The Experts below are selected from a list of 7647 Experts worldwide ranked by ideXlab platform

Marco Di Renzo - One of the best experts on this subject based on the ideXlab platform.

  • Power Beacon-Assisted Millimeter Wave Ad Hoc Networks
    IEEE Transactions on Communications, 2018
    Co-Authors: Xiaohui Zhou, Salman Durrani, Jing Guo, Marco Di Renzo
    Abstract:

    Deployment of low cost Power beacons (PBs) is a promising solution for dedicated wireless Power transfer (WPT) in future wireless networks. In this paper, we present a tractable model for PB-assisted millimeter wave (mmWave) wireless ad hoc networks, where each Transmitter (TX) harvests energy from all PBs and then uses the harvested energy to Transmit information to its desired receiver. Our model accounts for realistic aspects of WPT and mmWave transmissions, such as Power circuit activation threshold, allowed Maximum harvested Power, Maximum Transmit Power, beamforming and blockage. Using stochastic geometry, we obtain the Laplace transform of the aggregate received Power at the TX to calculate the Power coverage probability. We approximate and discretize the Transmit Power of each TX into a finite number of discrete Power levels in log scale to compute the channel and total coverage probability. We compare our analytical predictions to simulations and observe good accuracy. The proposed model allows insights into effect of system parameters, such as Transmit Power of PBs, PB density, main lobe beam-width and Power circuit activation threshold on the overall coverage probability. The results confirm that it is feasible and safe to Power TXs in a mmWave ad hoc network using PBs.

  • Modeling and Analysis of Wireless Power Transfer in Heterogeneous Cellular Networks
    IEEE Transactions on Communications, 2016
    Co-Authors: Yansha Deng, Marco Di Renzo, Maged Elkashlan, Lifeng Wang, Jinhong Yuan
    Abstract:

    In this paper, we model and analyze the downlink (DL) wireless Power transfer and uplink (UL) information transmission of K-tier heterogeneous cellular networks (HCNs) with randomly located base stations (BSs) and mobile terminals (MTs). In the DL and UL, each energy-constrained MT pairs up with its corresponding BS, which provides the Maximum received Power at the MT. Due to the densely located BSs and universal frequency reuse between all tiers in HCNs, the typical MT is allowed to harvest energy from the serving BS by direct beamforming as well as from the other interfering BSs. Equipped with large storage battery, the typical MT utilizes the harvested energy to provide constant Transmit Power for the UL information transmission. Stochastic geometry is used to model and evaluate the intrinsic relationship between the energy harvested from the BSs in the DL and the information transmission performance in the UL. To well evaluate the system performance, we first derive exact expressions for the Maximum Transmit Power at MT, the UL outage probability, and the UL average ergodic rate per MT. As the number of BS antennas goes to infinity, we further derive asymptotic expressions for the Maximum Transmit Power at MT, the UL outage probability, and the UL average ergodic rate per MT. Our results show that the UL outage probability per MT first decreases and then increases with increasing the time allocation factor (the fraction of time allocated to the DL), and the UL outage probability, and the UL average ergodic rate per MT, can be largely improved by using the massive antenna arrays at the BSs.

  • Stochastic Geometry Modeling and System-Level Analysis of Uplink Heterogeneous Cellular Networks With Multi-Antenna Base Stations
    IEEE Transactions on Communications, 2016
    Co-Authors: Marco Di Renzo, Peng Guan
    Abstract:

    In this paper, mathematical frameworks for system-level analysis and design of uplink heterogeneous cellular networks with multiple antennas at the base station (BS) are introduced. Maximum ratio combining (MRC) and optimum combining (OC) at the BSs are studied and compared. A generalized cell association criterion and fractional Power control scheme are considered. The locations of all tiers of BSs are modeled as points of homogeneous and independent Poisson point processes. With the aid of stochastic geometry, coverage probability and average rate are formulated in integral but mathematically and computationally tractable expressions. Based on them, performance trends for small- and large-scale multiple-antenna BSs are discussed. Coverage and rate are shown to highly depend on several parameters, including the path-loss exponent, the fractional Power control compensation factor, and the Maximum Transmit Power of the mobile terminals. The gain of OC compared with MRC is proved to increase, if a more aggressive Power control is used and if the number of BS antennas increases but is finite. For the same number of BS antennas, OC is shown to reach the noise-limited asymptote faster than MRC. All findings are validated via Monte Carlo simulations.

