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Sensor Network with Multiple Mobile Access Points
- in Proc. 2004 CISS
, 2004
"... We consider sensor networks with mobile access points where data at sensor nodes are collected by multiple mobile access points. Using throughput and energy efficiency as performance measures, we address the optimal coverage areas of and the cooperation among the mobile access points. We show that w ..."
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We consider sensor networks with mobile access points where data at sensor nodes are collected by multiple mobile access points. Using throughput and energy efficiency as performance measures, we address the optimal coverage areas of and the cooperation among the mobile access points. We show that when the mobile access points do not cooperate in demodulation, disjoint coverage areas are optimal for throughput while completely overlapped coverage areas are optimal for energy efficiency. When the mobile access points decode their received packets jointly, the optimal configuration appears to have a phase transition. Specifically, in order to maximize throughput, the coverage areas of the mobile access points should be completely overlapped when SNR is smaller than a threshold and disjoint otherwise.
The price of certainty: “waterslide curves” and the gap to capacity
- IEEE Trans. Inform. Theory, Submitted 2007. [Online]. Available: http://arxiv.org/abs/0801.0352
"... The classical problem of reliable point-to-point digital communication is to achieve a low probability of error while keeping the rate high and the total power consumption small. Traditional information-theoretic analysis uses explicit models for the communication channel to study the power spent in ..."
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Cited by 14 (9 self)
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The classical problem of reliable point-to-point digital communication is to achieve a low probability of error while keeping the rate high and the total power consumption small. Traditional information-theoretic analysis uses explicit models for the communication channel to study the power spent in transmission. The resulting bounds are expressed using ‘waterfall ’ curves that convey the revolutionary idea that unboundedly low probabilities of biterror are attainable using only finite transmit power. However, practitioners have long observed that the decoder complexity, and hence the total power consumption, goes up when attempting to use sophisticated codes that operate close to the waterfall curve. This paper gives an explicit model for power consumption at an idealized decoder that allows for extreme parallelism in implementation. The decoder architecture is in the spirit of message passing and iterative decoding for sparse-graph codes, but is further idealized in that it allows for more computational power than is currently known to be implementable. Generalized sphere-packing arguments are used to derive lower bounds on the decoding power needed for any possible code given only the gap from the Shannon limit and the desired probability of error. As the gap goes to zero, the energy per bit spent in decoding is shown to go to infinity. This suggests that to optimize total power, the transmitter should operate at a power that is strictly above the minimum demanded by the Shannon capacity. The lower bound is plotted to show an unavoidable tradeoff between the average bit-error probability and the total power used in transmission and decoding. In the spirit of conventional waterfall curves, we call these ‘waterslide’ curves. The bound is shown to be order optimal by showing the existence of codes that can achieve similarly shaped waterslide curves under the proposed idealized model of decoding. 1 The price of certainty: “waterslide curves ” and the gap to capacity I.
doi:10.1093/comjnl/bxp110 Heuristic Approaches for Transmission Scheduling in Sensor Networks with
, 2009
"... A large part of the energy budget of traditional sensor networks is consumed by the hop-by-hop routing of the collected information to the static sink. In many applications it is possible to replace the static sink with one or more mobile sinks that move in a sensor field and collect the data throug ..."
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Cited by 4 (2 self)
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A large part of the energy budget of traditional sensor networks is consumed by the hop-by-hop routing of the collected information to the static sink. In many applications it is possible to replace the static sink with one or more mobile sinks that move in a sensor field and collect the data through one-hop transmissions.This greatly reduces the power consumption of the nodes, which can be further reduced by choosing the appropriate moment of transmission. In general, the transmission energy increases quickly with the distance, and thus it makes sense for the nodes to transmit when one of the mobile sinks is in close proximity. Seeing the node as an autonomous agent, it needs to choose its actions of transmitting or buffering the collected data based on what it knows about the environment and its predictions about the future. The sensor agent needs to appropriately balance the following two objectives: the maximization of the utility of the collected and transmitted data and the minimization of the energy expenditure. We introduce the cummulative policy penalty as an expression of this interdependent pair of requirements. As a baseline, we describe a graph-theory-based approach for calculating the optimal policy in a complete knowledge setting. Then, we describe and compare three heuristics based on different principles (imitation of human decision making, stochastic transmission and constant risk). We compare the proposed approaches in an experimental study under a variety of scenarios.
