Nga Dinh - Academia.edu (original) (raw)
Papers by Nga Dinh
2020 IEEE Eighth International Conference on Communications and Electronics (ICCE), 2021
Sustainable operation is one of the key challenges for Internet of Thing (IoT) sensor nodes becau... more Sustainable operation is one of the key challenges for Internet of Thing (IoT) sensor nodes because they are usually powered by limited battery power. Many IoT applications require the sensor nodes to operate reliably and consistently for a long period of time. Approaches to prolong the lifespan of sensor nodes include sleep-mode mechanism, harvesting energy from the environment (such as light, wind, water mills…) and from a dedicated power supply. Energy harvesting (EH) from nature has emerged as especially promising because it is clean, free and does not interrupt operation of the nodes. Long-Range Wide Area Network (LoRaWAN) can provide low-power, low-cost, and long-range communication for IoT nodes. In LoRaWAN, a node can extend its lifetime by using a deep-sleep mechanism. Even though the lifetime can be extended by the deep-sleep mechanism, it is expected to further extend the lifespan to reduce or eliminate the replacement of outage devices. Due to the potentials of LoRaWAN for IoT and the importance of EH approach to provide sustainable operation for IoT nodes, this paper focuses on using both EH and the deep-sleep mechanism in LoRaWAN to significantly prolong the lifetime of sensor nodes. In particular, the paper proposes a new power metric, called power gradient, to evaluate power performance of the network. The paper also estimates the performance of EH-based sensor nodes in terms of power gradient and lifetime. The proposed metric provides some insights on parameters configuration to achieve the desirable lifetime of EH-based nodes under LoRaWAN.
2020 16th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2020
Wireless powered communication networks (WPCN) which allow an energy source (ES) to wirelessly tr... more Wireless powered communication networks (WPCN) which allow an energy source (ES) to wirelessly transfer its power to a wireless device (WD) is becoming a promising technology in modern wireless networks. Besides extending network longevity, WPCN eliminates the need for frequent manual battery replacement or recharging. Even WPCN is a potential solution, how to optimize network lifetime to guarantee network substantiality and reliability is challenging. This problem has not yet been considered carefully in literature. In addition, existing related works do not consider both uplink and downlink traffic which directly impact device lifetime as well as network lifetime. This paper, therefore, deals with the problem of optimizing network lifetime by appropriately scheduling transmitted power from an ES to each WD. To this end, the paper first proposes models for device lifetime and network lifetime. Based on the models, the strategy to optimize network lifetime is derived. The paper then proposes a power scheduling algorithm performed at an ES to maximize network lifetime under several network conditions. The proposed algorithm takes into account bi-directional traffic at each WD. The proposed models and the performance of power scheduling algorithm are verified by simulations. The paper is an useful guideline to assess reliability duration of the network and provides several directions to ensure network reliability and substantiality.
The Internet of Things (IoT) is going to be a market-changing force for a variety of real-time ap... more The Internet of Things (IoT) is going to be a market-changing force for a variety of real-time applications such as e-healthcare, home automation, environmental monitoring, and industrial automation. Low power wireless communication protocols offering long lifetime and high reliability such as the IEEE 802.15.4 standard have been a key enabling technology for IoT deployments and are deployed for home automation recently. The issues of the IEEE 802.15.4 networks have moved from theory to real world deployments. The work presented herein intends to demonstrate the use of the IEEE 802.15.4 standard in recent IoT commercial products for smart home applications: the Smart Home Starter Kit. The contributions of the paper are twofold. First, the paper presents how the IEEE 802.15.4 standard is employed in Smart Home Starter Kit. In particular, network topology, network operations, and data transfer mode are investigated. Second, network performance metrics such as end-to-end (E2E) delay an...
