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365
Energy harvesting sensor nodes: Survey and implications
- Department of Computer Science and Engineering
, 2008
"... Sensor networks with battery-powered nodes can seldom simultaneously meet the design goals of lifetime, cost, sensing reliability and sensing and transmission coverage. Energy-harvesting, converting ambient energy to electrical energy, has emerged as an alternative to power sensor nodes. By exploiti ..."
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Cited by 125 (0 self)
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Sensor networks with battery-powered nodes can seldom simultaneously meet the design goals of lifetime, cost, sensing reliability and sensing and transmission coverage. Energy-harvesting, converting ambient energy to electrical energy, has emerged as an alternative to power sensor nodes. By exploiting recharge opportunities and tuning performance parameters based on current and expected energy levels, energy harvesting sensor nodes have the potential to address the conflicting design goals of lifetime and performance. This paper surveys various aspects of energy harvesting sensor systems — architecture, energy sources and storage technologies and examples of harvesting-based nodes and applications. The study also discusses the implications of recharge opportunities on sensor node operation and design of sensor network solutions. 1
RI-MAC: a receiver-initiated asynchronous duty cycle MAC protocol for dynamic traffic loads in wireless sensor networks
- in Proc. ACM SenSys
, 2008
"... The problem of idle listening is one of the most significant sources of energy consumption in wireless sensor nodes, and many techniques have been proposed based on duty cycling to reduce this cost. In this paper, we present a new asynchronous duty cycle MAC protocol, called Receiver-Initiated MAC ( ..."
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Cited by 103 (0 self)
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The problem of idle listening is one of the most significant sources of energy consumption in wireless sensor nodes, and many techniques have been proposed based on duty cycling to reduce this cost. In this paper, we present a new asynchronous duty cycle MAC protocol, called Receiver-Initiated MAC (RI-MAC), that uses receiver-initiated data transmission in order to efficiently and effectively operate over a wide range of traffic loads. RI-MAC attempts to minimize the time a sender and its intended receiver occupy the wireless medium to find a rendezvous time for exchanging data, while still decoupling the sender and receiver’s duty cycle schedules. We show the performance of RI-MAC through detailed ns-2 simulation and through measurements of an implementation in TinyOS in a testbed of MICAz motes. Compared to the prior asynchronous duty cycling approach of X-MAC, RI-MAC achieves higher throughput, packet delivery ratio, and power efficiency under a wide range of traffic loads. Especially when there are contending flows, such as bursty traffic or transmissions from hidden nodes, RI-MAC significantly improves throughput and packet delivery ratio. Even under light traffic load for which X-MAC is optimized, RI-MAC achieves the same high performance in terms of packet delivery ratio and latency while maintaining comparable power efficiency.
IP is Dead, Long Live IP for Wireless Sensor Networks
- THE 6TH INTERNATIONAL CONFERENCE ON EMBEDDED NETWORKED SENSOR SYSTEMS (SENSYS'08)
, 2008
"... A decade ago as wireless sensor network research took off many researchers in the field denounced the use of IP as inadequate and in contradiction to the needs of wireless sensor networking. Since then the field has matured, standard links have emerged, and IP has evolved. In this paper, we present ..."
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Cited by 98 (5 self)
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A decade ago as wireless sensor network research took off many researchers in the field denounced the use of IP as inadequate and in contradiction to the needs of wireless sensor networking. Since then the field has matured, standard links have emerged, and IP has evolved. In this paper, we present the design of a complete IPv6-based network architecture for wireless sensor networks. We validate the architecture with a production-quality implementation that incorporates many techniques pioneered in the sensor network community, including duty-cycled link protocols, header compression, hop-by-hop forwarding, and efficient routing with effective link estimation. In addition to providing interoperability with existing IP devices, this implementation was able to achieve an average duty-cycle of 0.65%, average per-hop latency of 62ms, and a data reception rate of 99.98 % over a period of 4 weeks in a real-world home-monitoring application where each node generates one application packet per minute. Our results outperform existing systems that do not adhere to any particular standard or architecture. In light of this demonstration of full IPv6 capability, we review the central arguments that led the field away from IP. We believe that the presence of an architecture, specifically an IPv6-based one, provides a strong foundation for wireless sensor networks going forward.
