移动卫星通信网络切换技术研究
摘要
切换技术作为移动卫星通信网络的一项关键技术,实现在通信进行过程中允许用户终端移动、在恶劣的无线传输条件下恢复并保持通信、平衡网络的业务负荷等功能。用户终端的移动性对切换性能有重要影响,本文重点对地面静止终端和高动态终端在移动卫星通信网络中的切换技术进行了研究。
首先,基于STK软件进行建模,仿真分析了用户终端在低轨卫星通信网络和同步轨道卫星通信网络中的可视性。终端类型包括地面静止终端以及航天器、低空高速飞行器、LEO卫星等高动态终端。其次,针对地面静止终端在低轨卫星网络中的切换的场景,在综合考虑接收信号的信噪比和卫星负荷这两个因素的基础上,分别提出了负荷和信噪比加权策略、改进的最小负荷策略。再次,对高动态终端在同构卫星网络中的切换技术进行了研究。设计了核心信令保护机制的精简切换信令流程,定义了三种切换定时器。最后,对高动态终端在异构网络中的切换技术进行了研究。以一种统一的方式设计了从临近空间平台切换到卫星网络的媒介独立切换协议栈参考模型,给出了高动态终端发起的切换信令流程。
通过OPNET仿真验证,负荷和信噪比加权策略的阻塞率低于改进的最小负荷策略,后者的掉话率最低,但切换请求到达率较高,网络的信令负荷较大;核心信令保护机制的切换信令流程可以优化高误码、长时延的通信传输环境下的切换性能。
A key technology of the mobile satellite communication networks is handover, which implements functions such as allowing user terminal move during the communication process, recovering and holding communication in the bad wireless transmission condition, avoiding interrupt between user terminal and the network, balancing traffic load in the network, etc. For the mobility of the user terminal has an important affect on handover performance, the thesis mainly researches on handover technology about stationary terminal on the earth and high dynamic terminal in the mobile satellite communication networks.
Firstly, the visibility of user terminals in the low earth orbit and geosynchronous orbit satellite communication networks has been analyzed. There are different kinds of terminals, that is, stationary terminal on the earth, and three kinds of high dynamic terminals which are space aerocraft, low altitude aerocraft, low earth orbit satellite.
Secondly, integrating the SNR of the received signal with the load of the satellite, load & SNR plus scheme and improved minimum load scheme have been proposed for the handover scene about the stationary terminal on the earth in the low earth orbit satellite network.
Thirdly, the handover technology about high dynamic terminal in the satellite network has been researched, a key signaling protected and condense handover signaling procedure has been designed and three kinds of handover timers have been defined. Finally, the handover technology about high dynamic terminal in the heterogeneous network has been researched; a media independent handover protocol stack from near space platform station to satellite network has been designed in a uniform way. Besides, high dynamic terminal motivated handover procedure in the heterogeneous network from near space platform station to GEO satellite has been given.
OPNET simulation results prove that the two proposed handover schemes can optimize the handover performance for the handover scene about the stationary terminal on the earth in the low earth orbit satellite network; the key signaling protected handover procedure designed can optimize the handover performance in high bit error rate and long delay space transmission environment.
首先,基于STK软件进行建模,仿真分析了用户终端在低轨卫星通信网络和同步轨道卫星通信网络中的可视性。终端类型包括地面静止终端以及航天器、低空高速飞行器、LEO卫星等高动态终端。其次,针对地面静止终端在低轨卫星网络中的切换的场景,在综合考虑接收信号的信噪比和卫星负荷这两个因素的基础上,分别提出了负荷和信噪比加权策略、改进的最小负荷策略。再次,对高动态终端在同构卫星网络中的切换技术进行了研究。设计了核心信令保护机制的精简切换信令流程,定义了三种切换定时器。最后,对高动态终端在异构网络中的切换技术进行了研究。以一种统一的方式设计了从临近空间平台切换到卫星网络的媒介独立切换协议栈参考模型,给出了高动态终端发起的切换信令流程。
通过OPNET仿真验证,负荷和信噪比加权策略的阻塞率低于改进的最小负荷策略,后者的掉话率最低,但切换请求到达率较高,网络的信令负荷较大;核心信令保护机制的切换信令流程可以优化高误码、长时延的通信传输环境下的切换性能。
A key technology of the mobile satellite communication networks is handover, which implements functions such as allowing user terminal move during the communication process, recovering and holding communication in the bad wireless transmission condition, avoiding interrupt between user terminal and the network, balancing traffic load in the network, etc. For the mobility of the user terminal has an important affect on handover performance, the thesis mainly researches on handover technology about stationary terminal on the earth and high dynamic terminal in the mobile satellite communication networks.
