國立臺南大學教師基本資料

基本資料
姓名 陳建志
系所 電機工程學系
職稱 副教授
校內分機 7799
傳真 06-2602305
辦公室/研究室 ZC105-4
E-mail jjchen@mail.nutn.edu.tw
網址 http://home.nutn.edu.tw/jjchen
專長/研究領域 第四代無線通訊技術,第五代無線通訊技術與物聯網,行動計算,無線通訊與網路,物聯網技術與應用
 

畢業學校國別主修學門學位修業期間
國立交通大學台灣資訊工程學士1997~2001
國立交通大學台灣資訊工程碩士2001~2003
國立交通大學台灣資訊工程博士2003~2009

服務機關部門 / 系所職稱服務期間
工研院電通所約聘研究人員2001 ~ 2003
美國伊利諾大學香檳分校資訊工程學系訪問學者2007 ~ 2008
中華民國海軍陸戰隊77旅少尉排長2009 ~ 2010
國立交通大學電機工程學系博士後研究員2010 ~ 2011
國立臺南大學電子計算機中心資訊系統組組長2011 ~ 2013
國立臺南大學電機工程學系助理教授2011~2017
國立臺南大學電機工程學系副教授2017~present

著作
名稱Y.-B. Lin*, W.-R. Lai, and J.-J. Chen, “Effects of Cache Mechanism on Wireless Data Access,” IEEE Transactions on Wireless Communications, 2(6): 1247-1258, Nov. 2003.
年度2003
類別期刊論文
摘要
關鍵字
名稱J.-J Chen*, Y.-C. Tseng, and H.-W. Lee, “A Seamless Handoff Mechanism for DHCP-Based IEEE 802.11 WLANs,” IEEE Communications Letters, 11(6): 665-667, Aug. 2007.
年度2007
類別期刊論文
摘要
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名稱Y.-C. Tseng, J.-J. Chen*, and Y.-L. Cheng, “Design and Implementation of A SIP-Based Mobile and Vehicular Wireless Network with Push Mechanism,” IEEE Trans. On Vehicular Technology, 56(6): 3408-3420, Nov. 2007.
年度2007
類別期刊論文
摘要
關鍵字
名稱P.-Y. Wu, J.-J. Chen*, Y.-C. Tseng, and H.-W. Lee, “Design of QoS and Admission Control for VoIP Services over IEEE 802.11e WLANs,” Journal of Information Science and Engineering, 24(4): 1003-1022, Jul. 2008.
年度2008
類別期刊論文
摘要
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名稱J.-M. Liang*, H.-C. Wu, J.-J. Chen, and Y.-C. Tseng, “Mini-Slot Scheduling for IEEE 802.16d Chain and Grid Mesh Networks,” Computer Communications, 33(17): 2048-2056, Nov. 2010.
年度2010
類別期刊論文
摘要
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名稱J.-M. Liang*, J.-J. Chen, Y.-C. Wang, and Y.-C. Tseng, “A Cross-Layer Framework for Overhead Reduction, Traffic Scheduling, and Burst Allocation in IEEE 802.16 OFDMA Networks,” IEEE Trans. on Vehicular Technology, 60(4): 1740-1755, May 2011.
年度2011
類別期刊論文
摘要
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名稱J.-J. Chen*, L. Li, and Y.-C. Tseng, “Integrating SIP and IEEE 802.11e to Support Handoff and Multi-grade QoS for VoIP-over-WLAN Applications,” Computer Networks, 55(8): 1719-1734, Jun. 2011.
年度2011
類別期刊論文
摘要
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名稱Y.-C. Tseng, J.-J. Chen*, and Y.-C. Yang, “Managing Power Saving Classes in IEEE 802.16 Wireless MANs: A Fold-and-Demultiplex Method,” IEEE Trans. on Mobile Computing, 10(9): 1237-1247, Sept. 2011.