  • Stochastic geometry analysis and optimization of uplink cellular networks with fractional Power control and optimum combining
    2016 IEEE International Conference on Communications ICC 2016, 2016
    Co-Authors: Peng Guan, Marco Di Renzo
    Abstract:

    A mathematical framework for system-level analysis and optimization of uplink cellular networks that use optimum combining at the Base Stations (BSs) is introduced. Fractional Power control is explicitly taken into account. The locations of the BSs are modeled as points of a homogeneous Poisson point process. With the aid of stochastic geometry, coverage and rate are formulated in integral but mathematically tractable expressions. Based on them, performance trends for small-and large-scale multi-antenna BSs are discussed. Coverage and rate are shown to be highly dependent on several parameters, including the path-loss exponent, the fractional Power control compensation factor and the Maximum Transmit Power of the mobile terminals. Based on the proposed frameworks, a heuristic algorithm for system-level optimization is proposed and its effectiveness is demonstrated with the aid of Monte Carlo simulations.

  • K-tier heterogeneous cellular networks with wireless Power transfer
    2016 IEEE International Conference on Communications ICC 2016, 2016
    Co-Authors: Yansha Deng, Marco Di Renzo, Maged Elkashlan, Lifeng Wang, Jinhong Yuan
    Abstract:

    In this paper, we model and analyze the downlink (DL) wireless Power transfer and uplink (UL) information transmission of K-tier heterogeneous cellular networks (HCNs). Due to the densely located BSs and universal frequency reuse between all tiers in HCNs, the typical mobile terminal (MT) is allowed to harvest energy from the serving BS by direct beamforming, as well as from the other interfering BSs. Equipped with large storage battery, the typical MT utilizes the harvested energy to provide constant Transmit Power for the UL information transmission. Stochastic geometry is used to model and evaluate the intrinsic relationship between the energy harvested from the BSs in the DL and the information transmission performance in the UL. To well evaluate the system performance, we derive exact expressions for the Maximum Transmit Power at MT and the UL average ergodic rate. Our results show that the UL average ergodic rate per random MT is not significantly improved by increasing the energy conversion efficiency.

Khuong Ho-van - One of the best experts on this subject based on the ideXlab platform.

  • Security Analysis for Underlay Cognitive Network with Energy-Scavenging Capable Relay over Nakagami-m Fading Channels
    Wireless Communications and Mobile Computing, 2019
    Co-Authors: Khuong Ho-van, Thiem Do-dac
    Abstract:

    This study suggests an energy-scavenging capable unlicensed relay not only to retain communications between an unlicensed sender-recipient pair in underlay cognitive networks but also to secure these communications against eavesdropping of malicious users. Message-securing capability of such a network configuration is assessed through secrecy outage probability (SOP). For this purpose, a precise closed-form formula of the SOP accounting for interference Power restriction, Nakagami-m fading, and Maximum Transmit Power restriction is first proposed. Then, the proposed formula is validated by computer simulations. Ultimately, various results are supplied to contrive that the relay position, the time percentage, and the Power percentage of the energy-scavenging technique should be appropriately chosen for achieving the best security performance. Moreover, the SOP decreases with lower severity fading level and is constant in the range of high Maximum interference Power or high Maximum Transmit Power.

  • Energy harvesting cognitive radio networks: security analysis for Nakagami-m fading
    Wireless Networks, 2019
    Co-Authors: Thiem Do-dac, Khuong Ho-van
    Abstract:

    Energy harvesting has lately been of particular attention to researchers. In addition, cognitive radio networks (CRNs) are recognized as an attainable measure for the problem of radio spectrum shortage in next generation radio access. A combination of these two technologies, which forms energy harvesting CRNs (EHCRNs), allows wireless communication terminals to prolong their operation time in limited spectrum scenarios. Nonetheless, that CRNs create opportunities for secondary users to access primary users’ spectrum induces vulnerability of message security. So far, security capability analysis of EHCRNs has been limited to Rayleigh fading whilst Nakagami- m fading is more common than Rayleigh fading and better reflects distinct fading severity degrees in practical scenarios. Accordingly, this paper firstly offers the precise security capability analysis of EHCRNs under interference Power constraint, Nakagami- m fading, Maximum Transmit Power constraint, and primary interference. Then, the offered analysis is ratified by computer simulations. Ultimately, multiple results reveal that the security capability is considerably improved with smaller primary interference and lower required security threshold. Moreover, the security capability is significantly impacted by channel severity and is optimized with appropriate selection of time percentage.