IECON 2021 – 47th Annual Conference of the IEEE Industrial Electronics Society, 2021
A wireless sensor network (WSN) depends on energy to operate and considerable efforts have been d... more A wireless sensor network (WSN) depends on energy to operate and considerable efforts have been devoted to extend its operational lifetime. Energy harvesting (EH) has emerged as one promising approach to prolong the lifetime of a WSN without interrupting its operations. In an EH-WSN, sensor nodes typically have batteries being charged with energy harvested from ambient environments such as wind, solar, water mills etc. However, uncertainties remain about when and how much energy can be harvested over time from the environments and about traffic fluctuation at each node. Unfortunately, existing works on EH-WSN are limited in evaluating the impacts of these factors and the number of the nodes in an EH-WSN on its key performance metrics. This paper, therefore, presents a general method and a practical implementation of a node capable of harvesting solar energy in an EH-WSN. The paper then evaluates the performance of the EH-WSN. Explicit mathematical expressions define models for network operational time, throughput and reliability of the EH-WSN and simulations are used to validate the models. Influential factors are energy arrival rate, traffic rate at each node and the number of nodes in an EH-WSN. The results document that the analytical models and simulations correspond.
International Journal of Electrical and Computer Engineering (IJECE), 2016
This paper aims to develop several mathematical models to study medium access control (MAC) proto... more This paper aims to develop several mathematical models to study medium access control (MAC) protocol in the IEEE 802.15.4 beacon-enabled mode with star topology. In particular, the MAC protocol which employs a slotted carrier-sense multiple access with collision avoidance (CSMA/CA) algorithm used in the contention access period (CAP) of a superframe is modelled. The analysis studies the effectiveness of the CSMA/CA algorithm and provides explicit mathematical expressions for power consumption, access delay, and data frame drop probability. The proposed models precisely follow CSMA/CA algorithm in MAC protocol of beacon-enabled mode and differ from those previously published in the literature as 1) they are derived based on data frame generation rate of end devices, 2) they provide a completed expression for frame access delay, and 3) lowpower states of end devices are considered for power efficiency evaluations. The paper shows how power consumption of end devices is improved on the...
IEEE Journal on Selected Areas in Communications, 2014
ABSTRACT
2014 IEEE International Conference on Communications (ICC), 2014
ABSTRACT
2013 IEEE International Conference on Communications Workshops (ICC), 2013
ABSTRACT
Journal of Physics: Conference Series, 2009
... characteristics Dinh Sy Hien 1 , Nguyen Thi Luong 1 , Thi Tran Anh Tuan 1 and Dinh Viet Nga 1... more ... characteristics Dinh Sy Hien 1 , Nguyen Thi Luong 1 , Thi Tran Anh Tuan 1 and Dinh Viet Nga 1 1 HCM University of Natural Sciences, 227 Nguyen Van Cu Street, 5 District, Ho Chi Minh City, Vietnam E-mail: vietnga704@yahoo.com Abstract. ...
IET Communications, 2011
In Mobile WiMAX, the power saving mechanism (PSM), which operates alternately in sleep and awake ... more In Mobile WiMAX, the power saving mechanism (PSM), which operates alternately in sleep and awake modes, works to extend the lifetime of mobile stations (MSs), though it concurrently induces a medium access control (MAC) service data unit (SDU) response delay. In this paper, we derive the analytical models for two of the most important performance metrics: the average power consumption and the average MAC SDU response delay of an MS in sleep mode. These metrics are given as a function of the sleep mode system parameters: initial sleep window T min and final sleep window T max. Based on these models, we show that a tradeoff relationship exists between them. We then propose an optimized power-saving mechanism (OPSM) that jointly determines the optimal T min and T max in order to minimize the power consumption under a given MAC SDU response delay constraint. Through both numerical analyses and subsequent simulations, we show that the OPSM effectively minimizes power consumption of an MS in its sleep mode while guaranteeing the MAC SDU response delay constraint.
2012 IEEE Global Communications Conference (GLOBECOM), 2012
ABSTRACT Reducing power consumption in access networks has become an increasingly important desig... more ABSTRACT Reducing power consumption in access networks has become an increasingly important design goal due to increased concerns for both global warming and network operation costs. Although passive optical networks (PONs) consume the least power among all access network technologies, it is desirable to further reduce PON's power consumption, especially when the line rate is being increased to 10Gbps (10G) and wider deployment is underway. Generally, an effective approach to reduce power consumption is to use sleep-mode operation where functionality is powered off during periods of idleness. This paper therefore proposes a sleep-mode based power saving protocol applied to an optical line terminal (OLT) and optical network units (ONUs) to implement ONU power saving in 10G-Ethernet-PON (10G-EPON) systems. The proposed protocol explicitly distinguishes sleep-, listen-, and awake- states with different power consumption levels. In addition, the paper proposes analytical models for ONU power consumption and response delay to evaluate performance of the proposed power saving protocol. The simulations show that the proposed protocol can significantly improve ONU power saving. The validity of the numerical models is also confirmed by extensive simulations.