年度2011
類別期刊論文
摘要In IEEE 802.16, power management at the Mobile Subscriber Station (MSS) side is always an important issue. The standard defines three types of power saving classes (PSCs). A PSC can bind one or multiple traffic flows. However, given multiple flows in an MSS, the standard does not define how to form PSCs, how to organize the cooperation of multiple PSCs to obtain better energy efficiency, and how to guarantee QoS of these flows. Given a set of flows and their QoS parameters, the objective of this paper is to define multiple PSCs and their listen-and-sleep-related parameters and packet-scheduling policy such that the unavailability intervals of the MSS can be maximized and the QoS of each flow can be guaranteed. To achieve this, we propose a novel fold-and-demultiplex method for an IEEE 802.16 network with PSCs of types I and II together with an earliest-next-bandwidth-first packet scheduler. Given a set of traffic flows in an MSS, the fold-and-demultiplex method first gives each flow a tentative PSC satisfying its bandwidth requirement. Then we fold them together into one long series so as to calculate the total bandwidth requirement. Finally, we demultiplex the series into multiple PSCs, each supporting one or multiple flows. It ends up with high energy efficiency of MSSs while meets flows bandwidth requirements. Furthermore, our packet scheduler ensures that real-time flows delay constraints can be met. To the best of our knowledge, this is the first result offering bounded packet delays under MSSs sleep-and-listen behaviors.
關鍵字IEEE 802.16, link protocol, MAC protocol, packet schedule, power management, WiMAX, wireless network
名稱J.-M. Liang*, Y.-C. Wang, J.-J. Chen, J.-H. Liu, and Y.-C. Tseng, “Energy-Efficient Uplink Resource Allocation for IEEE 802.16j Transparent-Relay Networks,” Computer Networks, 55(16): 3705-3720, Nov. 2011.
年度2011
類別期刊論文
摘要The IEEE 802.16j standard is defined to enhance WiMAX networks with relay capacity. Under the transparent mode, existing studies only target at improving network throughput by increasing the transmission rates of mobile stations (MSs) and maximizing concurrent transmissions. However, using a higher transmission rate or allowing more concurrent transmissions could harm MSs in terms of their energy consumption, especially when they are battery-powered. In this paper, we consider the energy-conserved resource allocation problem in the uplink direction of an IEEE 802.16j network under the transparent mode. This problem asks how to arrange the frame usage with satisfying MSs’ demands as the constraint and minimizing their total energy consumption as the objective. We prove this problem to be NP-complete and develop two energyefficient heuristics, called demand-first allocation (DFA) and energy-first allocation (EFA) schemes. These heuristics employ a gradient-like search method to approximate the optimal solution. Specifically, DFA tries to satisfy MSs’ demands first by using as less frame space as possible. Then, with the remaining frame space, DFA tries to save MSs’ energy by lowering their transmission rates or adjusting their transmission paths. Viewed from a different perspective, EFA first allocates the frame space to MSs to consume the least energy. Since the total allocation may exceed the frame space, EFA then exploits spatial reuse and rate adjustment to pack all demands into one frame. Simulation results show that our heuristics can approximate the ideal performance bounds and save up to 90% of MSs’ energy as compared to existing results.
關鍵字broadband wireless network, energy conservation, IEEE 802.16j, resource management, transparent relay, WiMAX
名稱J.-J. Chen, S.-L. Wu*, S.-W. Wang, and Y.-C. Tseng, “Per-Flow Sleep Scheduling for Power Management in IEEE 802.16e Networks,” Computer Networks, 55(16): 3721-3733, Nov. 2011.
年度2011
類別期刊論文
摘要Power management is a critical issue in IEEE 802.16 wireless networks. In the standard, a power saving class (PSC) of type II is defined to support real-time traffic flows. It allows a flow to switch periodically between active and sleep states to save energy. However, previous studies either consider adjusting start frames of PSCs by assuming that the PSCs are already given or assume one single PSC to accommodate all flows in a mobile station, thus leading to higher energy cost. This paper proposes two "per-flow" sleep scheduling schemes, which assign one PSC to each real-time flow according to its QoS parameters. This leads to less energy consumption, more efficient use of bandwidth, and more compact listening windows. We also prove that deciding whether a given scheduling problem is solvable can be reduced to a maximum matching problem, which is computationally tractable. Simulation results show that such a per-flow scheduling does perform much closer to the active ratio lower bound and achieve higher resource utilization than previous schemes.
關鍵字IEEE 802.16, mobile communication, power saving class, quality of service (QoS), WiMAX, wireless network
名稱J.-M. Liang*, J.-J. Chen, C.-W. Liu, Y.-C. Tseng, and B.-S. Lin, “On Tile-and-Energy Allocation in OFDMA Broadband Wireless Networks,” IEEE Communications Letters, 15(12): 1284-1287, Dec. 2011.