Firstly, the visibility of user terminals in the low earth orbit and geosynchronous orbit satellite communication networks has been analyzed. There are different kinds of terminals, that is, stationary terminal on the earth, and three kinds of high dynamic terminals which are space aerocraft, low altitude aerocraft, low earth orbit satellite.
Secondly, integrating the SNR of the received signal with the load of the satellite, load & SNR plus scheme and improved minimum load scheme have been proposed for the handover scene about the stationary terminal on the earth in the low earth orbit satellite network.
Thirdly, the handover technology about high dynamic terminal in the satellite network has been researched, a key signaling protected and condense handover signaling procedure has been designed and three kinds of handover timers have been defined. Finally, the handover technology about high dynamic terminal in the heterogeneous network has been researched; a media independent handover protocol stack from near space platform station to satellite network has been designed in a uniform way. Besides, high dynamic terminal motivated handover procedure in the heterogeneous network from near space platform station to GEO satellite has been given.
OPNET simulation results prove that the two proposed handover schemes can optimize the handover performance for the handover scene about the stationary terminal on the earth in the low earth orbit satellite network; the key signaling protected handover procedure designed can optimize the handover performance in high bit error rate and long delay space transmission environment.
引文
[1]王秉钧,王少勇,田宝玉等.现代卫星通信系统.第一版.北京:电子工业出版社,2004. 374 ~ 383.
[2]王秉钧,王少勇.移动卫星通信的现状与发展.天津通信技术. 1997 (1): 10 ~ 20
[3]郑林华,韩方景,聂皞.卫星移动通信原理与应用.北京:国防工业出版社,2000. 4 ~ 7
[4]马刈非.卫星通信网络技术.第一版.北京:国防工业出版社,2003.236~237.
[5] Pulak K Chowdhury,William Ivancic. Handover schemes in space networks: classification and performance comparison. IEEE SMC-IT’06[C].2006.8~15.
[6] BOTTCHER A, WERNER B. Strategies for handover control in low Earth orbit satellite systems[A]. Vehicular Technology Conference, 1994 IEEE 44th[C]. 1994. 1616~1620.
[7] ZHAO W, TAFAROLLI R, EVANS B G. Combined handover algorithm for dynamic satellite constellations[J]. Electronics Letters 1996, 32(7):622~624.
[8] UZUNALIOGLU H, YEN W. Managing connection handover in satellite networks[A]. IEEE Globecom'97[C]. 1997. 1606~1610.
[9] JAMALIPOUR A, CHEN J. Performance study of handoff schemes in broadband ATM mobile satellite networks[A]. ATM 2000, Proceedings of the IEEE Conference on[C]. 2000. 501~508.
[10] GKIZELI M, TAFAZOLLI R, EVANS B. Modeling handover in mobile satellite diversity based systems[A]. IEEE VTC’01 Fall[C].2001. 131~135.
[11] GKIZELI M, TAFAZOLLI R, EVANS B. Performance analysis of handover mechanisms for non-geo satellite diversity based Systems[A]. IEEE GLOBECOM'01[C]. 2001. 2744~2748.
[12] NGUYEN H N, LEPAJA S. Handover management in low earth orbit satellite IP networks[A]. IEEE GLOBECOM '01[C]. 2001.2730~2734.
[13] KREWEL W, MARAL G. Analysis of the impact of handover strategy on the QoS of satellite diversity based communications systems[A]. Processings of the 18th AIAA ISCSS’2000[C]. 2000. 393~403.
[14]李庆,朱立东,吴诗其.低轨卫星通信系统中快速终端的切换技术.通信学报,2006,27(5):120~125.
[15]牛奔,唐睿,林辉. B3G无线异构网络的切换技术研究.电信科学,2007,23(9):49~52.
[16] Yana B, et al., Proposal on Layer 2.5 Framework and Handover Optimization, IEEE P802.21, Nov., 2004.
[17] IEEE P802.21/D05.00,“Draft IEEE Standard for Local and Metropolitan Area Networks: Media Independent Handover Services,”Apr. 2007.
[18] Vivek Gupta, Media Independent Handover Service Draft Technical Requirements, IEEE P802.21, Sept., 2004.
[19] Alan Carlton, et al., Media Independent Handover Functions and Services Specification, IEEE P802.21,Nov., 2004.
[20]汪静,许文韬,王能.异质网络间切换技术研究.通讯和计算机,2006,3(4):48~53.
[21] Reijo Salminen, Unified Trigger Mechanism for Media Independent Handovers, IEEE P802.21, Nov., 2004.
