Chun Nie | New York University (original) (raw)
Papers by Chun Nie
IEEE Transactions on Vehicular Technology, 2013
Eurasip Journal on Wireless Communications and Networking, 2006
This paper addresses cross-layer quality-of-service (QoS) provisioning in the uplink of CDMA cell... more This paper addresses cross-layer quality-of-service (QoS) provisioning in the uplink of CDMA cellular mobile networks. Each mobile can take up to four UMTS traffic classes in our model. At the data link layer and the network layer, the QoS performances are defined in terms of signal-to-interference-plus-noise ratio and outage probability, and packet loss rate and delay, respectively. A call admission control scheme which fulfills these QoS metrics is developed to maximize the system capacity. The novelty of this paper is that the effect of the lengthening of the on-periods of non-real-time traffic classes is investigated by using the Go-Back-N automatic retransmission request mechanism with finite buffer size and limited number of retransmissions in the event of transmission errors. Simulation results for a specific example demonstrate the reasonableness of the analytical formulation. and ultra-wideband wireless mobile multimedia networks. His areas of research are in the medium access control, resource allocation with quality-of-service constraints, traffic policing with heterogeneous traffic, and cross-layer design. He is a Senior Member of the IEEE. He was on the Technical Program Committee of the IEEE WCNC
European Journal of Operational Research, 2008
... At the connection level, we present approximate analytical formulations of virtual partitioni... more ... At the connection level, we present approximate analytical formulations of virtual partitioning (VP) resource ... Finally, with cross-layer optimization, system utilization is maximized subjecting to the QoS ... 1 between the WCDMA wireless network and the wireline DiffServ network. ...
In this paper, we address the data link layer quality of service (QoS) issue by investigating the... more In this paper, we address the data link layer quality of service (QoS) issue by investigating the outage probabilities for multi-connection multiclass services in the uplink of a wideband CDMA cellular mobile network. Four Universal Mobile Telecommunications System (UMTS) QoS classes are served within each mobile user simultaneously. Each class has different QoS constraints. Assuming perfect power control, a power allocation scheme is designed to fulfill the desired received powers for all traffic classes. The outage probability is formulated for each mobile user with its traffic classes in terms of bit error rate (BER) and signal-to-interference-plus-noise ratio (SINR). In addition, an admission region, satisfying the outage probability requirements of all mobile users, is computed.
WiMAX technology, based on IEEE 802.16 standard, is a promising broadband wireless technology for... more WiMAX technology, based on IEEE 802.16 standard, is a promising broadband wireless technology for future 4G network. WiMAX provides radio access with centralized control, where bandwidth resources are managed and allocated by base station (BS) for both uplink (UL) and downlink (DL). Current WiMAX standard defines several bandwidth request (BWReq) mechanisms to serve a variety of applications, which however may not be efficient for on-off bursty traffic patterns. In this paper, we propose a novel adaptive polling service (aPS), with the advantage of significantly reducing the signaling overhead associated with the bandwidth request process without compromising the delay performance of real-time applications. Extensive simulations demonstrate that aPS outperforms existing scheduling services in terms of overall efficiency for a wide range of applications.
This contribution proposes cooperative MIMO with randomized distributed space-time coding (R-DSTC... more This contribution proposes cooperative MIMO with randomized distributed space-time coding (R-DSTC) for the 802.16m system description document (SDD).
IEEE Transactions on Wireless Communications, 2012
Relay-assisted cooperative wireless communication has been shown to have significant performance ... more Relay-assisted cooperative wireless communication has been shown to have significant performance gains over the legacy direct transmission scheme. Compared with single relay based cooperation schemes, utilizing multiple relays further improves the reliability and rate of transmissions. Distributed space-time coding (DSTC), as one of the schemes to utilize multiple relays, requires tight coordination between relays and does not perform well in a distributed environment with mobility. In this paper, a cooperative medium access control (MAC) layer protocol, called STiCMAC, is designed to allow multiple relays to transmit at the same time in an IEEE 802.11 network.
