computers (ASILOMAR),2010 Conference Record of the Forty Fourth Asilomar Conference on, 2010[C]. IEEE.
[110]Ngo DT, Le LB, Le-Ngoc T, Hossain E, Kim DI. Distributed interference management in femtocell networks:proceedings of the Vehicular Technology Conference (VTC Fall),2011 IEEE, 2011[C]. IEEE.
[111]Li X, Qian L, Kataria D. Downlink power control in co-channel macrocell femtocell overlay: proceedings of the Information Sciences and Systems,2009 CISS 2009 43rd Annual Conference on,2009[C]. IEEE.
[112]Moon J-M, Cho D-H. Novel handoff decision algorithm in hierarchical macro/femto-cell networks:proceedings of the Wireless Communications and Networking Conference (WCNC), 2010 IEEE,2010[C]. IEEE.
[113]Shaohong W, Xin Z, Ruiming Z, Zhiwei Y, Yinglong F, Dacheng Y. Handover study concerning mobility in the two-hierarchy network:proceedings of the Vehicular Technology Conference,2009 VTC Spring 2009 IEEE 69th,2009[C]. IEEE.
[114]Zhang J, Chan HC, Leung VC. WLC14-6:A Location-Based Vertical Handoff Decision Algorithm for Heterogeneous Mobile Networks:proceedings of the Global Telecommunications Conference,2006 GLOBECOM'06 IEEE,2006[C]. IEEE.
[115]Sun C, Stevens-Navarro E, Wong VW. A constrained MDP-based vertical handoff decision algorithm for 4G wireless networks:proceedings of the Communications,2008 ICC'08 IEEE International Conference on,2008 [C]. IEEE.
[116]Puterman ML. Markov decision processes:discrete stochastic dynamic programming[M], Wiley-Interscience,2009.
[117]White D. Markov decision processes[M]. IMA,1993.
[118]Song W, Zhuang W. QoS provisioning via admission control in cellular/wireless LAN interworking:proceedings of the Broadband Networks,2005 BroadNets 2005 2nd International Conference on,2005[C]. IEEE.
[119]Song W, Jiang H, Zhuang W, Saleh A. Call admission control for integrated voice/data services in cellular/WLAN interworking:proceedings of the Communications,2006 ICC'06 IEEE International Conference on,2006[C]. IEEE.
[120]Chan H, Fan P, Cao Z. A utility-based network selection scheme for multiple services in heterogeneous networks:proceedings of the Wireless Networks, Communications and Mobile Computing,2005 International Conference on,2005[C]. IEEE.
[121]Chen Y-H, Chang C-J, Huang CY. Fuzzy Q-learaing admission control for WCDMA/WLAN heterogeneous networks with multimedia traffic[J]. Mobile Computing, IEEE Transactions on,2009,8(11):1469-1479.
[122]Zhang W. Algorithms for partially observable Markov decision processes[D]:Citeseer, 2001.
[123]White III CC. A survey of solution techniques for the partially observed Markov decision process[J]. Annals of Operations Research,1991,32(1):215-230.
[124]Smallwood RD, Sondik EJ. The optimal control of partially observable Markov processes over a finite horizon[J]. Operations Research,1973,21(5):1071-1088.
[125]Liang B, Haas ZJ. Predictive distance-based mobility management for multidimensional PCS networks[J]. Networking, IEEE/ACM Transactions on,2003,11(5):718-732.
[126]奚宏生.随机过程[M].中国科学技术大学出版社,2009.
[127]Chen Y, Zhang S, Xu S, Li GY. Fundamental trade-offs on green wireless networks[J]. Communications Magazine, IEEE,2011,49(6):30-37.
[128]Fehske A, Fettweis G, Malmodin J, Biczok G. The Global Carbon Footprint of Mobile Communications-The Ecological and Economic Perspective[J]. Communications Magazine, IEEE, 2011,49(8):55-62.
[129]Nasser N, Hassanein H. An optimal and fair call admission control policy for seamless handoff in multimedia wireless networks with QoS guarantees:proceedings of the Global Telecommunications Conference,2004 GLOBECOM'04 IEEE,2004[C]. IEEE.
