Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.110
Jian Li, Xiaoqiang Ji, Xue Liu, Jianguo Yao, S. Gopalakrishnan, F. Hu
We address the issue of supporting real-time message dissemination in a publish/subscribe system. The asynchronous operation and connection brokering approach embodied in the publish/subscribe paradigm aid scalability and support varied topologies. These advantages, however, create challenges for providing predictable performance for real-time applications. We propose an efficient design for message queuing and forwarding by brokers in a publish/subscribe system. We differentiate messages by topics and not just be publishers or subscribers. Our real-time publish/subscribe design is analogous to the design of packet routers for high-speed networks. We manage input and output message queues per-client and per-topic. This approach facilitates a multiple-input multiple-output architecture and provides performance isolation for different topics. This approach differs from conventional system architectures that either use first-in first-out ordering of messages or employ per-client (not per-topic) prioritization. Our framework can provide deterministic upper bounds on delay for periodic and general (σ; ρ)-bounded real-time message flow in a publish/subscribe system with low overhead.
{"title":"Topic-based resource allocation for real-time publish/subscribe communication systems","authors":"Jian Li, Xiaoqiang Ji, Xue Liu, Jianguo Yao, S. Gopalakrishnan, F. Hu","doi":"10.4108/CHINACOM.2010.110","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.110","url":null,"abstract":"We address the issue of supporting real-time message dissemination in a publish/subscribe system. The asynchronous operation and connection brokering approach embodied in the publish/subscribe paradigm aid scalability and support varied topologies. These advantages, however, create challenges for providing predictable performance for real-time applications. We propose an efficient design for message queuing and forwarding by brokers in a publish/subscribe system. We differentiate messages by topics and not just be publishers or subscribers. Our real-time publish/subscribe design is analogous to the design of packet routers for high-speed networks. We manage input and output message queues per-client and per-topic. This approach facilitates a multiple-input multiple-output architecture and provides performance isolation for different topics. This approach differs from conventional system architectures that either use first-in first-out ordering of messages or employ per-client (not per-topic) prioritization. Our framework can provide deterministic upper bounds on delay for periodic and general (σ; ρ)-bounded real-time message flow in a publish/subscribe system with low overhead.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115042555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.135
Shenli Zhang, Bin Chen, Linghao Cheng, Zhaohui Li, Chao Lu, Hui Wang
In current optical coherent communication systems, balanced photo-detectors are typically employed, which preserve the product of the received optical signals and the local oscillators (LO) for detection but cancel out the power of both. Since only the product of the received optical signals and the LO is used to estimate the transmitted complex symbol, such detection scheme is suboptimal due to the loss of some useful information embedded in the transmitted signal power. Different from that, this paper proposes a new detection scheme which maintains full information obtained from the photo-detectors. Specifically, we first extract the transmitted signal power from the output of the photo-detector. After that, we use not only the product of the signals and the LO but also the power of signals to estimate the target signals. For 16-qudrature-amplitude-modulation (16-QAM) and 64-QAM signals, the simulation results show that our new scheme can outperform the conventional ones by more than 1 dB.