Computing Research Repository, 2011
Relay-assisted cooperative wireless communication has been shown to have significant performance ... more Relay-assisted cooperative wireless communication has been shown to have significant performance gains over the legacy direct transmission scheme. Compared with single relay based cooperation schemes, utilizing multiple relays further improves the reliability and rate of transmissions. Distributed space-time coding (DSTC), as one of the schemes to utilize multiple relays, requires tight coordination between relays and does not perform well in a distributed environment with mobility. In this paper, a cooperative medium access control (MAC) layer protocol, called \emph{STiCMAC}, is designed to allow multiple relays to transmit at the same time in an IEEE 802.11 network. The transmission is based on a novel DSTC scheme called \emph{randomized distributed space-time coding} (\emph{R-DSTC}), which requires minimum coordination. Unlike conventional cooperation schemes that pick nodes with good links, \emph{STiCMAC} picks a \emph{transmission mode} that could most improve the end-to-end data rate. Any station that correctly receives from the source can act as a relay and participate in forwarding. The MAC protocol is implemented in a fully decentralized manner and is able to opportunistically recruit relays on the fly, thus making it \emph{robust} to channel variations and user mobility. Simulation results show that the network capacity and delay performance are greatly improved, especially in a mobile environment.
A key technology in cooperative communications is distributed space-time coding (DSTC) which achi... more A key technology in cooperative communications is distributed space-time coding (DSTC) which achieves spatial diversity gain from multiple relays. A novel DSTC, called randomized distributed space-time coding (R-DSTC), shows considerable advantages over a regular DSTC in terms of system complexity. In this paper, we exploit the benefits of R-DSTC physical (PHY) layer and develop a distributed and opportunistic medium access control (MAC) layer protocol for R-DSTC deployment in an IEEE 802.11 wireless local area network (WLAN). Unlike other cooperative MAC designs, in our proposed PHY-MAC cross-layer framework, there is no need to decide which stations will serve as relays before each packet transmission. Instead, the MAC layer opportunistically recruits relay stations on the fly; any station that receives a packet from the source correctly forwards it to the destination. Through extensive simulations, we validate the efficiency of our MAC layer protocol and demonstrate that network capacity and delay performance is considerably improved with respect to legacy IEEE 802.11g network.
In next generation broadband wireless networks, the orthogonal frequency division multiple access... more In next generation broadband wireless networks, the orthogonal frequency division multiple access (OFDMA) technique provides a flexible physical interface for mobile users (MS) to share the radio resources. Since OFDMA allows MSs in different cells to reuse the same frequency subchannels to increase network spectrum utilization, MSs at the edge of a cell suffer from severe inter-cell interference from co-channel MSs in the neighboring cells. In WiMAX and LTE networks, fractional frequency reuse (FFR) is employed to mitigate the interference for edge users, but may incur a cost in terms of a lower overall spectrum utilization. In this paper, we propose a novel frequency planning scheme to improve the signal-to-interference (SIR) ratio of edge MSs in a multi-cell OFDMA system. A cell is partitioned in a way that minimizes the interference to the edge areas while sustaining a full frequency reuse factor (FRF) for each cell. Simulation results show that our scheme substantially outperforms FFR methods in terms of SIR under the condition of full frequency reuse and high traffic load.