Sensitivity and Coding of Opportunistic ALOHA in Sensor Networks with Mobile Access
- JOURNAL OF VLSI SIGNAL PROCESSING
, 2005
"... We consider a distributed medium access protocol, Opportunistic ALOHA, for reachback in sensor networks with mobile access points (AP). We briefly discuss some properties of the protocol, like throughput and transmission control for an orthogonal CDMA physical layer. We then consider the incorporati ..."
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Cited by 2 (2 self)
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We consider a distributed medium access protocol, Opportunistic ALOHA, for reachback in sensor networks with mobile access points (AP). We briefly discuss some properties of the protocol, like throughput and transmission control for an orthogonal CDMA physical layer. We then consider the incorporation of necessary side information like location into the transmission control and numerically demonstrate the loss in throughput in the absence of such information. Through simulations, we discuss the robustness and sensitivity of the protocol under various modeling errors and propose strategies to allow for errors in estimation of some parameters without reduction in the throughput. For networks, where the sensors are allowed to collaborate, we consider three coding schemes for reliable transmission: spreading code independent, spreading code dependent transmission and coding across sensors. These schemes are compared in terms of achievable rates and random coding error exponents. The coding across sensors scheme has comparable achievable rates to the spreading code dependent scheme, but requires the additional transmission of sensor ID. However, the scheme does not require the mobile AP to send data through the beacon unlike the other two schemes. The use of these coding schemes to overcome sensitivity is demonstrated through simulations.
EURASIP Journal on Wireless Communications and Networking 2005:5, 610–624 c ○ 2005 B. Zhao and M. C. Valenti Position-Based Relaying with Hybrid-ARQ for Efficient Ad Hoc Networking
, 2005
"... This paper presents and analyzes an integrated, cross-layer protocol for wireless ad hoc networking that utilizes position location (e.g., through an onboard GPS receiver) and jointly performs the operations of network-layer relaying and link-layer ARQbased error control. The protocol is a modified ..."
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This paper presents and analyzes an integrated, cross-layer protocol for wireless ad hoc networking that utilizes position location (e.g., through an onboard GPS receiver) and jointly performs the operations of network-layer relaying and link-layer ARQbased error control. The protocol is a modified version of the hybrid-ARQ-based intra-cluster geographically-informed relaying (HARBINGER) protocol (2005) and unifies the concepts of geographic random forwarding (GeRaF) (2003), point-to-point hybrid-ARQ (2001), and cooperative diversity (2004). The modification makes the protocol especially suitable for sensor networks whose nodes cycle in and out of sleep states and permits a closed-form analysis. Performance bounds and simulations indicate the potential for a dramatic improvement in the tradeoff between active node density and end-to-end message delay as compared with the GeRaF protocol and are used to motivate further study of practical implementation issues. Keywords and phrases: relay networks, ad hoc networking, cross-layer protocols, hybrid-ARQ, GeRaF, HARBINGER. 1.
DETECTION OF BLACKHOLE ATTACK IN DISTRIBUTED WIRELESS SENSOR NETWORKS
"... Abstract:Wireless senor network is one of the emerging technologies where it provides various kinds of applications for military and societal purpose.The sensing methodology which is a combination of wireless communication and processing power makes it as one of the powerful technology. Incorporatin ..."
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Abstract:Wireless senor network is one of the emerging technologies where it provides various kinds of applications for military and societal purpose.The sensing methodology which is a combination of wireless communication and processing power makes it as one of the powerful technology. Incorporating security into wireless sensor network is one of difficult task due to their limitations. Wireless sensors networks are prone to various kinds of threats.One of the security attacks to wireless sensor network is a black hole attack. In black hole attack, the malicious node will advertise itself stating that it has the shortest route to the destination by exploiting routing protocol. The black hole attack is a kind of denial of service attack. This paper deals with the architecture of sensor network with access point, vulnerabilitiesof adhoc on distance vector routing protocol associated with black hole attack and detection mechanism. To detect black hole attack in the network, authentication mechanism and sensor network with mobile access point using Adhoc On Distance Vector Routing protocol is used.To detect the number of black hole nodes present in the network, fusion rule is used. The fusion rule used in this paper is q-out-of-m rule, which provides good tradeoff between false alarm rate and miss detection rate.