[130]Le LB, Hoang DT, Niyato D, Hossain E, Kim DI. Joint load balancing and admission control in OFDMA-based femtocell networks:proceedings of the Communications (ICC),2012 IEEE International Conference on,2012[C]. IEEE.
[131]Chen H, Cheng C-C, Yeh H-H. Guard-channel-based incremental and dynamic optimization on call admission control for next-generation qos-aware heterogeneous systems[J]. Vehicular Technology, IEEE Transactions on,2008,57(5):3064-3082.
[132]Bertsekas DP. Dynamic programming and optimal control[M]. Athena Scientific Belmont, 1995.
[133]Tijms HC. Stochastic Modeling and Analysis:A Computational Approach[M]. John Wiley and Sons,1986.
[134]Auer G, Blume O, Giannini V. D2.3:Energy Efficiency Analysis of the Reference Systems, Areas of Improvements and Target Breakdown:proceedings of the INFSO-ICT-247733 EARTH (Energy Aware Radio and NeTwork TecHnologies),2010[C].
[135]Niu Z. TANGO:traffic-aware network planning and green operation[J]. Wireless Communications, IEEE,2011,18(5):25-29.
[136]Auer G, Giannini V, Desset C, Godor I, Skillermark P, Olsson M, Imran MA, Sabella D, Gonzalez MJ, Blume O. How much energy is needed to run a wireless network?[J]. Wireless Communications, IEEE,2011,18(5):40-49.
[2]Cullen J. Radioframe presentation[J]. Femtocell Europe,2008.
[3]Korinthios G, Theodoropoulou E, Marouda N, Mesogiti I, Nikolitsa E, Lyberopoulos G. Early experiences and lessons learned from femtocells[J]. Communications Magazine, IEEE,2009,47(9): 124-130.
[4]Humblet P, Raghothaman B, Srinivas A, Balasubramanian S, Patel C, Yavuz M. System design of cdma2000 femtocells[J]. Communications Magazine, IEEE,2009,47(9):92-100.
[5]Knisely D, Yoshizawa T, Favichia F. Standardization of femtocells in 3GPP[J]. Communications Magazine, IEEE,2009,47(9):68-75.
[6]Chiussi FM, Logothetis D, Widjaja I, Kataria D. Femtocells [Guest Editorial][J]. Communications Magazine, IEEE,2010,48(1):24-25.
[7]Claussen H, Ho LT, Samuel LG. An overview of the femtocell concept[J]. Bell Labs Technical Journal,2008,13(1):221-245.
[8]Zhang J, De la Roche G. Femtocells:technologies and deployment[M]. Wiley Online Library, 2010.
[9]Hasan SF, Siddique NH, Chakraborty S. Femtocell versus WiFi-A survey and comparison of architecture and performance:proceedings of the Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology,2009 Wireless VITAE 2009 1st International Conference on,2009[C]. IEEE.
[10]Chandrasekhar V, Andrews J, Gatherer A. Femtocell networks:a survey[J]. Communications Magazine, IEEE,2008,46(9):59-67.
[11]De La Roche G, Valcarce A, Lopez-Perez D, Zhang J. Access control mechanisms for femtocells[J]. Communications Magazine, IEEE,2010,48(1):33-39.
[12]Saunders S, Carlaw S, Giustina A, Bhat RR, Rao VS, Siegberg R. Femtocells:opportunities and challenges for business and technology[M]. Wiley,2009.
[13]Smallcellforum. http://www.smallcellforum.org/.
[14]Telecoms I. Media. Femtocell market status [M].2011.
[15]Xiao Z, Tan G-h, Li R-f, Yi K-c. Study on Current Research and Future Trends of Two-Tier Femto-Macro Networks:proceedings of the Wireless Communications, Networking and Mobile Computing (WiCOM),2012 8th International Conference on,2012[C]. IEEE.
[16]Project rGP. Evolved Universal Terrestrial Radio Access(E-UTRA) and Evolved Universal Radio Access Network(E-UTRAN) Overall description; Stage 2[J].3GPP TS36 300 version 1150 Release 11,2013.
[17]Claussen H. Performance of macro-and co-channel femtocells in a hierarchical cell structure: proceedings of the Personal, Indoor and Mobile Radio Communications,2007 IEEE 18th International Symposium on,2007[C]. IEEE.