年度2011
類別期刊論文
摘要The Orthogonal Frequency Division Multiple Access (OFDMA) technique has been widely applied in broadband wireless networks, such as IEEE 802.16 (WiMAX) and 3GPP Long Term Evolution (LTE). Existing studies have targeted at improving network throughput by increasing the transmission rates of mobile stations (MSs). Nevertheless, this is at the cost of higher energy consumption of MSs. In the letter, we consider the tile-and-energy joint allocation problem for uplink transmissions in an OFDMA wireless network. We formulate this problem as a mixed integer programming, where the objective is to minimize MSs energy consumption subject to satisfying their traffic demands. We show this to be NP-hard and develop a heuristic taking advantage of the water-filling technique. Simulation results show that the performance of our heuristic is close to the optimum, especially when the network is under non-saturated condition.
關鍵字3GPP LTE, energy conservation, IEEE 802.16, OFDMA, resource management, WiMAX
名稱J.-J. Chen* and Y.-C. Tseng, “Power Management in IEEE 802.16 Broadband Wireless Networks,” Communications of IICM, 14(3): 19-42, Sept. 2011.
年度2011
類別期刊論文
摘要In the recent years, wireless broadband access is gaining more popularity. Among all wireless data access technologies, the IEEE 802.16 wireless networks are designed to provide users a mobile and broadband wireless access in metropolitan areas. For mobile users, long device operation time is always one of the most important issues for wireless access. In the IEEE 802.16 standard, three types of power saving classes (PSCs) are defined for ?ows with different QoS characteristics. A mobile device is allowed to turn off its wireless radio when all its PSCs are in sleep states. Among the three types of PSCs, the power saving class of type II is defined to support real-time traffic flows. It allows a flow to switch periodically between active and sleep states to save energy. However, previous studies either consider adjusting start frames of PSCs by assuming that the PSCs are already given or use a single sleep pattern to accommodate all flows in a mobile station (MS) or serve multiple MSs under one base station (BS), thus leading to higher energy cost. This paper proposes three PSC management algorithms for IEEE 802.16 wireless networks. In the three schemes, two consider a BS-MS pair, one refers to multiple MSs under a BS. For single MS, we propose to use multiple PSCs to schedule the sleep of the MS such that the sleep schedule can more accurately capture the QoS of flows and make the MS sleep more. For multiple MSs, we observe that if the sleep cycles of MSs can be assigned according to their delay bounds, MSs can signi?cantly reduce their duty cycles. Therefore, we propose to schedule resources for MSs according to their QoS characteristics such that their total wake up time is minimized. These three proposed schemes lead to less energy consumption, more efficient use of bandwidth, and more compact listening windows. Moreover, they are all compatible to the standard. Simulation results verify that our algorithms incur less power consumption and leads to higher bandwidth utilization than the previous schemes.
關鍵字IEEE 802.16, Power management, Power saving class, Quality of service (QoS), WiMAX, Wireless network, Mobile communication
名稱S.-L. Wu*, J.-T. Chang, and J.-J. Chen, “Distributed Cell-centric Neighborhood-related Location Area Planning for PCS Networks,” Computer Communications, 35(1): 141-149, Jan. 2012.
年度2012
類別期刊論文
摘要?An intelligent location area planning (LAP) scheme should consider the frequent replannings of location areas (LAs) due to changes in user distribution and mobility patterns along with optimization of location management costs, including location updating and paging costs. Most schemes proposed in the literature are designed through centralized techniques, thus requiring more computing time to plan the LAs. Frequent replannings to accommodate environmental changes make the situation worse. As to the optimization of location management costs, most proposed schemes consider the inter-cell crossing rate as one of the key factors in determining the optimal partitions. In some cases, the inter-cell crossing rate may lead to an unsatisfactory outcome. Another problem is the ping-pong effect which is caused by the fixed borders between any two of LAs. In this paper, we propose a distributed cell-centric neighborhood-related LAP scheme in which each cell acts as the center of an LA and in which highly correlative neighboring cells are bundled into the LA if mobile terminals (MTs) remain within the LA long enough to reduce costs. Moreover, the ping-pong effect will be alleviated because MTs always locate at the center cell of an LA whenever a new location update is performed. Finally, the scheme can be implemented in a distributed manner so the computing time incurred by frequent replannings can be reduced. Simulation results show that our scheme indeed exhibits excellent results.