A. Information Retrieval in Sensor Networks
"... Abstract — We consider information retrieval in a wireless sensor network deployed for the reconstruction of a spatially correlated signal field. Referred to as QUality-of-service specific Information REtrieval (QUIRE), the proposed protocol optimizes the network performance under the metric of info ..."
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Abstract — We consider information retrieval in a wireless sensor network deployed for the reconstruction of a spatially correlated signal field. Referred to as QUality-of-service specific Information REtrieval (QUIRE), the proposed protocol optimizes the network performance under the metric of information rate per Joule while ensuring a given QoS. Based on the density of sensor deployment and the QoS specified by the maximum distortion for reconstructing the signal field, QUIRE partitions the sensor network into disjoint and equal-sized cells. The cell size is chosen to minimize the number of transmissions required for a given QoS by exploiting the spatial correlation of the signal field. Adopting the cross-layer design methodology that integrates opportunistic carrier sensing and optimal cell activation, QUIRE eliminates redundant transmissions and fully utilizes the channel reception capability in a fading environment.
TO APPEAR IN THE IEEE TRANSACTIONS ON MOBILE COMPUTING. 1 Adaptive Cluster-Based Data Collection in Sensor Networks with Direct Sink Access
"... Abstract—Recently wireless sensor networks featuring direct sink access have been studied as an efficient architecture to gather and process data for numerous applications. In this paper, we focus on the joint effect of clustering and data correlation on the performance of such networks. More specif ..."
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Abstract—Recently wireless sensor networks featuring direct sink access have been studied as an efficient architecture to gather and process data for numerous applications. In this paper, we focus on the joint effect of clustering and data correlation on the performance of such networks. More specifically, we propose a novel Cluster-based Data Collection scheme for sensor networks with Direct Sink Access (CDC-DSA), and provide an analytical framework to evaluate its performance in terms of energy consumption, latency, and robustness. In our scheme, CHs use a low-overhead and simple medium access control (MAC) conceptually similar to ALOHA to contend for the reachback channel to the data sink. Since in our model data is collected periodically, the packet arrival is not modeled by a continuous random process and, therefore, we base our framework on a transient analysis rather than a steady state analysis. Using random geometry tools, we study how the optimal average cluster size and energy savings, under the proposed MAC, vary according to the level of data correlation in the network. Extensive simulations for various protocol parameters show that our analysis is fairly accurate for a wide range of parameters. Our results suggest that despite the tradeoff between energy consumption and latency, both of which can be substantially reduced by a proper clustering design. Index Terms—Wireless sensor networks, adaptive clustering, data collection latency, energy efficient communication, data correlation. I.
Energy Efficiency of Large-Scale Wireless Networks: Proactive Versus Reactive Networking
"... Abstract—An analytical approach to the characterization of energy consumption of large-scale wireless networks is presented. The radio model includes energy consumption of nodes at various operating states. We analyze the total energy consumption of the proactive and the reactive networking strategi ..."
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Abstract—An analytical approach to the characterization of energy consumption of large-scale wireless networks is presented. The radio model includes energy consumption of nodes at various operating states. We analyze the total energy consumption of the proactive and the reactive networking strategies, taking into account transmitting, listening, and sleeping energy. Scaling laws with respect to the increase of node density and geographical size are derived. Energy efficiency and overhead at the physical and the network layers are evaluated against message duty cycle, channel fading rate, and node mobility. The crossover point in message duty cycle below which reactive network has assured advantages is obtained. The analysis is then applied to large-scale sensor networks for applications involving data-centric and location-centric queries. The ad hoc sensor network architecture is compared with sensor networks with mobile access points. Index Terms—Energy consumption analysis, energy scaling law, mobile ad hoc networks, proactive and reactive networking, sensor networks. I.