[22] Vivek G. Gupta, David Johnston, A Generalized Model for Link Layer Triggers, IEEE P802.21, Mar., 2004.
[23] Vivek Gupta, IEEE 802.21 Proposals for Media Independent Handovers, IEEE P802.21, Nov., 2004.
[24] Wonseok Lee, Mun-Seok Kang, and Mi-Sook Lim. Implementation of 802.21 for Seamless Handover Across Heterogeneous Networks. APNOMS 2007, LNCS 4773, 2007.326~333.
[25] Lampropoulos, G. Salkintzis, A.K. Passas, N. Media-Independent Handover for Seamless Service Provision in Heterogeneous Networks. IEEE. 2008. 64~71.
[26]罗文辉.一种新的无线接入标准——UMA.中国科技信息,2005,(24A):66~67.
[27]王祥勃.网络融合中的UMA解决方案.移动通信.2007,31(5): 36~38.
[28]彭小平.下一代移动技术UMA探讨.通信技术.2007,9(40): 36~38.
[29]郭正非,须德,韩升.UMA方式实现固网与蜂窝网络融合的研究.计算机技术与发展.2006,16(3):226~228
[30]金镝,孙姬.异构无线网络间的无缝移动技术.电信网技术,2007,10(10):12~16
[31]张彩娟. STK及其在卫星系统仿真中的应用.无线电通信技术,2007,33(4):45~46
[32] Mischa Schwartz.移动无线通信.第一版.许希斌,李云州译.北京:电子工业出版社,2006.194~195
[33] Hong, D. and S. S. Rappaport. Traffic model and performance analysis for cellular mobile radio telephone systems with prioritized and non-prioritized handoff procedures. IEEE Transactions on Vehicular Technology, VT-35, 1999,3(August), 77~92.
[34]王彦广,李健全,李勇,姚伟.近空间飞行器的特点及其应用前景.航天器工程,2007,16(1):50~57.
[35]赵炜渝,邢宁.近太空平台及其军事应用.国际太空,2006,(5):24~28.
[36]曹秀云.近空间飞行器成为各国近期研究的热点.中国航天,2006,(6):32~35.
[37]曹秀云.国外加紧研究临近空间飞行器.国防,2007,(5):69~73.
[38]何彦峰.浅析临近空间平台的军事应用.国防科技,2007,(6):32~35.
[39] Ali-Yahiya, T. Sethom, K. Pujolle, G. A Case Study: IEEE 802.21 Framework Design for Service Continuity across WLAN and WMAN. Wireless and Optical Communications Networks, WOCN '07. 2007.1~5.
[40] Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia;Services and Architectures, ETSI TR 101 984, November 2002.
[41] Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia (BSM); Common air interface specification; Satellite Independent Service Access Point (SI-SAP), ETSI TS 102 357, May 2005.
[42] Qureshi, R., Dadej, A. Adding Support for Satellite Interfaces to 802.21 Media Independent Handover.542~546. 15th IEEE International Conference on Networks, ICON 2007. 2007. 542-546
[2]王秉钧,王少勇.移动卫星通信的现状与发展.天津通信技术. 1997 (1): 10 ~ 20
[3]郑林华,韩方景,聂皞.卫星移动通信原理与应用.北京:国防工业出版社,2000. 4 ~ 7
[4]马刈非.卫星通信网络技术.第一版.北京:国防工业出版社,2003.236~237.
[5] Pulak K Chowdhury,William Ivancic. Handover schemes in space networks: classification and performance comparison. IEEE SMC-IT’06[C].2006.8~15.
[6] BOTTCHER A, WERNER B. Strategies for handover control in low Earth orbit satellite systems[A]. Vehicular Technology Conference, 1994 IEEE 44th[C]. 1994. 1616~1620.
[7] ZHAO W, TAFAROLLI R, EVANS B G. Combined handover algorithm for dynamic satellite constellations[J]. Electronics Letters 1996, 32(7):622~624.
[8] UZUNALIOGLU H, YEN W. Managing connection handover in satellite networks[A]. IEEE Globecom'97[C]. 1997. 1606~1610.
[9] JAMALIPOUR A, CHEN J. Performance study of handoff schemes in broadband ATM mobile satellite networks[A]. ATM 2000, Proceedings of the IEEE Conference on[C]. 2000. 501~508.
[10] GKIZELI M, TAFAZOLLI R, EVANS B. Modeling handover in mobile satellite diversity based systems[A]. IEEE VTC’01 Fall[C].2001. 131~135.