關鍵字Location area planning, Location management, Automatic reconfiguration, Mobility management, Long term evolution (LTE) networks
名稱An Energy-Efficient Sleep Scheduling with QoS Consideration in 3GPP LTE-Advanced Networks for Internet of Things
年度2013
類別期刊論文
摘要With the design of data communications in mind, 3GPP LTE-advanced (LTE-A) is probably the most promising technology for Internet of Things (IoT). For IoT applications, continuous low-rate streaming data may be reported from devices over a long period of time, imposing stringent requirements on power saving. To manage power consumption, 3GPP LTE-A has defined the discontinuous reception/transmission (DRX/DTX) mechanism to allow devices to turn off their radio interfaces and go to sleep in various patterns. Existing literature has paid much attention to evaluate the performance of DRX/DTX; however, how to tune DRX/DTX parameters to optimize energy cost is still left open. This paper addresses the DRX/DTX optimization, by asking how to maximize the sleep periods of devices while guarantee their quality-of-service (QoS), especially on the aspects of traffic bit-rate, packet delay, and packet loss rate in IoT applications. Efficient schemes to optimize DRX/DTX parameters and schedule devices packets with the base station are proposed. The key idea of our schemes is to balance the impacts between QoS parameters and DRX/DTX configurations. Simulation results show that our schemes can guarantee traffic bit-rate, packet delay, and packet loss rate while save energy of user equipments.
關鍵字Discontinuous reception/transmission (DRX/DTX), internet of things (IoT), long term evolution-advanced (LTE-advanced), power saving, quality of service, sleep scheduling.
名稱Cell-related Location Area Planning for 4G PCS Networks with Variable-order Markov Model
年度2013
類別期刊論文
摘要Location management is a critical issue in personal communication service (PCS) networks, tracking the location of user equipment (UE) with the goal of minimizing total signaling cost. Previous work can be classified into two categories: static and dynamic. Static schemes partition networks into fixed size LAs. However, these schemes are inefficient because they do not take UEs’ mobility and the call arrival rate into account. On the other hand, focusing on individual UEs, dynamic schemes have minimized the location management cost. However, they are difficult to implement because recording the individual information of numerous UEs and planning each of their LAs consume uncontrollable cost. Because of these reasons, we propose a cell-based scheme between static and dynamic schemes. Considering people usually stay in specific zones for long periods and the movement of UEs usually presents a strong moving direction in areas, this study presents a distributed algorithm by employing variable-order Markov models to find the mobility characteristic shared by UEs to plan better LAs with lower location management cost. When the order of Markov model is set to 1, our method is equal to a pure cell-centric LAP scheme; while the order of Markov model is high, it is more like a profile-based dynamic scheme. So, the setting of the order actually is a trade-off problem between the overall location management cost and the computing complexity. We present to retrieve a balance by using the expected location management cost and the number of total states of Markov models. In simulations, the origin–destination matrix (O–D matrix) from the Taipei Rapid Transit Corporation is used for representing the association between two cells. Simulation results demonstrate that the proposed scheme achieves good performance.
關鍵字Location management; Location area planning; Variable-order Markov model; Mobile computing
名稱Dynamic Cooperating Set Planning for Coordinated Multi-Point (CoMP) in LTE/LTE-Advanced Systems
年度2013
類別期刊論文
摘要Coordinated Multi-Point (CoMP) is considered as one of the most important technique in 3GPP LTE/LTE-Advanced. In CoMP, several base stations can be grouped together to form the cooperating set, where the cooperating set is used to improve the system throughput as well as the throughput of cell edge users. Most of the studies discuss static cooperating set, i.e., the size of the cooperating set is fixed, such as 3 or 7. However, when big activities occur with gathered crowds, such as gala parades and New Year’s Eve, the amount of wireless communication demands in such areas is over the capacity of serving base stations. In this case, the static cooperating set can bring only limited help and fails to adapt to the actual conditions. Moreover, additional communication overhead among cells is introduced but futile. In this paper, we propose the dynamic cooperating set to solve above problem. The proposed method takes the actual traffic requirement and geographical area into consideration to form dynamic cooperating set to offload the wireless communication demand. Dynamic cooperating set can not only enhance the system and cell edge throughput but also utilize the radio resource in an efficient way. The latter avoids unlimited expansion of the cooperating set. Simulation results show that the throughput of our method is 1.19 and 1.27 times of the static CoMP scheme and no CoMP scheme, respectively.