The IEEE 802.16/WiMAX standard has fully embraced multi-antenna technology and can, thus, deliver... more The IEEE 802.16/WiMAX standard has fully embraced multi-antenna technology and can, thus, deliver robust and high transmission rates and higher system capacity. Nevertheless, due to its inherent form-factor constraints and cost concerns, a WiMAX mobile station (MS) should preferably contain fewer radio frequency (RF) chains than antenna elements. This is because RF chains are often substantially more expensive than antenna elements. Thus, antenna selection, wherein a subset of antennas is dynamically selected to connect to the limited RF chains for transceiving, is a highly appealing performance enhancement technique for multi-antenna WiMAX terminals. In this paper, a novel antenna selection protocol tailored for next-generation IEEE 802.16 mobile stations is proposed. As demonstrated by the extensive OPNET simulations, the proposed protocol delivers a significant performance improvement over conventional 802.16 terminals that lack the antenna selection capability. Moreover, the new protocol leverages the existing signaling methods defined in 802.16, thereby incurring a negligible signaling overhead and requiring only diminutive modifications of the standard. To the best of our knowledge, this paper represents the first effort to support antenna selection capability in IEEE 802.16 mobile stations.
Cooperative communication is a technique that can be employed to meet the increased throughput ne... more Cooperative communication is a technique that can be employed to meet the increased throughput needs of next-generation WiMAX systems. In a cooperative scenario, multiple stations can jointly emulate the antenna elements of a multi-input multi-output (MIMO) system in a distributed fashion. Although distributed space-time coding (DSTC) is being considered by the IEEE 802.16j/16 m standards for spatial diversity gain, it has several inherent drawbacks. These are addressed in the recently invented randomized distributed space-time coding, called R-DSTC. In this paper, we present the framework for the R-DSTC technique in the emerging relay-assisted WiMAX network, and develop a cooperative medium access control (MAC) layer protocol, called CoopMAX, for R-DSTC deployment in an IEEE 802.16 system. Our scheme couples the MAC layer with the physical (PHY) layer for performance optimization. The PHY layer yields significant diversity gain, while the MAC layer achieves a substantial end-to-end throughput gain. Through extensive simulations, we evaluate the performance of CoopMAX and show that it can generate capacity gains of up to about 77% for an IEEE 802.16 network.
In the next-generation WiMAX system, cooperative communication is being considered as an advanced... more In the next-generation WiMAX system, cooperative communication is being considered as an advanced technique to increase the throughput and improve the signal quality. In a cooperative scenario, multiple stations can jointly emulate the antenna elements of a multi-input multi-output (MIMO) system in a distributed fashion. Unlike conventional space-time coding (STC) mechanisms used by a IEEE 802.16e antenna array, distributed space-time coding (DSTC) is employed across the cooperating stations to achieve a higher spatial diversity gain. In this paper, we present the framework for DSTC in the emerging relay-assisted WiMAX network, and develop a cooperative MAC layer protocol, called CoopMAX, for DSTC deployment in a WiMAX system. Through extensive simulations, we evaluate the performance of CoopMAX and show that DSTC can yield capacity gains of up to about 50% for the uplink of an IEEE 802.16 network.
The IEEE 802.16j protocol for a multi-hop relay (MMR) WiMAX network is being developed to increas... more The IEEE 802.16j protocol for a multi-hop relay (MMR) WiMAX network is being developed to increase data rates and extend service coverage as an enhancement of existing WiMAX standards. The IEEE 802.16j protocol supports transparent and non-transparent modes. In the transparent mode, only data traffic is relayed by an intermediate relay station (RS) between a mobile station (MS) and the base station (BS), while in the non-transparent mode, both signaling and data traffic are forwarded by RSs. Furthermore, non-transparent mode is either distributed or centralized with regard to scheduling. The difference between them resides in that distributed scheduling enables RSs to participate in bandwidth allocation (BWAlloc), while centralized scheduling leaves all BWAlloc coordinated by the BS. In this paper, we propose a novel multi-hop polling service (mPS) for non-transparent centralized scheduling in a multihop 802.16j environment. Our model is adaptive to the traffic pattern so as to provide bandwidth efficiency over access and relay links. Besides, aggregation of bandwidth requests (BWReq) from MSs is conducted at the RS to further save bandwidth. The performances of mPS with BWReq aggregation is evaluated via simulations which demonstrate our approach outperforms the current multi-hop bandwidth request mechanism in terms of overall spectrum efficiency.
