Asis Nasipuri | University of North Carolina at Charlotte (original) (raw)

Papers by Asis Nasipuri

ACM Transactions on Embedded Computing Systems

Batteryless wireless sensor networks that rely on energy harvested from the environment often exh... more Batteryless wireless sensor networks that rely on energy harvested from the environment often exhibit random power outages due to limitations of energy resources, which give rise to intermittent co...

Publisher Summary Communication is maintained by the transmission of data packets over a common w... more Publisher Summary Communication is maintained by the transmission of data packets over a common wireless channel. The absence of any fixed infrastructure such as an array of base stations, make ad hoc networks radically different from other wireless local area networks (LANs). All nodes in an ad hoc network are required to relay packets on behalf of other nodes. Hence, a mobile ad hoc network is sometimes called a multihop wireless network. The physical layer must tackle the path loss, fading, and multi-user interference to maintain stable communication links between peers. This chapter highlights the main aspects of designing the physical transmission system, which are dependent on the characteristics of the radio propagation channel such as path loss, interference (co-channel), and fading. Directional transmission can reduce the amount of interference, reduce packet error, and directional antennas have a higher gain due to their directivity. Despite these advantages, the usage of ...

Journal of Sensor and Actuator Networks

In this paper, we investigate mechanisms for improving the quality of communications in wireless-... more In this paper, we investigate mechanisms for improving the quality of communications in wireless-optical broadband access networks (WOBAN), which present a promising solution to meet the growing needs for capacity of access networks. This is achieved by using multiple gateways and multi-channel operation along with a routing protocol that effectively reduces the effect of radio interference. We present a joint route and channel assignment scheme with the objective of maximizing the end-to-end probability of success and minimizing the end-to-end delay for all active upstream traffic in the WOBAN. Performance evaluations of the proposed scheme are presented using ns-2 simulations, which show that the proposed scheme improves the network throughput up to three times and reduces the traffic delay by six times in presence of 12 channels and four network interface cards (NICs), compared to a single channel scenario.

IEEE Access

Wireless sensor networks (WSN) that are powered by energy harvested from the environment, also kn... more Wireless sensor networks (WSN) that are powered by energy harvested from the environment, also known as rechargeable WSNs, typically experience wide variations of energy availability across the network. Such variations can cause frequent node outages at specific locations where energy availability is low, whereas the remaining nodes may receive sufficient energy for continuous operation. The energy availability also varies over time due to environmental factors, which exacerbates the problem. To minimize the impact of such spatial and temporal variations of energy resources, we propose a joint Power COntrol and Routing scheme (PCOR) that adapts the energy consumption in the sensor nodes according to its available energy resources in order to facilitate uninterrupted operations. The scheme is applied to data collecting WSNs with a MAC that utilizes asynchronous duty-cycling for energy conservation. PCOR achieves its objective by reducing the energy consumption at energy-critical sensor nodes, i.e. nodes that have comparatively lower energy resources, using network-wide cooperative power control and route adaptations. This is accomplished by reducing the overhearing at energy-critical nodes, which is a key cause of energy consumption in such networks. We demonstrate through simulations and experimental results that PCOR reduces overhearing at energy-constrained nodes by up to 75% without significantly affecting the end-to-end packet delivery rates. INDEX TERMS Wireless sensor networks, rechargeable networks, power control, adaptive routing, distributed algorithms.

Journal of Sensor and Actuator Networks

We propose a joint channel selection and quality aware routing scheme for multi-channel wireless ... more We propose a joint channel selection and quality aware routing scheme for multi-channel wireless sensor networks that apply asynchronous duty cycling to conserve energy, which is common in many environmental monitoring applications. Energy resources may vary from node to node due to differential consumption as well as availability, as observed in rechargeable sensor networks. A data collection traffic pattern is assumed, where all sensor nodes periodically forward sensor data to a centralized base station (sink). Under these assumptions, the effect of overhearing dominates the energy consumption of the nodes. The proposed scheme achieves lifetime improvement by reducing the energy consumed in overhearing and also by dynamically balancing the lifetimes of nodes. Performance evaluations are presented from experimental tests as well as from extensive simulation studies, which show that the proposed scheme reduces overhearing by ∼60% with just 2 channels without significantly affecting the network performance.