Software-based on-line energy estimation for sensor nodes
- in Fourth Workshop on Embedded Networked Sensors
, 2007
"... Energy is of primary importance in wireless sensor networks. By being able to estimate the energy consumption of the sensor nodes, applications and routing protocols are able to make informed decisions that increase the lifetime of the sensor network. However, it is in general not possible to measur ..."
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Cited by 81 (20 self)
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Energy is of primary importance in wireless sensor networks. By being able to estimate the energy consumption of the sensor nodes, applications and routing protocols are able to make informed decisions that increase the lifetime of the sensor network. However, it is in general not possible to measure the energy consumption on popular sensor node platforms. In this paper, we present and evaluate a softwarebased on-line energy estimation mechanism that estimates the energy consumption of a sensor node. We evaluate the mechanism by comparing the estimated energy consumption with the lifetime of capacitor-powered sensor nodes. By implementing and evaluating the X-MAC protocol, we show how software-based on-line energy estimation can be used to empirically evaluate the energy efficiency of sensor network protocols. 1.
Practical Asynchronous Neighbor Discovery and Rendezvous for Mobile Sensing Applications
- In SenSys’08
, 2008
"... We present Disco, an asynchronous neighbor discovery and rendezvous protocol that allows two or more nodes to operate their radios at low duty cycles (e.g. 1%) and yet still discover and communicate with one another during infrequent, opportunistic encounters without requiring any prior synchronizat ..."
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Cited by 77 (6 self)
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We present Disco, an asynchronous neighbor discovery and rendezvous protocol that allows two or more nodes to operate their radios at low duty cycles (e.g. 1%) and yet still discover and communicate with one another during infrequent, opportunistic encounters without requiring any prior synchronization information. The key challenge is to operate the radio at a low duty cycle but still ensure that discovery is fast, reliable, and predictable over a range of operating conditions. Disco nodes pick a pair of prime numbers such that the sum of their reciprocals is equal to the desired radio duty cycle. Each node increments a local counter with a globally-fixed period. If a node’s local counter value is divisible by either of its primes, then the node turns on its radio for one period. This protocol ensures that two nodes will have some overlapping radio on-time within a bounded number of periods, even if nodes independently set their own duty cycle. Once a neighbor is discovered, and its wakeup schedule known, rendezvous is just a matter of being awake during the neighbor’s next wakeup period, for synchronous rendezvous, or during an overlapping wake period, for asynchronous rendezvous.
Design and evaluation of a versatile and efficient receiver-initiated link layer for low-power wireless,” in ACM SenSys,
, 2010
"... Abstract We present A-MAC, a receiver-initiated link layer for low-power wireless networks that supports several services under a unified architecture, and does so more efficiently and scalably than prior approaches. A-MAC's versatility stems from layering unicast, broadcast, wakeup, pollcast, ..."
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Cited by 67 (5 self)
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Abstract We present A-MAC, a receiver-initiated link layer for low-power wireless networks that supports several services under a unified architecture, and does so more efficiently and scalably than prior approaches. A-MAC's versatility stems from layering unicast, broadcast, wakeup, pollcast, and discovery above a single, flexible synchronization primitive. A-MAC's efficiency stems from optimizing this primitive and with it the most consequential decision that a low-power link makes: whether to stay awake or go to sleep after probing the channel. Today's receiver-initiated protocols require more time and energy to make this decision, and they exhibit worse judgment as well, leading to many false positives and negatives, and lower packet delivery ratios. A-MAC begins to make this decision quickly, and decides more conclusively and correctly in both the negative and affirmative. A-MAC's scalability comes from reserving one channel for the initial handshake and different channels for data transfer. Our results show that: (i) a unified implementation is possible; (ii) A-MAC's idle listening power increases by just 1.12× under interference, compared to 17.3× for LPL and 54.7× for RI-MAC; (iii) A-MAC offers high single-hop delivery ratios, even with multiple contending senders; (iv) network wakeup is faster and far more channel efficient than LPL; and (v) collection routing performance exceeds the state-of-the-art.
An adaptive communication architecture for wireless sensor networks
- in Proceedings of the Fifth ACM Conference on Networked Embedded Sensor Systems (SenSys 2007
, 2007
"... As sensor networks move towards increasing heterogeneity, the number of link layers, MAC protocols, and underlying transportation mechanisms increases. System developers must adapt their applications and systems to accommodate a wide range of underlying protocols and mechanisms. However, existing co ..."