  • Relaying Communications in Energy Scavenging Cognitive Networks: Secrecy Outage Probability Analysis
    Wireless Communications and Mobile Computing, 2019
    Co-Authors: Khuong Ho-van, Thiem Do-dac
    Abstract:

    This paper exploits a self-Powered secondary relay to not only maintain but also secure communications between a secondary source and a secondary destination in cognitive radio networks when source-destination channel is unavailable. The relay scavenges energy from radio frequency (RF) signals of the primary Transmitter and the secondary source and consumes the scavenged energy for its relaying activity. Under the Maximum Transmit Power constraint, Rayleigh fading, the primary outage constraint, and the interference from the primary Transmitter, this paper suggests an accurate closed-form expression of the secrecy outage probability to promptly assess the security performance of relaying communications in energy scavenging cognitive networks. The validity of the proposed expression is verified by computer simulations. Numerous results demonstrate the security performance saturation in the range of large Maximum Transmit Power or high required outage probability of primary users. Moreover, the security performance is a function of several system parameters among which the relay’s position, the Power splitting factor, and the time splitting factor can be optimized to achieve the minimum secrecy outage probability.

  • Performance analysis of jamming technique in energy harvesting cognitive radio networks
    Telecommunication Systems, 2019
    Co-Authors: Khuong Ho-van, Thiem Do-dac
    Abstract:

    This paper proposes a jamming technique which employs a self-Powered secondary jammer to interfere a wire-tapper, who eavesdrops communications between a self-Powered secondary source and a secondary destination in energy harvesting cognitive radio networks (EHCRNs). For generality, interference from a primary source, Maximum Transmit Power constraint and interference Power constraint are considered in analyzing security performance of the proposed jamming technique in terms of security-reliability compromise. Towards this end, exact expressions of detection/eavesdropping outage probabilities at the destination/the wire-tapper are first proposed and then verified by computer simulations. Finally, results are provided to demonstrate the efficacy of the jamming technique and the key effects (interference from the primary user, Power constraints, interference Power distribution factor, and time splitting factor) on security performance of EHCRNs.

  • Effect of Nakagami-m Fading on Secrecy Outage of Energy Scavenging Underlay Cognitive Networks
    2019 International Conference on Advanced Technologies for Communications (ATC), 2019
    Co-Authors: Ngoc Pham-thi-dan, Khuong Ho-van, Thiem Do-dac, Son Vo-que, Son Pham-ngoc
    Abstract:

    The current paper proposes the exact analysis on the secrecy outage probability of energy scavenging cognitive radio networks over Nakagami-m fading channels and under both (interference and Maximum Transmit) Power constraints and primary interference. The suggested analysis is verified by Monte-Carlo simulations. Multiple results demonstrate that primary interference, required security degree, and fading severity drastically impact the security performance. Moreover, this performance can be minimized by cleverly selecting time fraction.

Akihiko Nishio - One of the best experts on this subject based on the ideXlab platform.

  • CDMA International Conference - Capacity and coverage of TD-SCDMA system with smart antenna
    Mobile Communications, 2003
    Co-Authors: Shuangfeng Han, Youzheng Wang, Jing Wang, Osamu Kato, Akihiko Nishio
    Abstract:

    In this paper, performance of smart antenna in multipath macrocell environment is studied. The system capacity and coverage of TD-SCDMA systems in the macrocell environment are studied and simulated without/with base station smart antenna which is used for dynamic channel allocation, beam forming and Power control. System capacity and coverage of TD-SCDMA systems are found to be enlarged greatly by smart antenna. There exist many tradeoff issues that deserve careful planning between cell coverage, capacity, mobile user's Maximum Transmit Power and number of smart antenna elements. For areas with different mobile user density, smart antennas with different elements are to be implemented to reduce costs.

  • Capacity and coverage of TD-SCDMA system with smart antenna
    Lecture Notes in Computer Science, 2003
    Co-Authors: Shuangfeng Han, Youzheng Wang, Jing Wang, Osamu Kato, Akihiko Nishio
    Abstract:

    In this paper, performance of smart antenna in multipath macrocell environment is studied. The system capacity and coverage of TD-SCDMA systems in the macrocell environment are studied and simulated without/with base station smart antenna which is used for dynamic channel allocation, beam forming and Power control. System capacity and coverage of TD-SCDMA systems are found to be enlarged greatly by smart antenna. There exist many tradeoff issues that deserve careful planning between cell coverage, capacity, mobile user's Maximum Transmit Power and number of smart antenna elements. For areas with different mobile user density, smart antennas with different elements are to be implemented to reduce costs.

Xiangyun Zhou - One of the best experts on this subject based on the ideXlab platform.

  • GLOBECOM Workshops - One-Way URLLC with Truncated Channel Inversion Power Control
    2019 IEEE Globecom Workshops (GC Wkshps), 2019
    Co-Authors: Shihao Yan, Xiangyun Zhou, Nan Yang, Riqing Chen
    Abstract:

    In this work, we consider one-way ultra-reliable and low-latency communication (URLLC), where only the transmission in one direction requires URLLC and the transmission in the opposite direction does not. In order to meet the low-latency requirement of the one-way URLLC, we propose to use a truncated channel inversion Power control (CIPC) to eliminate the requirement and the associated overhead of the training-based channel estimation at the receiver, while utilizing the multi-antenna technique at the Transmitter to enhance the communication reliability. We first derive the transmission outage probability achieved by the truncated CIPC by considering the impact of a finite blocklength and a Maximum Transmit Power constraint. Then, we determine the optimal constant Power of the received signals in the truncated CIPC, which minimizes the transmission outage probability. Our examination shows that the proposed truncated CIPC is an effective means to achieve the one-way URLLC, where the tradeoff among reliability, latency, and required resources (e.g., the required number of Transmit antennas, or the required Maximum Transmit Power) is revealed.