[18]Damnjanovic A, Montojo J, Wei Y, Ji T, Luo T, Vajapeyam M, Yoo T, Song O, Malladi D. A survey on 3GPP heterogeneous networks[J]. Wireless Communications, IEEE,2011,18(3):10-21.
[19]Barbieri A, Damnjanovic A, Ji T, Montojo J, Wei Y, Malladi D, Song O, Horn G. LTE femtocells:system design and performance analysis[J]. Selected Areas in Communications, IEEE Journal on,2012,30(3):586-594.
[20]王映民,孙韶辉.TD-LTE技术原理与系统设计[M].人民邮电出版社,2010.
[21]L6pez-Perez D, Valcarce A, De La Roche G, Zhang J. OFDMA femtocells:A roadmap on interference avoidance[J]. Communications Magazine, IEEE,2009,47(9):41-48.
[22]Hamalainen S, Sanneck H, Sartori C. LTE Self-Organising Networks (SON):Network Management Automation for Operational Efficiency[M]. Wiley,2012.
[23]Aliu O, Imran A, Imran M, Evans B. A survey of self organisation in future cellular networks[J].2012.
[24]Andrews JG, Claussen H, Dohler M, Rangan S, Reed MC. Femtocells:Past, present, and future[J]. Selected Areas in Communications, IEEE Journal on,2012,30(3):497-508.
[25]张传福.第三代移动通信资源管理与新业务[M].人民邮电出版社,2008.
[26]Cardei M, Cardei I, Du D-Z. Resource management in wireless networking[M]. Springer Science+Business Media,2005.
[27]Magnusson P, Lundsjo J, Sachs J, Wallentin P. Radio resource management distribution in a beyond 3G multi-radio access architecture:proceedings of the Global Telecommunications Conference,2004 GLOBECOM'04 IEEE,2004[C]. IEEE.
[28]Jorguseski L, Prasad R. Overview of radio resource management (RRM) issues in multi-radio access systems:proceedings of the Wireless Technology,2004 7th European Conference on, 2004[C]. IEEE.
[29]Goldsmith A. Wireless communications[M]. Cambridge university press,2005.
[30]Juang R-T, Ting P, Lin H-P, Lin D-B. Interference management of femtocell in macro-cellular networks:proceedings of the Wireless Telecommunications Symposium (WTS), 2010,2010[C]. IEEE.
[31]Saquib N, Hossain E, Le LB, Kim DI. Interference management in OFDMA femtocell networks:Issues and approaches[J]. Wireless Communications, IEEE,2012,19(3):86-95.
[32]Yavuz M, Meshkati F, Nanda S, Pokhariyal A, Johnson N, Raghothaman B, Richardson A. Interference management and performance analysis of UMTS/HSPA+femtocells[J]. Communications Magazine, IEEE,2009,47(9):102-109.
[33]Elsherif AR, Ahmedin A, Ding Z, Liu X. Adaptive precoding for femtocell interference mitigation:proceedings of the Communications (ICC),2012 IEEE International Conference on, 2012[C]. IEEE.
[34]Jo H-S, Yook J-G, Mun C, Moon J. A self-organized uplink power control for cross-tier interference management in femtocell networks:proceedings of the Military Communications Conference,2008 MILCOM 2008 IEEE,2008[C]. IEEE.
[35]Lee H-C, Oh D-C, Lee Y-H. Mitigation of inter-femtocell interference with adaptive fractional frequency reuse:proceedings of the Communications (ICC),2010 IEEE International Conference on,2010[C]. IEEE.
[36]Sun Y, Jover RP, Wang X. Uplink interference mitigation for OFDMA femtocell networks[J]. Wireless Communications, IEEE Transactions on,2012,11(2):614-625.
[37]Jo H-S, Xia P, Andrews JG. Downlink femtocell networks:Open or closed?:proceedings of the Communications (ICC),2011 IEEE International Conference on,2011[C]. IEEE.
[38]Proposal NWI. Enhanced ICIC for non-CA based deployments of heterogeneous networks for LTE,"[J]. RP-100372,2010.