2010 Ieee Global Telecommunications Conference Globecom 2010, 2010

We consider anycast routing to improve the quality of communications in multi-gateway wireless me... more We consider anycast routing to improve the quality of communications in multi-gateway wireless mesh networks. A centralized gateway and route selection scheme is proposed that tries to maximize the end-to-end probability of success and minimize the end-to-end delay of all active traffic flows in the network. The proposed scheme employs a novel route quality metric that is based on the effects of interference on data packet transmissions. We present performance evaluations of the proposed scheme using ns-2 simulations.

Proceedings of the Thirteenth Acm International Symposium on Mobile Ad Hoc Networking and Computing, Jun 11, 2012

We consider the channel assignment problem in multi-channel wireless sensor networks for maximizi... more We consider the channel assignment problem in multi-channel wireless sensor networks for maximizing the network lifetime. We assume a data collection traffic pattern where all nodes forward data periodically to a sink and propose a distributed channel selection scheme that tries to maximize the lifetime of the nodes by controlling the energy consumption from overhearing. Some initial experimental results are

This paper addresses multi-sensor collaboration for the detection of weak and noisy signals using... more This paper addresses multi-sensor collaboration for the detection of weak and noisy signals using wireless sensor networks. The proposed scheme is targeted for the detection of spatially correlated signals, which is common in many sensor network applications. It applies a clustering measure for improving the detection performance with multi-sensor fusion that is traditionally performed by using a counting rule. Associated communication protocols for performing collaboration among sensor nodes for maintaining low communication overhead are presented. Performance of the proposed schemes are obtained using computer simulations.

2015 IEEE International Conference on Communication Workshop (ICCW), 2015

2007 16th International Conference on Computer Communications and Networks, 2007

... Hadi Alasti, William A. Armstrong, Jr., and Asis Nasipuri Department of Electrical and Comput... more ... Hadi Alasti, William A. Armstrong, Jr., and Asis Nasipuri Department of Electrical and Computer Engineering The University of North Carolina ... quantizer as depicted in Figure 3. The quantizer produces output values that are integers in the range ) , ( MAX MAX − centered around ...

2014 IEEE Wireless Communications and Networking Conference (WCNC), 2014

ABSTRACT In this paper, we present the performance of an RSSI based localization scheme for wirel... more ABSTRACT In this paper, we present the performance of an RSSI based localization scheme for wireless sensor networks(WSN) that is proposed to reduce the adverse effects of shadowing caused by obstacles in the field of deployment. The proposed scheme applies spatial correlations between a set of candidate solutions that are obtained from subsets of beacon signals that are used for localization. We analyze the error performance of the proposed scheme using numerical calculations as well experimental results.

Handbook of RF and Wireless Technologies, 2004

Page 1. MOBILE AD HOC NETWORK TAN YUAN SIN (B.Eng (Hons.) NUS) A THESIS SUBMITTED FOR THE DEGREE ... more Page 1. MOBILE AD HOC NETWORK TAN YUAN SIN (B.Eng (Hons.) NUS) A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ENGINEERING DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING NATIONAL UNIVERSITY OF SIGNAPORE 2003 ...

rimtengg.com

Mobile Ad-Hoc Networks (MANETs) are collections of mobile nodes, dynamically forming a temporary ... more Mobile Ad-Hoc Networks (MANETs) are collections of mobile nodes, dynamically forming a temporary network without preexisting network infrastructure or centralized administration. Wireless technologies such as general packet radio service, Wi-Fi, Home ...

… Networks (LCN), 2010

This paper describes the design and deployment of a large scale wireless sensor network (WSN) for... more This paper describes the design and deployment of a large scale wireless sensor network (WSN) for monitoring the health of power equipment in a substation. The sensor network consists of 122 low power nodes that that are spread over an area approximately 1000 × 400 feet in size and perform monitoring of equipment such as transformers, circuit breakers, and compressors. All nodes communicate over a multihop wireless mesh network that uses a dynamic link-quality based routing protocol. A primary objective of this project is to develop effective monitoring applications for the substation using low-cost wireless sensor nodes that can sustain long periods of battery life. We study the battery consumption in the network and present a transmission scheme that conserves communication cost by enabling the sensor nodes to transmit observation samples only when their values are significantly different from those transmitted previously. Experimental results that demonstrate the performance of the sensor network for several monitoring applications are presented.