關鍵字CoMP, LTE, FFR, resource management, OFDMA, DCS
名稱A Green Handoff Method for 4G OFDMA Macrocell-femtocell Heterogeneous Networks
年度2013
類別期刊論文
摘要With the increased demand of broadband wireless communication networks, users have an increasing need of the wireless broadband service coverage and the wireless access quality. To solve this problem, several novel technologies are proposed. One of these technologies is femtocells. A femtocell can be used to increase the coverage of wireless broadband service indoors or at hotspots and raise both data transmission rate and access quality. Although the use of femtocells can greatly benefit, deploying large number of femtocells consumes tremendous energy. In order to respond to the problem of global climate change, energy saving is always an important issue. This paper discusses how to minimize the energy consumption of femtocells, optimize the energy efficiency of femtocells, but still provide both the same data transmission rate and wireless broadband service coverage. In this paper, we propose a green handover and dynamic femtocell wake up approach. In default, femtocells are stay in idle mode when no one connecting to it. They transit to active mode only when detecting User Equipments (UEs) and the power efficiency of using the femtocell to transmit data is better than the macrocell. By this way, not only users can benefit from the femtocells but also femtocells can reduce unnecessary power consumption. Simulation results show that, in bot 3G/4G wireless communication networks, our method performs better than the previous methods in power consumption, power efficiency and throughput.
關鍵字femtocell, green handoff, OFDMA, LTE/LTE-A, energy efficiency, heterogeneous networks
名稱Design a Cross-layer Uplink Green Resource and Power Allocation Method over LTE-A Relay Networks
年度2014
類別期刊論文
摘要在 LTE-A 的架構中,中繼式節點被提出來可以增強基地台的覆蓋率、節省行動裝置的耗電量、提供高速的資料傳輸並解決通訊空洞問題。然而,對使用者來說,LTE-A 使用高的傳輸資料速率將產生更多的能源損耗,尤其行動裝置是由電池供電的,續航力對裝置而言非常重要。在本文中,我們考慮如何在 LTE-A 中繼式網路架構中妥善分配上行資源和安排手機傳輸功率。我們的目標是在保證服務品質的情形下,使得所有的使用者裝置(User Equipments,UEs)所消耗的總能量最少。我們證明這是一個 NP-complete 問題,所以我們提出一個有效率的方法來解決這個問題。模擬結果顯示我們的方法能有效減少使用者裝置的電量消耗並保證他們的服務品質。
關鍵字進階長期演進技術、能源效率、資源分配、中繼式網路、綠能通訊。
名稱Design and Realization of an NFC-driven Smart Home System to Support Intruder Detection and Social Network Integration
年度2015
類別期刊論文
摘要Internet of thing (IoT) emerges as a possible solution to realize a smart life in the modern age. In this article, we design and realize a novel NFC-driven Smart Home System for IoT, which integrates the Wireless Sensor Network (WSN), Social Networks, and the Cloud Computing. Near Field Communication (NFC) technology provides a way for users to exchange information between them and the system by simply contacting. So, we propose to use NFC as the system drive in the architecture, such that users can intuitively interact with the system and deliver their intentions. Then, the corresponding service over the system will control or adjust the “things” at home to fit users’ needs. Furthermore, the proposed system provides a platform for developers to easily and rapidly implement their smart home related services. In the system, WSN sensing and control, NFC communications and identification, user profile management and preference analysis, and social network integration are all provide as platform services. We will show how the system works for home automation, intruder detection, and social network sharing.
關鍵字Cloud computing, home automation, intruder detection, near field communication, security monitoring, social networks, wireless sensor network
名稱Distributed object tracking using moving trajectories in wireless sensor networks
年度2016
類別期刊論文
摘要Most recent research on object tracking sensor networks has focused on collecting all data from the sensor network into the sink, which delivers the predicted locations to the corresponding nodes in order to accurately predict object movement. The communication cost of this centralized scenario is higher than that of a distributed method. Centralized data collection affects the freshness of the data and increases latency in movement trajectory prediction. In addition, due to the large amount of packets being sent and received, sensor node energy is quickly exhausted. Although this data collection method might result in higher accuracy for prediction, the sensor network lifetime is not reduced. In this paper, a distributed object tracking method is proposed using the network structure of convex polygons, called faces. The nodes in the faces cooperate to find the trajectories of an object and then these trajectories are used to predict the objects movement. The proposed method, based on trajectory tree construction, can reduce both the storage space of collected trajectories and the time spent on trajectory prediction analysis. Simulations show that the proposed method can reduce the energy consumption of the nodes and make prediction of nodes moving direction accurately than the existing approaches.