[39]Chandrasekhar V, Andrews JG, Muharemovic T, Shen Z, Gatherer A. Power control in two-tier femtocell networks[J]. Wireless Communications, IEEE Transactions on,2009,8(8): 4316-4328.
[40]Fodor G, Koutsimanis C, Racz A, Reider N, Simonsson A, Muller W. Intercell interference coordination in OFDMA networks and in the 3GPP long term evolution system[J]. Journal of Communications,2009,4(7):445-453.
[41]Rangan S, Madan R. Belief propagation methods for intercell interference coordination in femtocell networks[J]. Selected Areas in Communications, IEEE Journal on,2012,30(3):631-640.
[42]Rangan S. Femto-macro cellular interference control with subband scheduling and interference cancelation:proceedings of the GLOBECOM Workshops (GC Wkshps),2010 IEEE, 2010[C]. IEEE.
[43]Amirijoo M, Frenger P, Gunnarsson F, Kallin H, Moe J, Zetterberg K. Neighbor cell relation list and physical cell identity self-organization in LTE:proceedings of the Communications Workshops,2008 ICC Workshops'08 IEEE International Conference on,2008[C]. IEEE.
[44]Amirijoo M, Frenger P, Gunnarsson F, Kallin H, Moe J, Zetterberg K. Neighbor cell relation list and measured cell identity management in LTE:proceedings of the Network Operations and Management Symposium,2008 NOMS 2008 IEEE,2008[C]. IEEE.
[45]Oppolzer J, Bestak R. Physical Cell Identifier assignment in LTE-advanced networks: proceedings of the Wireless and Mobile Networking Conference (WMNC),2012 5th Joint IFIP, 2012[C]. IEEE.
[46]Han K, Woo S, Kang D, Choi S. Automatic neighboring BS list generation scheme for femtocell network:proceedings of the Ubiquitous and Future Networks (ICUFN),2010 Second International Conference on,2010[C]. IEEE.
[47]Golaup A, Mustapha M, Patanapongpibul LB. Femtocell access control strategy in UMTS and LTE[J]. Communications Magazine, IEEE,2009,47(9):117-123.
[48]Cheung WC, Quek TQ, Kountouris M. Spectrum allocation and optimization in femtocell networks:proceedings of the Communications (ICC),2012 IEEE International Conference on, 2012[C]. IEEE.
[49]Chen Y, Zhang J, Lin P, Zhang Q. Optimal pricing and spectrum allocation for wireless service provider on femtocell deployment:proceedings of the Communications (ICC),2011 IEEE International Conference on,2011[C]. IEEE.
[50]Li S, Xia H, Zeng Z, Huang Z, Wu H. User Classifying-based Hybrid Spectrum Allocation in Two-tier OFDMA Femtocell Networks:proceedings of the Vehicular Technology Conference (VTC Fall),2012 IEEE,2012[C]. IEEE.
[51]Haddad Y, Sagy E, Tashnady P. Analysis of an efficient channel assignment scheme for femtocell:proceedings of the Microwaves, Communications, Antennas and Electronics Systems (COMCAS),2011 IEEE International Conference on,2011[C]. IEEE.
[52]L6pez-Perez D, Ladanyi A, Juttner A, Zhang J. OFDMA femtocells:A self-organizing approach for frequency assignment:proceedings of the Personal, Indoor and Mobile Radio Communications,2009 IEEE 20th International Symposium on,2009[C]. IEEE.
[53]Bai Y, Zhou J, Liu L, Chen L, Otsuka H. Resource coordination and interference mitigation between macrocell and femtocell:proceedings of the Personal, Indoor and Mobile Radio Communications,2009 IEEE 20th International Symposium on,2009[C]. IEEE.
[54]Kim J, Cho D-H. A joint power and subchannel allocation scheme maximizing system capacity in dense femtocell downlink systems:proceedings of the Personal, Indoor and Mobile Radio Communications,2009 IEEE 20th International Symposium on,2009[C]. IEEE.
[55]周建明.无线异构网络的垂直切换[J].通信技术,2011,44(05)：97-99.
[56]林,克拉姆太克,方旭明,林楷,电子,张雪竹.无线与移动网络结构[M].人民邮电出版社,2002.