IEEE Transactions on Vehicular Technology, 2013
Eurasip Journal on Wireless Communications and Networking, 2006
This paper addresses cross-layer quality-of-service (QoS) provisioning in the uplink of CDMA cell... more This paper addresses cross-layer quality-of-service (QoS) provisioning in the uplink of CDMA cellular mobile networks. Each mobile can take up to four UMTS traffic classes in our model. At the data link layer and the network layer, the QoS performances are defined in terms of signal-to-interference-plus-noise ratio and outage probability, and packet loss rate and delay, respectively. A call admission control scheme which fulfills these QoS metrics is developed to maximize the system capacity. The novelty of this paper is that the effect of the lengthening of the on-periods of non-real-time traffic classes is investigated by using the Go-Back-N automatic retransmission request mechanism with finite buffer size and limited number of retransmissions in the event of transmission errors. Simulation results for a specific example demonstrate the reasonableness of the analytical formulation. and ultra-wideband wireless mobile multimedia networks. His areas of research are in the medium access control, resource allocation with quality-of-service constraints, traffic policing with heterogeneous traffic, and cross-layer design. He is a Senior Member of the IEEE. He was on the Technical Program Committee of the IEEE WCNC
European Journal of Operational Research, 2008
... At the connection level, we present approximate analytical formulations of virtual partitioni... more ... At the connection level, we present approximate analytical formulations of virtual partitioning (VP) resource ... Finally, with cross-layer optimization, system utilization is maximized subjecting to the QoS ... 1 between the WCDMA wireless network and the wireline DiffServ network. ...
In this paper, we address the data link layer quality of service (QoS) issue by investigating the... more In this paper, we address the data link layer quality of service (QoS) issue by investigating the outage probabilities for multi-connection multiclass services in the uplink of a wideband CDMA cellular mobile network. Four Universal Mobile Telecommunications System (UMTS) QoS classes are served within each mobile user simultaneously. Each class has different QoS constraints. Assuming perfect power control, a power allocation scheme is designed to fulfill the desired received powers for all traffic classes. The outage probability is formulated for each mobile user with its traffic classes in terms of bit error rate (BER) and signal-to-interference-plus-noise ratio (SINR). In addition, an admission region, satisfying the outage probability requirements of all mobile users, is computed.
WiMAX technology, based on IEEE 802.16 standard, is a promising broadband wireless technology for... more WiMAX technology, based on IEEE 802.16 standard, is a promising broadband wireless technology for future 4G network. WiMAX provides radio access with centralized control, where bandwidth resources are managed and allocated by base station (BS) for both uplink (UL) and downlink (DL). Current WiMAX standard defines several bandwidth request (BWReq) mechanisms to serve a variety of applications, which however may not be efficient for on-off bursty traffic patterns. In this paper, we propose a novel adaptive polling service (aPS), with the advantage of significantly reducing the signaling overhead associated with the bandwidth request process without compromising the delay performance of real-time applications. Extensive simulations demonstrate that aPS outperforms existing scheduling services in terms of overall efficiency for a wide range of applications.
This contribution proposes cooperative MIMO with randomized distributed space-time coding (R-DSTC... more This contribution proposes cooperative MIMO with randomized distributed space-time coding (R-DSTC) for the 802.16m system description document (SDD).
IEEE Transactions on Wireless Communications, 2012
Relay-assisted cooperative wireless communication has been shown to have significant performance ... more Relay-assisted cooperative wireless communication has been shown to have significant performance gains over the legacy direct transmission scheme. Compared with single relay based cooperation schemes, utilizing multiple relays further improves the reliability and rate of transmissions. Distributed space-time coding (DSTC), as one of the schemes to utilize multiple relays, requires tight coordination between relays and does not perform well in a distributed environment with mobility. In this paper, a cooperative medium access control (MAC) layer protocol, called STiCMAC, is designed to allow multiple relays to transmit at the same time in an IEEE 802.11 network.