{"title":"Enhancing the coherent detection of optical QAM signals by exploiting the information of received optical power","authors":"Shenli Zhang, Bin Chen, Linghao Cheng, Zhaohui Li, Chao Lu, Hui Wang","doi":"10.4108/CHINACOM.2010.135","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.135","url":null,"abstract":"In current optical coherent communication systems, balanced photo-detectors are typically employed, which preserve the product of the received optical signals and the local oscillators (LO) for detection but cancel out the power of both. Since only the product of the received optical signals and the LO is used to estimate the transmitted complex symbol, such detection scheme is suboptimal due to the loss of some useful information embedded in the transmitted signal power. Different from that, this paper proposes a new detection scheme which maintains full information obtained from the photo-detectors. Specifically, we first extract the transmitted signal power from the output of the photo-detector. After that, we use not only the product of the signals and the LO but also the power of signals to estimate the target signals. For 16-qudrature-amplitude-modulation (16-QAM) and 64-QAM signals, the simulation results show that our new scheme can outperform the conventional ones by more than 1 dB.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117167986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.137
Weigang Hou, Lei Guo, Xingwei Wang
In recent years, as the increasing effect of greenhouse and extremely consumption of worldwide energy, port-cost and energy-consumption savings are becoming a dual of new objectives of further developing an optical network. Using hybrid technology to replace Optical-Electrical-Optical (OEO) fabric with an all optical (OOO) one to save more consumed energy and using hierarchical technology to aggregate several wavelengths into wavebands to perform port-cost savings is an attractive solution for next-generation optical networks. In this paper, we jointly consider port-cost and energy-consumption in hybrid hierarchical optical network and develop efficient approaches ranging from Integer Linear Programming (ILP) models to heuristics. Simulation results of two heuristic approaches show that, the cost of Transmitting Ports (TPs) used in OOO switch is contrary to the energy consumed by OEO part of hybrid hierarchical Optical Cross Connect (OXC) node, and it is necessary to make a new design to obtain satisfactory trade-off performance.
{"title":"Energy efficient algorithm with considering port-cost in hybrid hierarchical optical networks","authors":"Weigang Hou, Lei Guo, Xingwei Wang","doi":"10.4108/CHINACOM.2010.137","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.137","url":null,"abstract":"In recent years, as the increasing effect of greenhouse and extremely consumption of worldwide energy, port-cost and energy-consumption savings are becoming a dual of new objectives of further developing an optical network. Using hybrid technology to replace Optical-Electrical-Optical (OEO) fabric with an all optical (OOO) one to save more consumed energy and using hierarchical technology to aggregate several wavelengths into wavebands to perform port-cost savings is an attractive solution for next-generation optical networks. In this paper, we jointly consider port-cost and energy-consumption in hybrid hierarchical optical network and develop efficient approaches ranging from Integer Linear Programming (ILP) models to heuristics. Simulation results of two heuristic approaches show that, the cost of Transmitting Ports (TPs) used in OOO switch is contrary to the energy consumed by OEO part of hybrid hierarchical Optical Cross Connect (OXC) node, and it is necessary to make a new design to obtain satisfactory trade-off performance.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115246210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Iterative probabilistic decoding of binary low-density parity-check (LDPC) codes have been studied extensively. Non-binary LDPC codes have recently attracted an increasing attention. Most of the existing non-binary codes are built over GF(2q), and decoding methods developed for binary LDPC codes cannot be used directly with multilevel modulations. In this paper, we first extend the binary parity-check codes to the case with multiple symbols over modular arithmetic. Then, we develop a sum-product algorithm to decode this new type of codes at the symbol level. Finally, we propose an effective constellation mapping method for multilevel modulations. Error performances of this type of codes with 4-PAM, 4-PSK, and 16-PSK modulations over AWGN channels are provided. Compared with uncoded systems, the coding gain of a medium-size regular LDPC code of rate 8/9 with 4-PAM and 4-PSK modulations is about 5 dB. With 16-PSK and an appropriate constellation mapping at a code rate 3/4, the proposed code's performance is comparable to that of trellis codes.