[57]Rappaport TS. Wireless communications:principles and practice[M]. Prentice Hall PTR New Jersey,1996.
[58]Nasser N, Hasswa A, Hassanein H. Handoffs in fourth generation heterogeneous networks[J]. Communications Magazine, IEEE,2006,44(10):96-103.
[59]Wang Y, Li W, Yu P, Qiu X. Automated handover optimization mechanism for LTE femtocells:proceedings of the Communications and Networking in China (CHINACOM),2012 7th International ICST Conference on,2012[C]. IEEE.
[60]Liu C, Wei J, Huang S, Cao Y. A Distance-Based Handover Scheme for Femtocell and Macrocell Overlaid Networks:proceedings of the Wireless Communications, Networking and Mobile Computing (WiCOM),2012 8th International Conference on,2012[C]. IEEE.
[61]Das K, Behera P. Spectrum access and handover strategy in femtocell network[D],2012.
[62]Rath A, Panwar S. Fast handover in cellular networks with femtocells:proceedings of the Communications (ICC),2012 IEEE International Conference on,2012[C]. IEEE.
[63]Chowdhury MZ, Jang YM. Handover management in high-dense femtocellular networks[J]. EURASIP Journal on Wireless Communications and Networking,2013,2013(1):1-21.
[64]Huang M. A Handover Scheme for TD-SCDMA Femtocell Networks:proceedings of the Computer and Information Technology (CIT),2012 IEEE 12th International Conference on, 2012[C].IEEE.
[65]Zheng W, Zhang H, Chu X, Wen X. Mobility robustness optimization in self-organizing LTE femtocell networks[J]. EURASIP Journal on Wireless Communications and Networking, 2013,2013(1):27.
[66]Guo T, Quddus Au, Tafazolli R. Seamless Handover for LTE Macro-Femto Networks Based on Reactive Data Bicasting[J].2012.
[67]Irvine J, Atkinson RC. An Advanced SOM Algorithm Applied to Handover Management within LTE[J].2013.
[68]Chen Y-S, Wu C-Y. A green handover protocol in two-tier OFDMA macrocell-femtocell networks[J]. Mathematical and Computer Modelling,2012.
[69]Ulvan A, Bestak R, Ulvan M. The study of handover procedure in LTE-based femtocell network:proceedings of the Wireless and Mobile Networking Conference (WMNC),2010 Third Joint IFIP,2010[C]. IEEE.
[70]Choi J-I, Seo W-K, Nam J-C, Park I-S, Cho Y-Z. Handover decision algorithm based on available data volume in hierarchical macro/femto-cell networks:proceedings of the Communications and Electronics (ICCE),2012 Fourth International Conference on,2012[C]. IEEE.
[71]柴蓉,肖敏,唐伦,陈前斌.异构网络垂直切换性能参数分析及算法研究[J].重庆邮电大学学报：自然科学版,2010,(001)：63-70.
[72]Pollini GP. Trends in handover design[J]. Communications Magazine, IEEE,1996,34(3): 82-90.
[73]Zahran AH, Liang B, Saleh A. Signal threshold adaptation for vertical handoff in heterogeneous wireless networks[J]. Mobile Networks and Applications,2006,11(4):625-640.
[74]Yang K, Gondal I, Qiu B, Dooley LS. Combined SINR based vertical handoff algorithm for next generation heterogeneous wireless networks:proceedings of the Global Telecommunications Conference,2007 GLOBECOM"07 IEEE,2007[C]. IEEE.
[75]Yang K, Gondal I, Qiu B. Multi-dimensional adaptive SINR based vertical handoff for heterogeneous wireless networks[J]. Communications Letters, IEEE,2008 12(6):438-440.
[76]Liang B, Zahran AH, Saleh AO. Application signal threshold adaptation for vertical handoff in heterogeneous wireless networks[M]. NETWORKING 2005 Networking Technologies, Services, and Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communications Systems; Springer.2005:1193-1205.
[77]Mohanty S, Akyildiz IF. A cross-layer (layer 2+3) handoff management protocol for next-generation wireless systems[J]. Mobile Computing, IEEE Transactions on,2006,5(10): 1347-1360.