2013 IEEE Global Communications Conference (GLOBECOM), 2013
ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks in... more ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks include the use of cyclic sleep modes to more effectively scale energy consumption with activity. This paper analyzes a probing-based cyclic sleep mode mechanism that is applied to the downstream of a passive optical network. The analysis studies the effectiveness of the sleep mode mechanism and provides explicit mathematical expressions for the power consumption and packet response delay in the optical network unit (ONU) at the customer premises, and the amount of buffered traffic per ONU in the optical line terminal at the central office. The analytical results are confirmed and complemented by numerical simulations, and used to provide guidelines for selecting sleep mode configuration parameters.
Studies in Computational Intelligence, 2011
In Mobile WiMAX systems, a power saving mechanism, which operates using sleep- and wake- modes, e... more In Mobile WiMAX systems, a power saving mechanism, which operates using sleep- and wake- modes, extends the battery lifetime of a Mobile Station (MS) but at the expense of the frame response delay. These two performance metrics, power consumption and delay, are reciprocally affected by sleep mode parameters such as initial sleep window Tmin, and final sleep window Tmax. This
2013 IEEE Global Communications Conference (GLOBECOM), 2013
ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks in... more ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks include the use of cyclic sleep modes to more effectively scale energy consumption with activity. This paper analyzes a probing-based cyclic sleep mode mechanism that is applied to the downstream of a passive optical network. The analysis studies the effectiveness of the sleep mode mechanism and provides explicit mathematical expressions for the power consumption and packet response delay in the optical network unit (ONU) at the customer premises, and the amount of buffered traffic per ONU in the optical line terminal at the central office. The analytical results are confirmed and complemented by numerical simulations, and used to provide guidelines for selecting sleep mode configuration parameters.
2020 IEEE Eighth International Conference on Communications and Electronics (ICCE), 2021
Sustainable operation is one of the key challenges for Internet of Thing (IoT) sensor nodes becau... more Sustainable operation is one of the key challenges for Internet of Thing (IoT) sensor nodes because they are usually powered by limited battery power. Many IoT applications require the sensor nodes to operate reliably and consistently for a long period of time. Approaches to prolong the lifespan of sensor nodes include sleep-mode mechanism, harvesting energy from the environment (such as light, wind, water mills…) and from a dedicated power supply. Energy harvesting (EH) from nature has emerged as especially promising because it is clean, free and does not interrupt operation of the nodes. Long-Range Wide Area Network (LoRaWAN) can provide low-power, low-cost, and long-range communication for IoT nodes. In LoRaWAN, a node can extend its lifetime by using a deep-sleep mechanism. Even though the lifetime can be extended by the deep-sleep mechanism, it is expected to further extend the lifespan to reduce or eliminate the replacement of outage devices. Due to the potentials of LoRaWAN for IoT and the importance of EH approach to provide sustainable operation for IoT nodes, this paper focuses on using both EH and the deep-sleep mechanism in LoRaWAN to significantly prolong the lifetime of sensor nodes. In particular, the paper proposes a new power metric, called power gradient, to evaluate power performance of the network. The paper also estimates the performance of EH-based sensor nodes in terms of power gradient and lifetime. The proposed metric provides some insights on parameters configuration to achieve the desirable lifetime of EH-based nodes under LoRaWAN.
