A 2.4GHz monolithic CMOS receiver with direct-conversion architecture is presented. This quadrature receiver is designed for 802.11b wireless LAN applications at the maximum data rate of 11Mbps as a low-cost solution....A 2.4GHz monolithic CMOS receiver with direct-conversion architecture is presented. This quadrature receiver is designed for 802.11b wireless LAN applications at the maximum data rate of 11Mbps as a low-cost solution. Five key blocks,i, e., a low noise amplifier (LNA), a down-conversion mixer, a variable gain amplifier, a low pass filter, and a DC- offset cancellation circuit,are designed based on system design and low noise high linearity considerations. The necessary auxiliary circuits are also included. Fabricated in SMIC 0.18μm 1p6m RF CMOS process, the receiver's performance is measured as:4. 1 dB noise figure, - 7.5dBm input third order intercept point (IIP3) for LNA & mixer at high gain setting, - 14dBm IIP3 for the whole receiver,53dBc @30MHz offset of adjacent channel power rejection,and less than 5mV out- put DC-offset. The receiver consumes 44mA under a 1.8V power supply with I,Q two paths.展开更多
In this paper, the security technology of ad hoc networks is studied.To improve the previous multi-receiver signcryption schemes, an ID-based multi-message and multi-receiver signcryption scheme for rekeying in ad hoc...In this paper, the security technology of ad hoc networks is studied.To improve the previous multi-receiver signcryption schemes, an ID-based multi-message and multi-receiver signcryption scheme for rekeying in ad hoc networks is proposed.In this scheme, a sender can simultaneously signcrypt n messeges for n receivers, and a receiver can unsigncrypt the ciphertext to get his message with his own private key.An analysis of this scheme indicates that it achieves authenticity and confidentiality in the random oracle model while being of lower computation and communication overhead.Finally, for the application of our scheme in ad hoc, a threshold key updating protocol for ad hoc networks is given.展开更多
With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminat...With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminate these deficiencies, adopts two basic mechanisms: (1) Bandwidth Estimation and (2) Immediate Recovery. Bandwidth estimation is carried out at the receiver, and the result is sent back to the sender via the acknowledgments. Immediate Recovery guarantees high performance even in lossy link. Rab can distinguish the reason for packet loss, and thus adopt appropriate recovery strategy. For loss by network congestion, it will back off its congestion window, and for loss by link errors, it will recover the congestion window immediately. Simulations indicated that Rab has superiority over other TCP implementations.展开更多
We present a scheme for remotely preparing a state via the controls of many agents in a network.In thescheme,the agents' controls are achieved by utilizing quantum key distribution.Generally,the original state can...We present a scheme for remotely preparing a state via the controls of many agents in a network.In thescheme,the agents' controls are achieved by utilizing quantum key distribution.Generally,the original state can berestored by the receiver with probability 1/2 if all the agents collaborate.However,for certain type of original states therestoration probability is unit.展开更多
In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving ...In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving scheme for the sink based on local residual energy was proposed.In the scheme,the sink periodically moves to a new location with the highest stay-value defined by the average residual energy and the number of neighbors.The scheme can balance energy consumption and prevent nodes around sink from draining their energy very quickly in the networks.The simulation results show that the scheme can prolong the network lifetime by 26%-65%compared with the earlier schemes where the sink is static or moves randomly.展开更多
In this paper, we conduct research on the pragmatics of politeness principle of bulletin board system based on the differences of gender and habits. The openness of the Internet makes all kinds of information received...In this paper, we conduct research on the pragmatics of politeness principle of bulletin board system based on the differences of gender and habits. The openness of the Internet makes all kinds of information received into the vision of an equal chance and web sites in order to improve the hit rate which causes the traffic of commercial purposes such as tabloidization tend to be more negative news spread. To strengthen the research of network language management strategy, it has very important theoretical significance and practical meaning analyzed. Our proposed methodology will help researchers to understand the approaches to use the pragrnatics of politeness.展开更多
This paper presents two optimizations to improve the network receive performance in Xen, espe- cially for receiving small packets, by reducing per-packet overhead of network virtualization. First, the universal receiv...This paper presents two optimizations to improve the network receive performance in Xen, espe- cially for receiving small packets, by reducing per-packet overhead of network virtualization. First, the universal receive aggregation assembles incoming packets to decrease the cost of software bridge and bridge netfilter, no matter which protocol these packets use or whether they belong to the same TCP link. Second, the grant page sharing makes as many packets as possible share a single grant page to decrease the cost of expensive grant operations effectively. Experiment demonstrates that compared with default network virtualization in Xen, these two optimizations can reduce CPU cycles per packet by 31.20%, and improve UDP and TCP throughput by 37.73% and 25.62% on average.展开更多