{"title":"Iterative symbol-by-symbol decoding of LDPC codes and constellation mapping for multilevel modulation","authors":"Hongtao Jiang, Zhongfeng Wang, Huaping Liu","doi":"10.4108/CHINACOM.2010.7","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.7","url":null,"abstract":"Iterative probabilistic decoding of binary low-density parity-check (LDPC) codes have been studied extensively. Non-binary LDPC codes have recently attracted an increasing attention. Most of the existing non-binary codes are built over GF(2q), and decoding methods developed for binary LDPC codes cannot be used directly with multilevel modulations. In this paper, we first extend the binary parity-check codes to the case with multiple symbols over modular arithmetic. Then, we develop a sum-product algorithm to decode this new type of codes at the symbol level. Finally, we propose an effective constellation mapping method for multilevel modulations. Error performances of this type of codes with 4-PAM, 4-PSK, and 16-PSK modulations over AWGN channels are provided. Compared with uncoded systems, the coding gain of a medium-size regular LDPC code of rate 8/9 with 4-PAM and 4-PSK modulations is about 5 dB. With 16-PSK and an appropriate constellation mapping at a code rate 3/4, the proposed code's performance is comparable to that of trellis codes.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123242362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.20
Jie Zhao, Stephen Culver, M. Gidlund
Ultra-wideband (UWB) communication is currently considered as a key technology of the next generation wireless personal area network (WPAN) and wireless local area network (WLAN). UWB operation do not require a spectrum license but UWB devices are required to share spectrum with licensed narrow band users. This paper presents a novel system for direct sequence (DS) UWB and the proposed dynamic bandwidth direct sequence (DBDS) system focuses on exploring a new idea rather than concentrating on impulse manipulation, provides a cognitive solution for DS-based UWB in a much simpler and more efficient way. The proposed system is able to transfer data under a fraction of original spread spectrum signal bandwidth and different spectral shapes while maintaining the same data rate. The system does not require generating specific impulse for working environment, therefore significantly reduces the system complexity. Simulation results demonstrate that the DBDS has a very exciting performance. Even received with different bandwidths and different spectral shapes, the data information can still be fully recovered at the same data rate.
{"title":"Performance of UWB communication based on dynamic bandwidth direct sequence","authors":"Jie Zhao, Stephen Culver, M. Gidlund","doi":"10.4108/CHINACOM.2010.20","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.20","url":null,"abstract":"Ultra-wideband (UWB) communication is currently considered as a key technology of the next generation wireless personal area network (WPAN) and wireless local area network (WLAN). UWB operation do not require a spectrum license but UWB devices are required to share spectrum with licensed narrow band users. This paper presents a novel system for direct sequence (DS) UWB and the proposed dynamic bandwidth direct sequence (DBDS) system focuses on exploring a new idea rather than concentrating on impulse manipulation, provides a cognitive solution for DS-based UWB in a much simpler and more efficient way. The proposed system is able to transfer data under a fraction of original spread spectrum signal bandwidth and different spectral shapes while maintaining the same data rate. The system does not require generating specific impulse for working environment, therefore significantly reduces the system complexity. Simulation results demonstrate that the DBDS has a very exciting performance. Even received with different bandwidths and different spectral shapes, the data information can still be fully recovered at the same data rate.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123333259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.48
Zhixiong Liang, Xingcheng Liu
Many applications of Wireless Sensor Networks (WSNs) require sensor nodes know their positions. Equipping GPS modules can solve this problem easily, but it is of high cost. In this paper, we propose a centralized localization algorithm for WSN based on mesh relaxation method. Computer simulations show that with our algorithm the positions of nodes can be estimated in a relative coordinate system, which can be transformed to the global coordinate system with the aid of a few anchor nodes. The proposed algorithm can avoid folds and flips through firstly stretching the mesh of the network by pulling some fringe nodes towards different directions, and then making the mesh to shrink by relaxing it. The position results achieved have higher precision than those with other positioning methods. Our algorithm can be used based on ranging or connectivity.