Computing Research Repository, 2011
Relay-assisted cooperative wireless communication has been shown to have significant performance ... more Relay-assisted cooperative wireless communication has been shown to have significant performance gains over the legacy direct transmission scheme. Compared with single relay based cooperation schemes, utilizing multiple relays further improves the reliability and rate of transmissions. Distributed space-time coding (DSTC), as one of the schemes to utilize multiple relays, requires tight coordination between relays and does not perform well in a distributed environment with mobility. In this paper, a cooperative medium access control (MAC) layer protocol, called \emph{STiCMAC}, is designed to allow multiple relays to transmit at the same time in an IEEE 802.11 network. The transmission is based on a novel DSTC scheme called \emph{randomized distributed space-time coding} (\emph{R-DSTC}), which requires minimum coordination. Unlike conventional cooperation schemes that pick nodes with good links, \emph{STiCMAC} picks a \emph{transmission mode} that could most improve the end-to-end data rate. Any station that correctly receives from the source can act as a relay and participate in forwarding. The MAC protocol is implemented in a fully decentralized manner and is able to opportunistically recruit relays on the fly, thus making it \emph{robust} to channel variations and user mobility. Simulation results show that the network capacity and delay performance are greatly improved, especially in a mobile environment.
A key technology in cooperative communications is distributed space-time coding (DSTC) which achi... more A key technology in cooperative communications is distributed space-time coding (DSTC) which achieves spatial diversity gain from multiple relays. A novel DSTC, called randomized distributed space-time coding (R-DSTC), shows considerable advantages over a regular DSTC in terms of system complexity. In this paper, we exploit the benefits of R-DSTC physical (PHY) layer and develop a distributed and opportunistic medium access control (MAC) layer protocol for R-DSTC deployment in an IEEE 802.11 wireless local area network (WLAN). Unlike other cooperative MAC designs, in our proposed PHY-MAC cross-layer framework, there is no need to decide which stations will serve as relays before each packet transmission. Instead, the MAC layer opportunistically recruits relay stations on the fly; any station that receives a packet from the source correctly forwards it to the destination. Through extensive simulations, we validate the efficiency of our MAC layer protocol and demonstrate that network capacity and delay performance is considerably improved with respect to legacy IEEE 802.11g network.
In next generation broadband wireless networks, the orthogonal frequency division multiple access... more In next generation broadband wireless networks, the orthogonal frequency division multiple access (OFDMA) technique provides a flexible physical interface for mobile users (MS) to share the radio resources. Since OFDMA allows MSs in different cells to reuse the same frequency subchannels to increase network spectrum utilization, MSs at the edge of a cell suffer from severe inter-cell interference from co-channel MSs in the neighboring cells. In WiMAX and LTE networks, fractional frequency reuse (FFR) is employed to mitigate the interference for edge users, but may incur a cost in terms of a lower overall spectrum utilization. In this paper, we propose a novel frequency planning scheme to improve the signal-to-interference (SIR) ratio of edge MSs in a multi-cell OFDMA system. A cell is partitioned in a way that minimizes the interference to the edge areas while sustaining a full frequency reuse factor (FRF) for each cell. Simulation results show that our scheme substantially outperforms FFR methods in terms of SIR under the condition of full frequency reuse and high traffic load.