ACM Transactions on Embedded Computing Systems

Batteryless wireless sensor networks that rely on energy harvested from the environment often exh... more Batteryless wireless sensor networks that rely on energy harvested from the environment often exhibit random power outages due to limitations of energy resources, which give rise to intermittent co...

Publisher Summary Communication is maintained by the transmission of data packets over a common w... more Publisher Summary Communication is maintained by the transmission of data packets over a common wireless channel. The absence of any fixed infrastructure such as an array of base stations, make ad hoc networks radically different from other wireless local area networks (LANs). All nodes in an ad hoc network are required to relay packets on behalf of other nodes. Hence, a mobile ad hoc network is sometimes called a multihop wireless network. The physical layer must tackle the path loss, fading, and multi-user interference to maintain stable communication links between peers. This chapter highlights the main aspects of designing the physical transmission system, which are dependent on the characteristics of the radio propagation channel such as path loss, interference (co-channel), and fading. Directional transmission can reduce the amount of interference, reduce packet error, and directional antennas have a higher gain due to their directivity. Despite these advantages, the usage of ...

Journal of Sensor and Actuator Networks

In this paper, we investigate mechanisms for improving the quality of communications in wireless-... more In this paper, we investigate mechanisms for improving the quality of communications in wireless-optical broadband access networks (WOBAN), which present a promising solution to meet the growing needs for capacity of access networks. This is achieved by using multiple gateways and multi-channel operation along with a routing protocol that effectively reduces the effect of radio interference. We present a joint route and channel assignment scheme with the objective of maximizing the end-to-end probability of success and minimizing the end-to-end delay for all active upstream traffic in the WOBAN. Performance evaluations of the proposed scheme are presented using ns-2 simulations, which show that the proposed scheme improves the network throughput up to three times and reduces the traffic delay by six times in presence of 12 channels and four network interface cards (NICs), compared to a single channel scenario.

IEEE Access

Wireless sensor networks (WSN) that are powered by energy harvested from the environment, also kn... more Wireless sensor networks (WSN) that are powered by energy harvested from the environment, also known as rechargeable WSNs, typically experience wide variations of energy availability across the network. Such variations can cause frequent node outages at specific locations where energy availability is low, whereas the remaining nodes may receive sufficient energy for continuous operation. The energy availability also varies over time due to environmental factors, which exacerbates the problem. To minimize the impact of such spatial and temporal variations of energy resources, we propose a joint Power COntrol and Routing scheme (PCOR) that adapts the energy consumption in the sensor nodes according to its available energy resources in order to facilitate uninterrupted operations. The scheme is applied to data collecting WSNs with a MAC that utilizes asynchronous duty-cycling for energy conservation. PCOR achieves its objective by reducing the energy consumption at energy-critical sensor nodes, i.e. nodes that have comparatively lower energy resources, using network-wide cooperative power control and route adaptations. This is accomplished by reducing the overhearing at energy-critical nodes, which is a key cause of energy consumption in such networks. We demonstrate through simulations and experimental results that PCOR reduces overhearing at energy-constrained nodes by up to 75% without significantly affecting the end-to-end packet delivery rates. INDEX TERMS Wireless sensor networks, rechargeable networks, power control, adaptive routing, distributed algorithms.

Journal of Sensor and Actuator Networks

We propose a joint channel selection and quality aware routing scheme for multi-channel wireless ... more We propose a joint channel selection and quality aware routing scheme for multi-channel wireless sensor networks that apply asynchronous duty cycling to conserve energy, which is common in many environmental monitoring applications. Energy resources may vary from node to node due to differential consumption as well as availability, as observed in rechargeable sensor networks. A data collection traffic pattern is assumed, where all sensor nodes periodically forward sensor data to a centralized base station (sink). Under these assumptions, the effect of overhearing dominates the energy consumption of the nodes. The proposed scheme achieves lifetime improvement by reducing the energy consumed in overhearing and also by dynamically balancing the lifetimes of nodes. Performance evaluations are presented from experimental tests as well as from extensive simulation studies, which show that the proposed scheme reduces overhearing by ∼60% with just 2 channels without significantly affecting the network performance.