[78]Park HS, Yoon SH, Kim TH, Park JS, Do MS, Lee JY. Vertical Hando. Procedure and Algorithm between IEEE802.11 WLAN and CDMA Cellular Network[M]. Mobile Communications; Springer.2003:103-112.
[79]Chang B-J, Chen J-F. Cross-layer-based adaptive vertical handoff with predictive RSS in heterogeneous wireless networks[J]. Vehicular Technology, IEEE Transactions on,2008,57(6): 3679-3692.
[80]Xenakis D, Passas N, Verikoukis C. A novel handover decision policy for reducing power transmissions in the two-tier LTE network:proceedings of the Communications (ICC),2012 IEEE International Conference on,2012[C]. IEEE.
[81]Xenakis D, Passas N, Verikoukis C. An energy-centric handover decision algorithm for the integrated LTE macrocell-femtocell network[J]. Computer Communications,2012.
[82]Yan X, Mani N, Cekercioglu Y. A traveling distance prediction based method to minimize unnecessary handovers from cellular networks to WLANs[J]. Communications Letters, IEEE, 2008,12(1):14-16.
[83]Yan X, SBekercioglu YA, Narayanan S. A probability based triggering time estimation method for handover optimization [M]. preparation.
[84]Zhang W. Handover decision using fuzzy MADM in heterogeneous networks:proceedings of the Wireless Communications and Networking Conference,2004 WCNC 2004 IEEE,2004[C]. IEEE.
[85]Hou J, O'Brien DC. Vertical handover-decision-making algorithm using fuzzy logic for the integrated Radio-and-OW system[J]. Wireless Communications, IEEE Transactions on,2006,5(1): 176-185.
[86]Xia L, Jiang L-g, He C. A novel fuzzy logic vertical handoff algorithm with aid of differential prediction and pre-decision method:proceedings of the Communications,2007 ICC07 IEEE International Conference on,2007[C]. IEEE.
[87]Calhan A, Ceken C. Speed sensitive-energy aware adaptive fuzzy logic based vertical handoff decision algorithm:proceedings of the Systems, Signals and Image Processing (IWSSIP), 201118th International Conference on,2011 [C]. IEEE.
[88]Majlesi A, Khalaj BH. An adaptive fuzzy logic based handoff algorithm for interworking between WLANs and mobile networks:proceedings of the Personal, Indoor and Mobile Radio Communications,2002 The 13th IEEE International Symposium on,2002[C]. IEEE.
[89]Tripathi ND, Reed JH, VanLandingham HF. Adaptive handoff algorithms for cellular overlay systems using fuzzy logic:proceedings of the Vehicular Technology Conference,1999 IEEE 49th, 1999[C]. IEEE.
[90]Nasser N, Guizani S, A1-Masri E. Middleware vertical handoff manager:A neural network-based solution:proceedings of the Communications,2007 ICC'07 IEEE International Conference on,2007[C]. IEEE.
[91]Stevens-Navarro E, Lin Y, Wong VW. An MDP-based vertical handoff decision algorithm for heterogeneous wireless networks[J]. Vehicular Technology, IEEE Transactions on,2008,57(2): 1243-1254.
[92]Abhishek R, Jitae S, Navrati S. Multi-Objective Handover in LTE Macro/Femto-Cell Networks[J]. Journal of Communications and Networks, IEEE,2012,14(5):578-587.
[93]Shen W, Zeng Q-A. Cost-function-based network selection strategy in integrated wireless and mobile nerworks[J]. Vehicular Technology, IEEE Transactions on,2008,57(6):3778-3788.
[94]Lee S, Sriram K, Kim K, Kim YH, Golmie N. Vertical handoff decision algorithms for providing optimized performance in heterogeneous wireless networks[J]. Vehicular Technology, IEEE Transactions on,2009,58(2):865-881.
[95]Tabrizi H, Farhadi G, Cioffi J. A Learning-Based Network Selection Method in Heterogeneous Wireless Systems:proceedings of the Global Telecommunications Conference (GLOBECOM 2011),2011 IEEE,2011 [C]. IEEE.
[96]Niyato D, Hossain E. Dynamics of network selection in heterogeneous wireless networks:an evolutionary game approach[J]. Vehicular Technology, IEEE Transactions on,2009,58(4): 2008-2017.