關鍵字Data mining, Object tracking, Sensor networks, Trajectory, Wireless networks
名稱Two-Phase Multicast DRX Scheduling for 3GPP LTE-Advanced Networks
年度2016
類別期刊論文
摘要For next-generation wireless communications, the 3GPP Long Term Evolution-Advanced (LTE-A) is the most promising technology which provides transmission rate up to 1 Gbps and supports various broadband multimedia services, such as IPTV and Voice/Video-over-IP services. To reduce the energy consumption of user equipments (UEs), the LTE-A standard defines the Discontinuous Reception Mechanism (DRX) to allow UEs to turn off their radio interfaces and go to sleep when no data needs to be received. However, how to optimally configure DRX for UEs is still left as an open issue. In this paper, we address the DRX optimization problem for multicast services. This problem asks how to guarantee the quality of service (QoS) of the multicast streams under the Evolved Node B (eNB) while minimizing the UEs’ wake-up time. We prove this problem to be NP-complete and propose an energy-efficient heuristic. This heuristic consists of two phases. The first phase tries to aggregate the required bandwidth of the multicast streams for UEs to reduce their wake-up periods. The second phase further minimizes UEs’ unnecessary wake-up periods by optimizing their DRX configurations. Extensive simulation results show that our scheduling is close to the optimum in most cases.
關鍵字Discontinuous Reception Mechanism (DRX), Energy Saving, Long Term Evolution-Advanced (LTE-A), Multimedia Broadcast Multicast Service (MBMS), Quality of Service (QoS)
名稱A Novel Energy Saving Resource Allocation Scheme in LTE-A Relay Networks
年度2016
類別期刊論文
摘要The relay node (RN) in Long-Term Evolution-Advanced (LTE-A) networks is used to enhance the coverage of high data rate and solve the coverage hole problem. Considering the limited energy nature of User Equipment (UE), connecting to the RN instead of Evolved Node B (eNB) is a better choice for cell-edge UE items. In this paper, on the premise of compatibility to the LTE-A resource allocation specification, we discuss an uplink radio resource, uplink path, modulation and coding scheme (MCS), and transmit power allocation problem for energy conservation in LTE-A relay networks. The objective is to minimize the total energy consumption of UE items while guaranteeing the constraints of UE items’ quality of service (QoS), bit-error-rate (BER), total system resource, and maximum transmit power. Since the problem is NP-complete and the scheduling period in LTE-A is short (the subframe length is only 1 ms), we propose an efficient method to solve the problem. The complexity analysis shows the time complexity of the proposed heuristics is 𝑂(𝑛^2). Simulation results demonstrate that our algorithmcan effectively reduce the energy consumption of UE items and guarantee users’ service quality.
關鍵字LTE-A, energy conservation, resource management, relays
名稱Energy Efficient Dynamic Network Configuration in Two-Tier LTE/LTE-A Cellular Networks
年度2016
類別期刊論文
摘要With the increasing demand of broadband wireless communication networks, users have an in-creasing need of the wireless broadband service coverage and the wireless access quality. To alleviate this problem, several novel techniques are proposed. One of these techniques is femtocells. A femtocell can be used to increase the coverage of wireless broadband service indoors or at hotspots and raise both data trans-mission rate and access quality. Although the use of femtocells can greatly benefit, deploying large number of femtocells consumes tremendous energy. In order to respond to the problem of global climate change, energy saving is an important issue. This paper discusses how to minimize the energy consumption of femtocells and optimize the energy efficiency of networks while still providing both the same data transmission rate and wireless broadband service coverage. In this work, considering path loss, modulation and coding schemes (MCSs), bit-error-rate (BER) and group mobility, we propose a green handover and dynamic femtocell wake up approach. In default, femtocells are stay in “idle mode” when no user equipment (UE) con-necting to it. A femtocell transits to active mode only when detecting UEs and the efficiency of using the femtocell is better than the macrocell. By this way, not only users can benefit from the femtocells but also femtocells can reduce unnecessary power consumption. Simulation results show that our method performs better than the previous methods in power consumption, energy efficiency and throughput in both 3G/4G wireless communication networks.
關鍵字energy-efficiency, femtocell, green communication networks, handover, heterogeneous networks, LTE/LTE-A, Orthogonal Frequency Division Multiple Access (OFDMA)