2010 Ieee Global Telecommunications Conference Globecom 2010, 2010

We consider anycast routing to improve the quality of communications in multi-gateway wireless me... more We consider anycast routing to improve the quality of communications in multi-gateway wireless mesh networks. A centralized gateway and route selection scheme is proposed that tries to maximize the end-to-end probability of success and minimize the end-to-end delay of all active traffic flows in the network. The proposed scheme employs a novel route quality metric that is based on the effects of interference on data packet transmissions. We present performance evaluations of the proposed scheme using ns-2 simulations.

Proceedings of the Thirteenth Acm International Symposium on Mobile Ad Hoc Networking and Computing, Jun 11, 2012

We consider the channel assignment problem in multi-channel wireless sensor networks for maximizi... more We consider the channel assignment problem in multi-channel wireless sensor networks for maximizing the network lifetime. We assume a data collection traffic pattern where all nodes forward data periodically to a sink and propose a distributed channel selection scheme that tries to maximize the lifetime of the nodes by controlling the energy consumption from overhearing. Some initial experimental results are

This paper addresses multi-sensor collaboration for the detection of weak and noisy signals using... more This paper addresses multi-sensor collaboration for the detection of weak and noisy signals using wireless sensor networks. The proposed scheme is targeted for the detection of spatially correlated signals, which is common in many sensor network applications. It applies a clustering measure for improving the detection performance with multi-sensor fusion that is traditionally performed by using a counting rule. Associated communication protocols for performing collaboration among sensor nodes for maintaining low communication overhead are presented. Performance of the proposed schemes are obtained using computer simulations.

2015 IEEE International Conference on Communication Workshop (ICCW), 2015

2007 16th International Conference on Computer Communications and Networks, 2007

... Hadi Alasti, William A. Armstrong, Jr., and Asis Nasipuri Department of Electrical and Comput... more ... Hadi Alasti, William A. Armstrong, Jr., and Asis Nasipuri Department of Electrical and Computer Engineering The University of North Carolina ... quantizer as depicted in Figure 3. The quantizer produces output values that are integers in the range ) , ( MAX MAX − centered around ...

2014 IEEE Wireless Communications and Networking Conference (WCNC), 2014

ABSTRACT In this paper, we present the performance of an RSSI based localization scheme for wirel... more ABSTRACT In this paper, we present the performance of an RSSI based localization scheme for wireless sensor networks(WSN) that is proposed to reduce the adverse effects of shadowing caused by obstacles in the field of deployment. The proposed scheme applies spatial correlations between a set of candidate solutions that are obtained from subsets of beacon signals that are used for localization. We analyze the error performance of the proposed scheme using numerical calculations as well experimental results.

Handbook of RF and Wireless Technologies, 2004

Page 1. MOBILE AD HOC NETWORK TAN YUAN SIN (B.Eng (Hons.) NUS) A THESIS SUBMITTED FOR THE DEGREE ... more Page 1. MOBILE AD HOC NETWORK TAN YUAN SIN (B.Eng (Hons.) NUS) A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ENGINEERING DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING NATIONAL UNIVERSITY OF SIGNAPORE 2003 ...

rimtengg.com

Mobile Ad-Hoc Networks (MANETs) are collections of mobile nodes, dynamically forming a temporary ... more Mobile Ad-Hoc Networks (MANETs) are collections of mobile nodes, dynamically forming a temporary network without preexisting network infrastructure or centralized administration. Wireless technologies such as general packet radio service, Wi-Fi, Home ...

… Networks (LCN), 2010

This paper describes the design and deployment of a large scale wireless sensor network (WSN) for... more This paper describes the design and deployment of a large scale wireless sensor network (WSN) for monitoring the health of power equipment in a substation. The sensor network consists of 122 low power nodes that that are spread over an area approximately 1000 × 400 feet in size and perform monitoring of equipment such as transformers, circuit breakers, and compressors. All nodes communicate over a multihop wireless mesh network that uses a dynamic link-quality based routing protocol. A primary objective of this project is to develop effective monitoring applications for the substation using low-cost wireless sensor nodes that can sustain long periods of battery life. We study the battery consumption in the network and present a transmission scheme that conserves communication cost by enabling the sensor nodes to transmit observation samples only when their values are significantly different from those transmitted previously. Experimental results that demonstrate the performance of the sensor network for several monitoring applications are presented.