[97]Niyato D, Hossain E. A cooperative game framework for bandwidth allocation in 4G heterogeneous wireless networks:proceedings of the Communications,2006 ICC'06 IEEE International Conference on,2006[C]. IEEE.
[98]Kim YC, Lee DE, Lee BJ, Kim YS, Mukherjee B. Dynamic channel reservation based on mobility in wireless ATM networks[J]. Communications Magazine, IEEE,1999,37(11):47-51.
[99]Yao J, Mark JW, Wong TC, Chew YH, Lye KM, Chua K-C. Virtual partitioning resource allocation for multiclass traffic in cellular systems with QoS constraints[J]. Vehicular Technology, IEEE Transactions on,2004,53(3):847-864.
[100]Epstein B, Schwartz M. Reservation strategies for multi-media traffic in a wireless environment:proceedings of the Vehicular Technology Conference,1995 IEEE 45th,1995[C]. IEEE.
[101]Singh S, Krishnamurthy V, Poor HV. Integrated voice/data call admission control for wireless DS-CDMA systems[J]. Signal Processing, IEEE Transactions on,2002,50(6):1483-1495.
[102]Chou C-T, Shin KG Analysis of adaptive bandwidth allocation in wireless networks with multilevel degradable quality of service[J]. Mobile Computing, IEEE Transactions on,2004,3(1): 5-17.
[103]Holliday T, Goldsmith A, Bambos N, Glynn P. Distributed power and admission control for time-varying wireless networks:proceedings of the Information Theory,2004 ISIT 2004 Proceedings International Symposium on,2004[C]. IEEE.
[104]Hou J, Yang J, Papavassiliou S. Integration of pricing with call admission control to meet QoS requirements in cellular networks[J]. Parallel and Distributed Systems, IEEE Transactions on, 2002,13(9):898-910.
[105]Ormond O, Murphy J, Muntean G-M. Utility-based intelligent network selection in beyond 3G systems:proceedings of the Communications,2006 ICC'06 IEEE International Conference on, 2006[C]. IEEE.
[106]王莹,张平.无线资源管理[M].北京邮电大学出版社,2005.
[107]Yu F, Krishnamurthy V. Optimal joint session admission control in integrated WLAN and CDMA cellular networks with vertical handoff[J]. Mobile Computing, IEEE Transactions on, 2007,6(1):126-139.
[108]Haung Y-R, Ho J-M. Distributed call admission control for a heterogeneous PCS network[J]. Computers, IEEE Transactions on,2002,51(12):1400-1409.
[109]Namal S, Ghaboosi K, Bennis M, MacKenzie AB, Latva-aho M. Joint admission control& interference avoidance in self-organized femtocells:proceedings of the Signals, Systems and Computers (ASILOMAR),2010 Conference Record of the Forty Fourth Asilomar Conference on, 2010[C]. IEEE.
[110]Ngo DT, Le LB, Le-Ngoc T, Hossain E, Kim DI. Distributed interference management in femtocell networks:proceedings of the Vehicular Technology Conference (VTC Fall),2011 IEEE, 2011[C]. IEEE.
[111]Li X, Qian L, Kataria D. Downlink power control in co-channel macrocell femtocell overlay: proceedings of the Information Sciences and Systems,2009 CISS 2009 43rd Annual Conference on,2009[C]. IEEE.
[112]Moon J-M, Cho D-H. Novel handoff decision algorithm in hierarchical macro/femto-cell networks:proceedings of the Wireless Communications and Networking Conference (WCNC), 2010 IEEE,2010[C]. IEEE.
[113]Shaohong W, Xin Z, Ruiming Z, Zhiwei Y, Yinglong F, Dacheng Y. Handover study concerning mobility in the two-hierarchy network:proceedings of the Vehicular Technology Conference,2009 VTC Spring 2009 IEEE 69th,2009[C]. IEEE.
[114]Zhang J, Chan HC, Leung VC. WLC14-6:A Location-Based Vertical Handoff Decision Algorithm for Heterogeneous Mobile Networks:proceedings of the Global Telecommunications Conference,2006 GLOBECOM'06 IEEE,2006[C]. IEEE.