{"title":"A centralized localization algorithm based on mesh relaxation in Wireless Sensor Networks","authors":"Zhixiong Liang, Xingcheng Liu","doi":"10.4108/CHINACOM.2010.48","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.48","url":null,"abstract":"Many applications of Wireless Sensor Networks (WSNs) require sensor nodes know their positions. Equipping GPS modules can solve this problem easily, but it is of high cost. In this paper, we propose a centralized localization algorithm for WSN based on mesh relaxation method. Computer simulations show that with our algorithm the positions of nodes can be estimated in a relative coordinate system, which can be transformed to the global coordinate system with the aid of a few anchor nodes. The proposed algorithm can avoid folds and flips through firstly stretching the mesh of the network by pulling some fringe nodes towards different directions, and then making the mesh to shrink by relaxing it. The position results achieved have higher precision than those with other positioning methods. Our algorithm can be used based on ranging or connectivity.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123934608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.24
Yun Li, Zhun Wang, X. You, Qilie Liu, M. Daneshmand
Reliable transmission in Intermittently Connected Mobile Networks (ICMNs) is a challenging work because the effective and reliable connection between the source and destination can not be sustained in ICMNs. To reliably hand over data to the destination, many dissemination-based routing protocols are proposed. Dissemination-based routing protocols assure nodes including intermediate nodes and destinations have more chances to receive packets, which will increase the probability that the packets can be correctly received by the destination. However, the existing error recovery mechanisms in network layer use the simple CRC to check the data packets independently, and discard the error packets even if one correct packet can be obtained from more than one partly error packet. In this paper, we propose a novel Network layer Error Recovery method based on FEC, named NER. NER divides a data packet into RS blocks and insert redundancy to each block. So the intermediate nodes and destinations can recover a correct data packet from multiple partially error copies of the same packet. The simulation results show that NER can obviously increase the delivery-ratio in ICMNs.
{"title":"Error recovery based on FEC in network-layer for Intermittently Connected Mobile Networks","authors":"Yun Li, Zhun Wang, X. You, Qilie Liu, M. Daneshmand","doi":"10.4108/CHINACOM.2010.24","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.24","url":null,"abstract":"Reliable transmission in Intermittently Connected Mobile Networks (ICMNs) is a challenging work because the effective and reliable connection between the source and destination can not be sustained in ICMNs. To reliably hand over data to the destination, many dissemination-based routing protocols are proposed. Dissemination-based routing protocols assure nodes including intermediate nodes and destinations have more chances to receive packets, which will increase the probability that the packets can be correctly received by the destination. However, the existing error recovery mechanisms in network layer use the simple CRC to check the data packets independently, and discard the error packets even if one correct packet can be obtained from more than one partly error packet. In this paper, we propose a novel Network layer Error Recovery method based on FEC, named NER. NER divides a data packet into RS blocks and insert redundancy to each block. So the intermediate nodes and destinations can recover a correct data packet from multiple partially error copies of the same packet. The simulation results show that NER can obviously increase the delivery-ratio in ICMNs.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129771780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.4108/CHINACOM.2010.53
Xiao Wang, Zhifeng Zhao, Ning Zhao, Honggang Zhang
Compressed sensing (CS) is an emerging theory based on the fact that the salient information of a signal can be preserved in a relatively small number of linear projections. Compressed sensing has been well used in the area of image compression and signal processing in the past few years. Recently, compressed sensing has been earning ever-increasing interests in the area of wireless communication networks. According to its advantageous characteristics, compressed sensing is able to play significant role in the fields like wireless channel estimation, signal detection, data gathering, network monitoring, and so on. This study describes current researches on the applications of compressed sensing in wireless communication networks, and then enumerates burning questions and the master keys of their corresponding solutions in these fields. Accordingly, we first introduce the basic approach of compressed sensing, and then summarize recent technical advancements of compressed sensing schemes and their applications in wireless communication networks. We assort these techniques according to the general OSI (Interconnection Reference Model) network model. In the end, we analyze problems and potential applications of compressed sensing, including novel methods for efficient data gathering by executing compressed sensing with random routing in wireless sensor networking environment.
