A real-world localization system for wireless sensor networks that adapts for mobility and irregular radio propagation model is considered. The traditional range-based techniques and recent range-free localization sch...A real-world localization system for wireless sensor networks that adapts for mobility and irregular radio propagation model is considered. The traditional range-based techniques and recent range-free localization schemes are not well competent for localization in mobile sensor networks, while the probabilistic approach of Bayesian filtering with particle-based density representations provides a comprehensive solution to such localization problem. Monte Carlo localization is a Bayesian filtering method that approximates the mobile node's location by a set of weighted particles. In this paper, an enhanced Monte Carlo localization algorithm-Extended Monte Carlo Localization (Ext-MCL) is proposed, i.e., the traditional Monte Carlo localization algorithm is improved and extended to make it suitable for the practical wireless network environment where the radio propagation model is irregular. Simulation results show the proposal gets better localization accuracy and higher localizable node number than previously proposed Monte Carlo localization schemes not only for ideal radio model, but also for irregular one.展开更多
Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting ...Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting in substantial energy consumption of networks. A grid-based directed diffusion is presented to improve the energy efficiency of directed diffusion. Virtual geographic grid clusters are constructed by self-organization of nodes using geographic location information. The flooding of interest and exploratory data of original directed diffusion is limited in cluster head nodes. The simulation results and testbed experiments show that the method effectively reduces the network energy consumption. This gain is not achieved at the cost of either delivery ratio or the delay. Importantly, the decreased load also leads to a better delivery ratio and lower delay.展开更多
Efficient broadcasting protocols based on Connected Dominating Set (CDS) are frequently used;hence the entire broadcast domain is restricted to nodes in the CDS. This letter proves that a node must be a CDS node, if i...Efficient broadcasting protocols based on Connected Dominating Set (CDS) are frequently used;hence the entire broadcast domain is restricted to nodes in the CDS. This letter proves that a node must be a CDS node, if its neighbors with larger keys cannot cover it together.Then a simple distributed CDS construction algorithm is proposed, which is more effective than the existing algorithms in reducing the dominating set size and the computation complexity at the same time. Simulation results also confirm this, especially in relatively dense networks.展开更多
Recent research shows using network sion efficiency in wireless networks greatly et for retransmission over composite fading coding for reliable multicast can improve the retransmis- In this paper, we study how to co...Recent research shows using network sion efficiency in wireless networks greatly et for retransmission over composite fading coding for reliable multicast can improve the retransmis- In this paper, we study how to code the composite pack- channels efficiently. For the composite fading environ- ment with muhiple receivers, receivers experience different fading at any time. It＇ s very important to code the composite packet so that intended receivers are in good channel qualities, because in- tended receivers in deep fading have little opportunity to receive the composite packet correctly. Hence, we propose a novel composite packet coding principle of maximizing the total SNR of intend- ed receivers. Since the proposed principle is an NP-complete problem, an efficient heuristic algo- rithm with low complexity is given for finding a suboptimal solution. Simulation results show the heu- ristic based scheme achieves higher transmission efficiency than other network coding-based schemes due to the multi-user diversity gain.展开更多
基金the National Natural Science Foundation of China (No.60671033)the Research Fund for the Doctoral Program of Higher Education (No.20060614015).
文摘A real-world localization system for wireless sensor networks that adapts for mobility and irregular radio propagation model is considered. The traditional range-based techniques and recent range-free localization schemes are not well competent for localization in mobile sensor networks, while the probabilistic approach of Bayesian filtering with particle-based density representations provides a comprehensive solution to such localization problem. Monte Carlo localization is a Bayesian filtering method that approximates the mobile node's location by a set of weighted particles. In this paper, an enhanced Monte Carlo localization algorithm-Extended Monte Carlo Localization (Ext-MCL) is proposed, i.e., the traditional Monte Carlo localization algorithm is improved and extended to make it suitable for the practical wireless network environment where the radio propagation model is irregular. Simulation results show the proposal gets better localization accuracy and higher localizable node number than previously proposed Monte Carlo localization schemes not only for ideal radio model, but also for irregular one.
基金the National High Technology Research and Development Programme of China(No.2002AA142020)the National Natural Science Foundation of China(No.60475012)
文摘Directed diffusion is a data dissemination protocol for wireless sensor networks. In directed diffusion, flooding is used for dissemination of interest and exploratory data, which will bring broadcast storm resulting in substantial energy consumption of networks. A grid-based directed diffusion is presented to improve the energy efficiency of directed diffusion. Virtual geographic grid clusters are constructed by self-organization of nodes using geographic location information. The flooding of interest and exploratory data of original directed diffusion is limited in cluster head nodes. The simulation results and testbed experiments show that the method effectively reduces the network energy consumption. This gain is not achieved at the cost of either delivery ratio or the delay. Importantly, the decreased load also leads to a better delivery ratio and lower delay.
基金Supported by the National Natural Science Foundation of China (No.60202005).
文摘Efficient broadcasting protocols based on Connected Dominating Set (CDS) are frequently used;hence the entire broadcast domain is restricted to nodes in the CDS. This letter proves that a node must be a CDS node, if its neighbors with larger keys cannot cover it together.Then a simple distributed CDS construction algorithm is proposed, which is more effective than the existing algorithms in reducing the dominating set size and the computation complexity at the same time. Simulation results also confirm this, especially in relatively dense networks.
文摘Recent research shows using network sion efficiency in wireless networks greatly et for retransmission over composite fading coding for reliable multicast can improve the retransmis- In this paper, we study how to code the composite pack- channels efficiently. For the composite fading environ- ment with muhiple receivers, receivers experience different fading at any time. It＇ s very important to code the composite packet so that intended receivers are in good channel qualities, because in- tended receivers in deep fading have little opportunity to receive the composite packet correctly. Hence, we propose a novel composite packet coding principle of maximizing the total SNR of intend- ed receivers. Since the proposed principle is an NP-complete problem, an efficient heuristic algo- rithm with low complexity is given for finding a suboptimal solution. Simulation results show the heu- ristic based scheme achieves higher transmission efficiency than other network coding-based schemes due to the multi-user diversity gain.