2020 16th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 2020
Wireless powered communication networks (WPCN) which allow an energy source (ES) to wirelessly tr... more Wireless powered communication networks (WPCN) which allow an energy source (ES) to wirelessly transfer its power to a wireless device (WD) is becoming a promising technology in modern wireless networks. Besides extending network longevity, WPCN eliminates the need for frequent manual battery replacement or recharging. Even WPCN is a potential solution, how to optimize network lifetime to guarantee network substantiality and reliability is challenging. This problem has not yet been considered carefully in literature. In addition, existing related works do not consider both uplink and downlink traffic which directly impact device lifetime as well as network lifetime. This paper, therefore, deals with the problem of optimizing network lifetime by appropriately scheduling transmitted power from an ES to each WD. To this end, the paper first proposes models for device lifetime and network lifetime. Based on the models, the strategy to optimize network lifetime is derived. The paper then proposes a power scheduling algorithm performed at an ES to maximize network lifetime under several network conditions. The proposed algorithm takes into account bi-directional traffic at each WD. The proposed models and the performance of power scheduling algorithm are verified by simulations. The paper is an useful guideline to assess reliability duration of the network and provides several directions to ensure network reliability and substantiality.
The Internet of Things (IoT) is going to be a market-changing force for a variety of real-time ap... more The Internet of Things (IoT) is going to be a market-changing force for a variety of real-time applications such as e-healthcare, home automation, environmental monitoring, and industrial automation. Low power wireless communication protocols offering long lifetime and high reliability such as the IEEE 802.15.4 standard have been a key enabling technology for IoT deployments and are deployed for home automation recently. The issues of the IEEE 802.15.4 networks have moved from theory to real world deployments. The work presented herein intends to demonstrate the use of the IEEE 802.15.4 standard in recent IoT commercial products for smart home applications: the Smart Home Starter Kit. The contributions of the paper are twofold. First, the paper presents how the IEEE 802.15.4 standard is employed in Smart Home Starter Kit. In particular, network topology, network operations, and data transfer mode are investigated. Second, network performance metrics such as end-to-end (E2E) delay an...
IECON 2021 – 47th Annual Conference of the IEEE Industrial Electronics Society, 2021
A wireless sensor network (WSN) depends on energy to operate and considerable efforts have been d... more A wireless sensor network (WSN) depends on energy to operate and considerable efforts have been devoted to extend its operational lifetime. Energy harvesting (EH) has emerged as one promising approach to prolong the lifetime of a WSN without interrupting its operations. In an EH-WSN, sensor nodes typically have batteries being charged with energy harvested from ambient environments such as wind, solar, water mills etc. However, uncertainties remain about when and how much energy can be harvested over time from the environments and about traffic fluctuation at each node. Unfortunately, existing works on EH-WSN are limited in evaluating the impacts of these factors and the number of the nodes in an EH-WSN on its key performance metrics. This paper, therefore, presents a general method and a practical implementation of a node capable of harvesting solar energy in an EH-WSN. The paper then evaluates the performance of the EH-WSN. Explicit mathematical expressions define models for network operational time, throughput and reliability of the EH-WSN and simulations are used to validate the models. Influential factors are energy arrival rate, traffic rate at each node and the number of nodes in an EH-WSN. The results document that the analytical models and simulations correspond.
International Journal of Electrical and Computer Engineering (IJECE), 2016
This paper aims to develop several mathematical models to study medium access control (MAC) proto... more This paper aims to develop several mathematical models to study medium access control (MAC) protocol in the IEEE 802.15.4 beacon-enabled mode with star topology. In particular, the MAC protocol which employs a slotted carrier-sense multiple access with collision avoidance (CSMA/CA) algorithm used in the contention access period (CAP) of a superframe is modelled. The analysis studies the effectiveness of the CSMA/CA algorithm and provides explicit mathematical expressions for power consumption, access delay, and data frame drop probability. The proposed models precisely follow CSMA/CA algorithm in MAC protocol of beacon-enabled mode and differ from those previously published in the literature as 1) they are derived based on data frame generation rate of end devices, 2) they provide a completed expression for frame access delay, and 3) lowpower states of end devices are considered for power efficiency evaluations. The paper shows how power consumption of end devices is improved on the...
IEEE Journal on Selected Areas in Communications, 2014
ABSTRACT
2014 IEEE International Conference on Communications (ICC), 2014
ABSTRACT
2013 IEEE International Conference on Communications Workshops (ICC), 2013
ABSTRACT
Journal of Physics: Conference Series, 2009
... characteristics Dinh Sy Hien 1 , Nguyen Thi Luong 1 , Thi Tran Anh Tuan 1 and Dinh Viet Nga 1... more ... characteristics Dinh Sy Hien 1 , Nguyen Thi Luong 1 , Thi Tran Anh Tuan 1 and Dinh Viet Nga 1 1 HCM University of Natural Sciences, 227 Nguyen Van Cu Street, 5 District, Ho Chi Minh City, Vietnam E-mail: vietnga704@yahoo.com Abstract. ...