The authors report a super low power Medical Implant Communication Service (MICS) band receiver for a high resolution epi-retinal prosthesis (BionicEye). The frequency shift keying (FSK) receiver consumes less t...The authors report a super low power Medical Implant Communication Service (MICS) band receiver for a high resolution epi-retinal prosthesis (BionicEye). The frequency shift keying (FSK) receiver consumes less than 1.5 mW power with 1 V supply. It is able to achieve a maximum data rate of 400 kb/s. This paper presents the research work carried out on designing a fully-integrated sub-threshold receiver fabricated on a 65 nm complimentary metal oxide semiconductor (CMOS) chip. In order to achieve super low power consumption, more than 90% of the transistors in all analog building blocks are operated in sub-threshold region. System level issues, such as required receiver architecture and specifications are also addressed.展开更多
This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fl...This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fluctuation of interference power and the measurement noise due to receiver noise. The well-known Finite Impulse Response (FIR) structure filter is adopted for both the interference and the noise covarianee estimation. The proposed mechanism provides both the filtered interference power and the filtered number of active co-channel interferers, which shows good inherent properties. And the filtered interference power is not affected by the constant number of active co-channel interferes. It is also shown that the filtered number of active co-channel interference is separated from the filtered interference power. From discussions about the choice of design parameters such as window length and eovariance ratio, they can make the estimation performance of the proposed FIR filtering based mechanism as good as possible. Via extensive computer simulations, the performance of the proposed mechanism is shown to be superior to the existing Kalman filtering based mechanism.展开更多
In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited...In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited energy storage capacity. Therefore, surplus energy of a node can be utilized for strengthening packet delivery efficiency and improving data collection rate. In this work, we propose an algorithm to compute an upper data generation rate that maximizes it as an optimization problem for a network with multiple sinks, which is formulated as a linear programming problem. Subsequently, a dual problem by introducing Lagrange multipliers is constructed, and subgradient algorithms are used to solve it in a distributed manner. The resulting algorithms are guaranteed to converge to an optimal data generation rate, which are illustrated by an example in which an optimum data generation rate is computed for a network of randomly distributed nodes. Through extensive simulation and experiments, we demonstrate our algorithm is efficient to maximize data collection rate in rechargeable wireless sensor networks.展开更多
This study aims to identify the current situation and problems of environmental information statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold ...This study aims to identify the current situation and problems of environmental information statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold at online stores in Japan, and then to suggest how to improve the situation, through a questionnaire survey conducted among businesses that operate online stores and online malls with multiple online stores. The findings of this study are summarized into the following two points: (l) It is found out that environmental information statement for the home appliances at online stores has four problems: (i) less information on "three Rs (reduce, reuse and recycle)" and "chemical substances" than the one on "energy conservation"; (ii) cost for providing environmental information statement; (iii) issues associated with a label and mark placement; (iv) issues associated with energy conservation statement. (2) Improvements are suggested for each of the four problems listed above, and shown are (i) the effectiveness of, and need to promote, a label and mark placement; (ii) cost burden on buyers; (iii) need of active efforts made by businesses and of dissemination of legal regulations to businesses.展开更多
WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of...WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.展开更多
A novel access protocol called Multiple-Reception Access Protocol (WRAP) and its modification MRAP/WI are proposed. In this protocol, all colliding users with a common code can be identified by the base station due to...A novel access protocol called Multiple-Reception Access Protocol (WRAP) and its modification MRAP/WI are proposed. In this protocol, all colliding users with a common code can be identified by the base station due to the offset of arrival time. Thus they can retransmit access requests under the base station's control. Furthermore new arrivals with higher priority level can interrupt the lower retransmission in order to reduce its access delay although it, increases the lower priority's delay. Simulation results of MRAP and MRAP/WI are given in order to highlight the superior performance of the proposed approach.展开更多
基金the National Natural Science Foundation of China(No.60606009)~~
文摘A 2.4GHz monolithic CMOS receiver with direct-conversion architecture is presented. This quadrature receiver is designed for 802.11b wireless LAN applications at the maximum data rate of 11Mbps as a low-cost solution. Five key blocks,i, e., a low noise amplifier (LNA), a down-conversion mixer, a variable gain amplifier, a low pass filter, and a DC- offset cancellation circuit,are designed based on system design and low noise high linearity considerations. The necessary auxiliary circuits are also included. Fabricated in SMIC 0.18μm 1p6m RF CMOS process, the receiver's performance is measured as:4. 1 dB noise figure, - 7.5dBm input third order intercept point (IIP3) for LNA & mixer at high gain setting, - 14dBm IIP3 for the whole receiver,53dBc @30MHz offset of adjacent channel power rejection,and less than 5mV out- put DC-offset. The receiver consumes 44mA under a 1.8V power supply with I,Q two paths.