[115]Sun C, Stevens-Navarro E, Wong VW. A constrained MDP-based vertical handoff decision algorithm for 4G wireless networks:proceedings of the Communications,2008 ICC'08 IEEE International Conference on,2008 [C]. IEEE.
[116]Puterman ML. Markov decision processes:discrete stochastic dynamic programming[M], Wiley-Interscience,2009.
[117]White D. Markov decision processes[M]. IMA,1993.
[118]Song W, Zhuang W. QoS provisioning via admission control in cellular/wireless LAN interworking:proceedings of the Broadband Networks,2005 BroadNets 2005 2nd International Conference on,2005[C]. IEEE.
[119]Song W, Jiang H, Zhuang W, Saleh A. Call admission control for integrated voice/data services in cellular/WLAN interworking:proceedings of the Communications,2006 ICC'06 IEEE International Conference on,2006[C]. IEEE.
[120]Chan H, Fan P, Cao Z. A utility-based network selection scheme for multiple services in heterogeneous networks:proceedings of the Wireless Networks, Communications and Mobile Computing,2005 International Conference on,2005[C]. IEEE.
[121]Chen Y-H, Chang C-J, Huang CY. Fuzzy Q-learaing admission control for WCDMA/WLAN heterogeneous networks with multimedia traffic[J]. Mobile Computing, IEEE Transactions on,2009,8(11):1469-1479.
[122]Zhang W. Algorithms for partially observable Markov decision processes[D]:Citeseer, 2001.
[123]White III CC. A survey of solution techniques for the partially observed Markov decision process[J]. Annals of Operations Research,1991,32(1):215-230.
[124]Smallwood RD, Sondik EJ. The optimal control of partially observable Markov processes over a finite horizon[J]. Operations Research,1973,21(5):1071-1088.
[125]Liang B, Haas ZJ. Predictive distance-based mobility management for multidimensional PCS networks[J]. Networking, IEEE/ACM Transactions on,2003,11(5):718-732.
[126]奚宏生.随机过程[M].中国科学技术大学出版社,2009.
[127]Chen Y, Zhang S, Xu S, Li GY. Fundamental trade-offs on green wireless networks[J]. Communications Magazine, IEEE,2011,49(6):30-37.
[128]Fehske A, Fettweis G, Malmodin J, Biczok G. The Global Carbon Footprint of Mobile Communications-The Ecological and Economic Perspective[J]. Communications Magazine, IEEE, 2011,49(8):55-62.
[129]Nasser N, Hassanein H. An optimal and fair call admission control policy for seamless handoff in multimedia wireless networks with QoS guarantees:proceedings of the Global Telecommunications Conference,2004 GLOBECOM'04 IEEE,2004[C]. IEEE.
[130]Le LB, Hoang DT, Niyato D, Hossain E, Kim DI. Joint load balancing and admission control in OFDMA-based femtocell networks:proceedings of the Communications (ICC),2012 IEEE International Conference on,2012[C]. IEEE.
[131]Chen H, Cheng C-C, Yeh H-H. Guard-channel-based incremental and dynamic optimization on call admission control for next-generation qos-aware heterogeneous systems[J]. Vehicular Technology, IEEE Transactions on,2008,57(5):3064-3082.
[132]Bertsekas DP. Dynamic programming and optimal control[M]. Athena Scientific Belmont, 1995.
[133]Tijms HC. Stochastic Modeling and Analysis:A Computational Approach[M]. John Wiley and Sons,1986.
[134]Auer G, Blume O, Giannini V. D2.3:Energy Efficiency Analysis of the Reference Systems, Areas of Improvements and Target Breakdown:proceedings of the INFSO-ICT-247733 EARTH (Energy Aware Radio and NeTwork TecHnologies),2010[C].
[135]Niu Z. TANGO:traffic-aware network planning and green operation[J]. Wireless Communications, IEEE,2011,18(5):25-29.
[136]Auer G, Giannini V, Desset C, Godor I, Skillermark P, Olsson M, Imran MA, Sabella D, Gonzalez MJ, Blume O. How much energy is needed to run a wireless network?[J]. Wireless Communications, IEEE,2011,18(5):40-49.