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Cited by 66 (15 self)
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As sensor networks move towards increasing heterogeneity, the number of link layers, MAC protocols, and underlying transportation mechanisms increases. System developers must adapt their applications and systems to accommodate a wide range of underlying protocols and mechanisms. However, existing communication architectures for sensor networks are not designed for this heterogeneity and therefore the system developer must redevelop their systems for each underlying communication protocol or mechanism. To remedy this situation, we present a communication architecture that adapts to a wide range of underlying communication mechanisms, from the MAC layer to the transport layer, without requiring any changes to applications or protocols. We show that the architecture is expressive enough to accommodate typical sensor network protocols. Measurements show that the increase in execution time over a non-adaptive architecture is small. Dis-
MAC Essentials for Wireless Sensor Networks
, 2009
"... The wireless medium being inherently broadcast in nature and hence prone to interferences requires highly optimized medium access control (MAC) protocols. This holds particularly true for wireless sensor networks (WSNs) consisting of a large amount of miniaturized battery-powered wireless networked ..."
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Cited by 61 (1 self)
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The wireless medium being inherently broadcast in nature and hence prone to interferences requires highly optimized medium access control (MAC) protocols. This holds particularly true for wireless sensor networks (WSNs) consisting of a large amount of miniaturized battery-powered wireless networked sensors required to operate for years with no human intervention. There has hence been a growing interest on understanding and optimizing WSN MAC protocols in recent years, where the limited and constrained resources have driven research towards primarily reducing energy consumption of MAC functionalities. In this paper, we provide a comprehensive state-of-the-art study in which we thoroughly expose the prime focus of WSN MAC protocols, design guidelines that inspired these protocols, as well as drawbacks and shortcomings of the existing solutions and how existing and emerging technology will influence future
BoX-MACs: Exploiting Physical and Link Layer Boundaries in LowPower Networking
, 2008
"... We present two MAC layers for ultra-low-power wireless networking, BoX-MAC-1 and BoX-MAC-2. Leading lowpower MACs today reside in a single layer: BMAC exploits only the physical-layer while XMAC utilizes only the link-layer. In contrast, BoX-MAC-1 and BoX-MAC-2 are cross-layer protocols. BoX-MAC-1 i ..."
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Cited by 60 (2 self)
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We present two MAC layers for ultra-low-power wireless networking, BoX-MAC-1 and BoX-MAC-2. Leading lowpower MACs today reside in a single layer: BMAC exploits only the physical-layer while XMAC utilizes only the link-layer. In contrast, BoX-MAC-1 and BoX-MAC-2 are cross-layer protocols. BoX-MAC-1 incorporates link-layer information into a predominantly physical-layer sampling approach. BoX-MAC-2 combines physical-layer information into a predominantly link-layer packetized approach. Through analysis and experiments on CC2420-based platforms, we find these cross-layer protocols consume up to 40-50 % less energy than XMAC and 30 % less energy than BMAC under reasonable workloads. Furthermore, BoX-MAC-2 yields up to 46 % more throughput than its XMAC counterpart. Together, BoX-MAC protocols provide a comprehensive set of low-power link-layer primitives for a wide range of network workloads. The advantages of these crosslayer MAC designs over single-layer approaches provide insight on requirements for future radio chip and platform designs. 1.
Efficient Application Integration in IP-Based Sensor Networks
"... Sensor networks are seen as an important part in emerging office and building energy management system, but the integration of sensor networks with future energy management systems is still an open problem. We present an IP-based sensor network system where nodes communicate their information using ..."
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Cited by 58 (3 self)
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Sensor networks are seen as an important part in emerging office and building energy management system, but the integration of sensor networks with future energy management systems is still an open problem. We present an IP-based sensor network system where nodes communicate their information using Web services, allowing direct integration in modern IT systems. Our system uses two mechanisms to provide a good performance and low-power operation: a session-aware power-saving radio protocol and the use of the HTTP Conditional GET mechanism. We perform an extensive evaluation of our system and show that Web services are a viable mechanism for use in low-power sensor networks. Our results show that Web service requests can be completed well below one second and with a low power consumption, even in a multi-hop setting.