文摘In this paper, the security technology of ad hoc networks is studied.To improve the previous multi-receiver signcryption schemes, an ID-based multi-message and multi-receiver signcryption scheme for rekeying in ad hoc networks is proposed.In this scheme, a sender can simultaneously signcrypt n messeges for n receivers, and a receiver can unsigncrypt the ciphertext to get his message with his own private key.An analysis of this scheme indicates that it achieves authenticity and confidentiality in the random oracle model while being of lower computation and communication overhead.Finally, for the application of our scheme in ad hoc, a threshold key updating protocol for ad hoc networks is given.
文摘With the evolution of network technologies, the deficiencies of TCP protocol are becoming more and more distinct. The new TCP implementation, called Receiver Advertisement Based TCP (TCP-Rab) proposed here to eliminate these deficiencies, adopts two basic mechanisms: (1) Bandwidth Estimation and (2) Immediate Recovery. Bandwidth estimation is carried out at the receiver, and the result is sent back to the sender via the acknowledgments. Immediate Recovery guarantees high performance even in lossy link. Rab can distinguish the reason for packet loss, and thus adopt appropriate recovery strategy. For loss by network congestion, it will back off its congestion window, and for loss by link errors, it will recover the congestion window immediately. Simulations indicated that Rab has superiority over other TCP implementations.
基金Supported by the program for New Century Excellent Talents at the University of China under Grant No.NCET-06-0554the National Natural Science Foundation of China under Grant Nos.60677001,50672001,10874122,and 10747146+2 种基金the Science-Technology Fund of Anhui Province for Outstanding Youth under Grant No.06042087the Key Fund of the Ministry of Education of China under Grant No.206063the Natural Science Foundation of Guangdong Province under Grant Nos.06300345 and 7007806
文摘We present a scheme for remotely preparing a state via the controls of many agents in a network.In thescheme,the agents' controls are achieved by utilizing quantum key distribution.Generally,the original state can berestored by the receiver with probability 1/2 if all the agents collaborate.However,for certain type of original states therestoration probability is unit.
基金Project(60673164)supported by the National Natural Science Foundation of ChinaProject(20060533057)supported by the Specialized Research Foundation for the Doctoral Program of Higher Education of China
文摘In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving scheme for the sink based on local residual energy was proposed.In the scheme,the sink periodically moves to a new location with the highest stay-value defined by the average residual energy and the number of neighbors.The scheme can balance energy consumption and prevent nodes around sink from draining their energy very quickly in the networks.The simulation results show that the scheme can prolong the network lifetime by 26%-65%compared with the earlier schemes where the sink is static or moves randomly.
文摘In this paper, we conduct research on the pragmatics of politeness principle of bulletin board system based on the differences of gender and habits. The openness of the Internet makes all kinds of information received into the vision of an equal chance and web sites in order to improve the hit rate which causes the traffic of commercial purposes such as tabloidization tend to be more negative news spread. To strengthen the research of network language management strategy, it has very important theoretical significance and practical meaning analyzed. Our proposed methodology will help researchers to understand the approaches to use the pragrnatics of politeness.
文摘This paper presents two optimizations to improve the network receive performance in Xen, espe- cially for receiving small packets, by reducing per-packet overhead of network virtualization. First, the universal receive aggregation assembles incoming packets to decrease the cost of software bridge and bridge netfilter, no matter which protocol these packets use or whether they belong to the same TCP link. Second, the grant page sharing makes as many packets as possible share a single grant page to decrease the cost of expensive grant operations effectively. Experiment demonstrates that compared with default network virtualization in Xen, these two optimizations can reduce CPU cycles per packet by 31.20%, and improve UDP and TCP throughput by 37.73% and 25.62% on average.