IET Communications, 2011
In Mobile WiMAX, the power saving mechanism (PSM), which operates alternately in sleep and awake ... more In Mobile WiMAX, the power saving mechanism (PSM), which operates alternately in sleep and awake modes, works to extend the lifetime of mobile stations (MSs), though it concurrently induces a medium access control (MAC) service data unit (SDU) response delay. In this paper, we derive the analytical models for two of the most important performance metrics: the average power consumption and the average MAC SDU response delay of an MS in sleep mode. These metrics are given as a function of the sleep mode system parameters: initial sleep window T min and final sleep window T max. Based on these models, we show that a tradeoff relationship exists between them. We then propose an optimized power-saving mechanism (OPSM) that jointly determines the optimal T min and T max in order to minimize the power consumption under a given MAC SDU response delay constraint. Through both numerical analyses and subsequent simulations, we show that the OPSM effectively minimizes power consumption of an MS in its sleep mode while guaranteeing the MAC SDU response delay constraint.
2012 IEEE Global Communications Conference (GLOBECOM), 2012
ABSTRACT Reducing power consumption in access networks has become an increasingly important desig... more ABSTRACT Reducing power consumption in access networks has become an increasingly important design goal due to increased concerns for both global warming and network operation costs. Although passive optical networks (PONs) consume the least power among all access network technologies, it is desirable to further reduce PON's power consumption, especially when the line rate is being increased to 10Gbps (10G) and wider deployment is underway. Generally, an effective approach to reduce power consumption is to use sleep-mode operation where functionality is powered off during periods of idleness. This paper therefore proposes a sleep-mode based power saving protocol applied to an optical line terminal (OLT) and optical network units (ONUs) to implement ONU power saving in 10G-Ethernet-PON (10G-EPON) systems. The proposed protocol explicitly distinguishes sleep-, listen-, and awake- states with different power consumption levels. In addition, the paper proposes analytical models for ONU power consumption and response delay to evaluate performance of the proposed power saving protocol. The simulations show that the proposed protocol can significantly improve ONU power saving. The validity of the numerical models is also confirmed by extensive simulations.
2013 IEEE Global Communications Conference (GLOBECOM), 2013
ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks in... more ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks include the use of cyclic sleep modes to more effectively scale energy consumption with activity. This paper analyzes a probing-based cyclic sleep mode mechanism that is applied to the downstream of a passive optical network. The analysis studies the effectiveness of the sleep mode mechanism and provides explicit mathematical expressions for the power consumption and packet response delay in the optical network unit (ONU) at the customer premises, and the amount of buffered traffic per ONU in the optical line terminal at the central office. The analytical results are confirmed and complemented by numerical simulations, and used to provide guidelines for selecting sleep mode configuration parameters.
Studies in Computational Intelligence, 2011
In Mobile WiMAX systems, a power saving mechanism, which operates using sleep- and wake- modes, e... more In Mobile WiMAX systems, a power saving mechanism, which operates using sleep- and wake- modes, extends the battery lifetime of a Mobile Station (MS) but at the expense of the frame response delay. These two performance metrics, power consumption and delay, are reciprocally affected by sleep mode parameters such as initial sleep window Tmin, and final sleep window Tmax. This
2013 IEEE Global Communications Conference (GLOBECOM), 2013
ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks in... more ABSTRACT Recent standardization efforts to reduce power consumption in optical access networks include the use of cyclic sleep modes to more effectively scale energy consumption with activity. This paper analyzes a probing-based cyclic sleep mode mechanism that is applied to the downstream of a passive optical network. The analysis studies the effectiveness of the sleep mode mechanism and provides explicit mathematical expressions for the power consumption and packet response delay in the optical network unit (ONU) at the customer premises, and the amount of buffered traffic per ONU in the optical line terminal at the central office. The analytical results are confirmed and complemented by numerical simulations, and used to provide guidelines for selecting sleep mode configuration parameters.