{"title":"On the application of compressed sensing in communication networks","authors":"Xiao Wang, Zhifeng Zhao, Ning Zhao, Honggang Zhang","doi":"10.4108/CHINACOM.2010.53","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.53","url":null,"abstract":"Compressed sensing (CS) is an emerging theory based on the fact that the salient information of a signal can be preserved in a relatively small number of linear projections. Compressed sensing has been well used in the area of image compression and signal processing in the past few years. Recently, compressed sensing has been earning ever-increasing interests in the area of wireless communication networks. According to its advantageous characteristics, compressed sensing is able to play significant role in the fields like wireless channel estimation, signal detection, data gathering, network monitoring, and so on. This study describes current researches on the applications of compressed sensing in wireless communication networks, and then enumerates burning questions and the master keys of their corresponding solutions in these fields. Accordingly, we first introduce the basic approach of compressed sensing, and then summarize recent technical advancements of compressed sensing schemes and their applications in wireless communication networks. We assort these techniques according to the general OSI (Interconnection Reference Model) network model. In the end, we analyze problems and potential applications of compressed sensing, including novel methods for efficient data gathering by executing compressed sensing with random routing in wireless sensor networking environment.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128539299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuxi Liu, Ju Liu, Lina Zheng, Weidong Guo, H. Chen
Joint decoding at the base stations is investigated as a means to improve the uplink/downlink throughput of current cellular systems over fading channels. In this paper, the multi-cell relay-assisted time-division uplink system, i.e. one active user per time slot per cell with a relay serving that user, is studied. A linear mesh network is considered in which a single user per-cell communicates to a local base station via a dedicated relay. Base station cooperation through multi-cell decoding, where each cell has a single relay that amplifies and forwards the desired transmission signals to the base station. All the base stations in the mesh network collaboratively decode the signals received at each. The key contribution of this paper is compare the ergodic sum-rate in single-cell processing with multi-cell processing, under the system model, separately.
{"title":"Inter-cell relaying and base station cooperation in cellular uplink systems","authors":"Yuxi Liu, Ju Liu, Lina Zheng, Weidong Guo, H. Chen","doi":"10.4108/CHINACOM.2010.9","DOIUrl":"https://doi.org/10.4108/CHINACOM.2010.9","url":null,"abstract":"Joint decoding at the base stations is investigated as a means to improve the uplink/downlink throughput of current cellular systems over fading channels. In this paper, the multi-cell relay-assisted time-division uplink system, i.e. one active user per time slot per cell with a relay serving that user, is studied. A linear mesh network is considered in which a single user per-cell communicates to a local base station via a dedicated relay. Base station cooperation through multi-cell decoding, where each cell has a single relay that amplifies and forwards the desired transmission signals to the base station. All the base stations in the mesh network collaboratively decode the signals received at each. The key contribution of this paper is compare the ergodic sum-rate in single-cell processing with multi-cell processing, under the system model, separately.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130571962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ensemble Kalman filter (EnKF) is an efficient algorithm in dealing with nonlinear and discontinuous data assimilation problems. We designed a scheme that integrated the EnKF and Simplified Simple Biosphere model (SSiB) to improve the estimate of land surface temperature and evapotranspiration (ET) using Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) products. This scheme can make a judgment whether there are MODSI LST products available to assimilate at every time step. Then we compared the assimilation results with SSiB open loop simulation and station observations. The results showed that the EnKF algorithm could improve the land surface temperature and evapotranspiration estimate. Then we discussed five challenges during the experiment. In a word, this scheme provides a practical way for improving land surface models estimates with assimilating remote sensing observations.
{"title":"Using ensemble Kalman filter to assimilate land surface temperature and evapotranspiration","authors":"Yang Wang, Yaonan Zhang, Guohui Zhao","doi":"10.4108/ADIM.2010.4","DOIUrl":"https://doi.org/10.4108/ADIM.2010.4","url":null,"abstract":"Ensemble Kalman filter (EnKF) is an efficient algorithm in dealing with nonlinear and discontinuous data assimilation problems. We designed a scheme that integrated the EnKF and Simplified Simple Biosphere model (SSiB) to improve the estimate of land surface temperature and evapotranspiration (ET) using Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) products. This scheme can make a judgment whether there are MODSI LST products available to assimilate at every time step. Then we compared the assimilation results with SSiB open loop simulation and station observations. The results showed that the EnKF algorithm could improve the land surface temperature and evapotranspiration estimate. Then we discussed five challenges during the experiment. In a word, this scheme provides a practical way for improving land surface models estimates with assimilating remote sensing observations.","PeriodicalId":422191,"journal":{"name":"2010 5th International ICST Conference on Communications and Networking in China","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129911820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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