[11] GKIZELI M, TAFAZOLLI R, EVANS B. Performance analysis of handover mechanisms for non-geo satellite diversity based Systems[A]. IEEE GLOBECOM'01[C]. 2001. 2744~2748.
[12] NGUYEN H N, LEPAJA S. Handover management in low earth orbit satellite IP networks[A]. IEEE GLOBECOM '01[C]. 2001.2730~2734.
[13] KREWEL W, MARAL G. Analysis of the impact of handover strategy on the QoS of satellite diversity based communications systems[A]. Processings of the 18th AIAA ISCSS’2000[C]. 2000. 393~403.
[14]李庆,朱立东,吴诗其.低轨卫星通信系统中快速终端的切换技术.通信学报,2006,27(5):120~125.
[15]牛奔,唐睿,林辉. B3G无线异构网络的切换技术研究.电信科学,2007,23(9):49~52.
[16] Yana B, et al., Proposal on Layer 2.5 Framework and Handover Optimization, IEEE P802.21, Nov., 2004.
[17] IEEE P802.21/D05.00,“Draft IEEE Standard for Local and Metropolitan Area Networks: Media Independent Handover Services,”Apr. 2007.
[18] Vivek Gupta, Media Independent Handover Service Draft Technical Requirements, IEEE P802.21, Sept., 2004.
[19] Alan Carlton, et al., Media Independent Handover Functions and Services Specification, IEEE P802.21,Nov., 2004.
[20]汪静,许文韬,王能.异质网络间切换技术研究.通讯和计算机,2006,3(4):48~53.
[21] Reijo Salminen, Unified Trigger Mechanism for Media Independent Handovers, IEEE P802.21, Nov., 2004.
[22] Vivek G. Gupta, David Johnston, A Generalized Model for Link Layer Triggers, IEEE P802.21, Mar., 2004.
[23] Vivek Gupta, IEEE 802.21 Proposals for Media Independent Handovers, IEEE P802.21, Nov., 2004.
[24] Wonseok Lee, Mun-Seok Kang, and Mi-Sook Lim. Implementation of 802.21 for Seamless Handover Across Heterogeneous Networks. APNOMS 2007, LNCS 4773, 2007.326~333.
[25] Lampropoulos, G. Salkintzis, A.K. Passas, N. Media-Independent Handover for Seamless Service Provision in Heterogeneous Networks. IEEE. 2008. 64~71.
[26]罗文辉.一种新的无线接入标准——UMA.中国科技信息,2005,(24A):66~67.
[27]王祥勃.网络融合中的UMA解决方案.移动通信.2007,31(5): 36~38.
[28]彭小平.下一代移动技术UMA探讨.通信技术.2007,9(40): 36~38.
[29]郭正非,须德,韩升.UMA方式实现固网与蜂窝网络融合的研究.计算机技术与发展.2006,16(3):226~228
[30]金镝,孙姬.异构无线网络间的无缝移动技术.电信网技术,2007,10(10):12~16
[31]张彩娟. STK及其在卫星系统仿真中的应用.无线电通信技术,2007,33(4):45~46
[32] Mischa Schwartz.移动无线通信.第一版.许希斌,李云州译.北京:电子工业出版社,2006.194~195
[33] Hong, D. and S. S. Rappaport. Traffic model and performance analysis for cellular mobile radio telephone systems with prioritized and non-prioritized handoff procedures. IEEE Transactions on Vehicular Technology, VT-35, 1999,3(August), 77~92.
[34]王彦广,李健全,李勇,姚伟.近空间飞行器的特点及其应用前景.航天器工程,2007,16(1):50~57.
[35]赵炜渝,邢宁.近太空平台及其军事应用.国际太空,2006,(5):24~28.
[36]曹秀云.近空间飞行器成为各国近期研究的热点.中国航天,2006,(6):32~35.
[37]曹秀云.国外加紧研究临近空间飞行器.国防,2007,(5):69~73.
[38]何彦峰.浅析临近空间平台的军事应用.国防科技,2007,(6):32~35.
[39] Ali-Yahiya, T. Sethom, K. Pujolle, G. A Case Study: IEEE 802.21 Framework Design for Service Continuity across WLAN and WMAN. Wireless and Optical Communications Networks, WOCN '07. 2007.1~5.
[40] Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia;Services and Architectures, ETSI TR 101 984, November 2002.
[41] Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia (BSM); Common air interface specification; Satellite Independent Service Access Point (SI-SAP), ETSI TS 102 357, May 2005.
[42] Qureshi, R., Dadej, A. Adding Support for Satellite Interfaces to 802.21 Media Independent Handover.542~546. 15th IEEE International Conference on Networks, ICON 2007. 2007. 542-546