The IEEE 802.16/WiMAX standard has fully embraced multi-antenna technology and can, thus, deliver... more The IEEE 802.16/WiMAX standard has fully embraced multi-antenna technology and can, thus, deliver robust and high transmission rates and higher system capacity. Nevertheless, due to its inherent form-factor constraints and cost concerns, a WiMAX mobile station (MS) should preferably contain fewer radio frequency (RF) chains than antenna elements. This is because RF chains are often substantially more expensive than antenna elements. Thus, antenna selection, wherein a subset of antennas is dynamically selected to connect to the limited RF chains for transceiving, is a highly appealing performance enhancement technique for multi-antenna WiMAX terminals. In this paper, a novel antenna selection protocol tailored for next-generation IEEE 802.16 mobile stations is proposed. As demonstrated by the extensive OPNET simulations, the proposed protocol delivers a significant performance improvement over conventional 802.16 terminals that lack the antenna selection capability. Moreover, the new protocol leverages the existing signaling methods defined in 802.16, thereby incurring a negligible signaling overhead and requiring only diminutive modifications of the standard. To the best of our knowledge, this paper represents the first effort to support antenna selection capability in IEEE 802.16 mobile stations.
Cooperative communication is a technique that can be employed to meet the increased throughput ne... more Cooperative communication is a technique that can be employed to meet the increased throughput needs of next-generation WiMAX systems. In a cooperative scenario, multiple stations can jointly emulate the antenna elements of a multi-input multi-output (MIMO) system in a distributed fashion. Although distributed space-time coding (DSTC) is being considered by the IEEE 802.16j/16 m standards for spatial diversity gain, it has several inherent drawbacks. These are addressed in the recently invented randomized distributed space-time coding, called R-DSTC. In this paper, we present the framework for the R-DSTC technique in the emerging relay-assisted WiMAX network, and develop a cooperative medium access control (MAC) layer protocol, called CoopMAX, for R-DSTC deployment in an IEEE 802.16 system. Our scheme couples the MAC layer with the physical (PHY) layer for performance optimization. The PHY layer yields significant diversity gain, while the MAC layer achieves a substantial end-to-end throughput gain. Through extensive simulations, we evaluate the performance of CoopMAX and show that it can generate capacity gains of up to about 77% for an IEEE 802.16 network.
In the next-generation WiMAX system, cooperative communication is being considered as an advanced... more In the next-generation WiMAX system, cooperative communication is being considered as an advanced technique to increase the throughput and improve the signal quality. In a cooperative scenario, multiple stations can jointly emulate the antenna elements of a multi-input multi-output (MIMO) system in a distributed fashion. Unlike conventional space-time coding (STC) mechanisms used by a IEEE 802.16e antenna array, distributed space-time coding (DSTC) is employed across the cooperating stations to achieve a higher spatial diversity gain. In this paper, we present the framework for DSTC in the emerging relay-assisted WiMAX network, and develop a cooperative MAC layer protocol, called CoopMAX, for DSTC deployment in a WiMAX system. Through extensive simulations, we evaluate the performance of CoopMAX and show that DSTC can yield capacity gains of up to about 50% for the uplink of an IEEE 802.16 network.
The IEEE 802.16j protocol for a multi-hop relay (MMR) WiMAX network is being developed to increas... more The IEEE 802.16j protocol for a multi-hop relay (MMR) WiMAX network is being developed to increase data rates and extend service coverage as an enhancement of existing WiMAX standards. The IEEE 802.16j protocol supports transparent and non-transparent modes. In the transparent mode, only data traffic is relayed by an intermediate relay station (RS) between a mobile station (MS) and the base station (BS), while in the non-transparent mode, both signaling and data traffic are forwarded by RSs. Furthermore, non-transparent mode is either distributed or centralized with regard to scheduling. The difference between them resides in that distributed scheduling enables RSs to participate in bandwidth allocation (BWAlloc), while centralized scheduling leaves all BWAlloc coordinated by the BS. In this paper, we propose a novel multi-hop polling service (mPS) for non-transparent centralized scheduling in a multihop 802.16j environment. Our model is adaptive to the traffic pattern so as to provide bandwidth efficiency over access and relay links. Besides, aggregation of bandwidth requests (BWReq) from MSs is conducted at the RS to further save bandwidth. The performances of mPS with BWReq aggregation is evaluated via simulations which demonstrate our approach outperforms the current multi-hop bandwidth request mechanism in terms of overall spectrum efficiency.