文摘The authors report a super low power Medical Implant Communication Service (MICS) band receiver for a high resolution epi-retinal prosthesis (BionicEye). The frequency shift keying (FSK) receiver consumes less than 1.5 mW power with 1 V supply. It is able to achieve a maximum data rate of 400 kb/s. This paper presents the research work carried out on designing a fully-integrated sub-threshold receiver fabricated on a 65 nm complimentary metal oxide semiconductor (CMOS) chip. In order to achieve super low power consumption, more than 90% of the transistors in all analog building blocks are operated in sub-threshold region. System level issues, such as required receiver architecture and specifications are also addressed.
文摘This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fluctuation of interference power and the measurement noise due to receiver noise. The well-known Finite Impulse Response (FIR) structure filter is adopted for both the interference and the noise covarianee estimation. The proposed mechanism provides both the filtered interference power and the filtered number of active co-channel interferers, which shows good inherent properties. And the filtered interference power is not affected by the constant number of active co-channel interferes. It is also shown that the filtered number of active co-channel interference is separated from the filtered interference power. From discussions about the choice of design parameters such as window length and eovariance ratio, they can make the estimation performance of the proposed FIR filtering based mechanism as good as possible. Via extensive computer simulations, the performance of the proposed mechanism is shown to be superior to the existing Kalman filtering based mechanism.
基金supported by The Natural Science Foundation of Jiangsu Province of China(Grant No.BK20141474)funded by China Postdoctoral Science Foundation(Grant No.2015M571639)+3 种基金three Projects Funded by The Jiangsu Planned Projects for Postdoctoral Research Funds(Grant No.1402018C)The Key Laboratory of Computer Network and Information Integration(Southeast University)Ministry of Education(Grant No.K93-9-2015-09C)The Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions
文摘In rechargeable wireless sensor networks, a sensor cannot be always benefi cial to conserve energy when a network can harvest excessive energy from the environment due to its energy replenished continually and limited energy storage capacity. Therefore, surplus energy of a node can be utilized for strengthening packet delivery efficiency and improving data collection rate. In this work, we propose an algorithm to compute an upper data generation rate that maximizes it as an optimization problem for a network with multiple sinks, which is formulated as a linear programming problem. Subsequently, a dual problem by introducing Lagrange multipliers is constructed, and subgradient algorithms are used to solve it in a distributed manner. The resulting algorithms are guaranteed to converge to an optimal data generation rate, which are illustrated by an example in which an optimum data generation rate is computed for a network of randomly distributed nodes. Through extensive simulation and experiments, we demonstrate our algorithm is efficient to maximize data collection rate in rechargeable wireless sensor networks.
文摘This study aims to identify the current situation and problems of environmental information statement for major four home appliances (refrigerators, washing machines, air conditioners and television receivers) sold at online stores in Japan, and then to suggest how to improve the situation, through a questionnaire survey conducted among businesses that operate online stores and online malls with multiple online stores. The findings of this study are summarized into the following two points: (l) It is found out that environmental information statement for the home appliances at online stores has four problems: (i) less information on "three Rs (reduce, reuse and recycle)" and "chemical substances" than the one on "energy conservation"; (ii) cost for providing environmental information statement; (iii) issues associated with a label and mark placement; (iv) issues associated with energy conservation statement. (2) Improvements are suggested for each of the four problems listed above, and shown are (i) the effectiveness of, and need to promote, a label and mark placement; (ii) cost burden on buyers; (iii) need of active efforts made by businesses and of dissemination of legal regulations to businesses.
基金This work was supported in part by China National Natural Science Foundation under Grant 61271185,and the Fundamental Research Funds for the Central Universities
文摘WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System (ColTS). However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.
文摘A novel access protocol called Multiple-Reception Access Protocol (WRAP) and its modification MRAP/WI are proposed. In this protocol, all colliding users with a common code can be identified by the base station due to the offset of arrival time. Thus they can retransmit access requests under the base station's control. Furthermore new arrivals with higher priority level can interrupt the lower retransmission in order to reduce its access delay although it, increases the lower priority's delay. Simulation results of MRAP and MRAP/WI are given in order to highlight the superior performance of the proposed approach.