  • Covert Communication in Wireless Relay Networks
    arXiv: Information Theory, 2017
    Co-Authors: Shihao Yan, Xiangyun Zhou, Feng Shu, Jiangzhou Wang
    Abstract:

    Covert communication aims to shield the very existence of wireless transmissions in order to guarantee a strong security in wireless networks. In this work, for the first time we examine the possibility and achievable performance of covert communication in one-way relay networks. Specifically, the relay opportunistically Transmits its own information to the destination covertly on top of forwarding the source's message, while the source tries to detect this covert transmission to discover the illegitimate usage of the recourse (e.g., Power, spectrum) allocated only for the purpose of forwarding source's information. The necessary condition that the relay can Transmit covertly without being detected is identified and the source's detection limit is derived in terms of the false alarm and miss detection rates. Our analysis indicates that boosting the forwarding ability of the relay (e.g., increasing its Maximum Transmit Power) also increases its capacity to perform the covert communication in terms of achieving a higher effective covert rate subject to some specific requirement on the source's detection performance.

  • GLOBECOM - Covert Communication in Wireless Relay Networks
    GLOBECOM 2017 - 2017 IEEE Global Communications Conference, 2017
    Co-Authors: Shihao Yan, Xiangyun Zhou, Feng Shu, Jiangzhou Wang
    Abstract:

    Covert communication aims to shield the very existence of wireless transmissions in order to guarantee a strong security in wireless networks. In this work, for the first time we examine the possibility and achievable performance of covert communication in one- way relay networks. Specifically, the relay opportunistically Transmits its own information to the destination covertly on top of forwarding the source's message, while the source tries to detect this covert transmission to discover the illegitimate usage of the recourse (e.g., Power, spectrum) allocated only for the purpose of forwarding source's information. The necessary condition that the relay can Transmit covertly without being detected is identified and the source's detection limit is derived in terms of the false alarm and miss detection rates. Our analysis indicates that boosting the forwarding ability of the relay (e.g., increasing its Maximum Transmit Power) also increases its capacity to perform the covert communication in terms of achieving a higher effective covert rate subject to some specific requirement on the source's detection performance.

  • outage probability of ad hoc networks with wireless information and Power transfer
    IEEE Wireless Communications Letters, 2015
    Co-Authors: Jing Guo, Salman Durrani, Xiangyun Zhou, Halim Yanikomeroglu
    Abstract:

    This letter considers simultaneous wireless information and Power transfer in ad hoc networks, where each Transmitter (TX) is wirelessly Powered by Power beacons (PBs) and uses the aggregate received Power from PBs to Transmit to its desired receiver (RX). Using stochastic geometry, we formulate the total outage probability at a typical RX in terms of the Power and channel outage probability. The former incorporates a Power receiver activation threshold at TX while the latter incorporates Maximum Transmit Power at TX and interference at RX. For the special case of path-loss exponent of 4, we derive accurate expressions for the Power, channel and total outage probability and study the effect of the system parameters on the outage performance.

Jinhong Yuan - One of the best experts on this subject based on the ideXlab platform.

  • Modeling and Analysis of Wireless Power Transfer in Heterogeneous Cellular Networks
    IEEE Transactions on Communications, 2016
    Co-Authors: Yansha Deng, Marco Di Renzo, Maged Elkashlan, Lifeng Wang, Jinhong Yuan
    Abstract:

    In this paper, we model and analyze the downlink (DL) wireless Power transfer and uplink (UL) information transmission of K-tier heterogeneous cellular networks (HCNs) with randomly located base stations (BSs) and mobile terminals (MTs). In the DL and UL, each energy-constrained MT pairs up with its corresponding BS, which provides the Maximum received Power at the MT. Due to the densely located BSs and universal frequency reuse between all tiers in HCNs, the typical MT is allowed to harvest energy from the serving BS by direct beamforming as well as from the other interfering BSs. Equipped with large storage battery, the typical MT utilizes the harvested energy to provide constant Transmit Power for the UL information transmission. Stochastic geometry is used to model and evaluate the intrinsic relationship between the energy harvested from the BSs in the DL and the information transmission performance in the UL. To well evaluate the system performance, we first derive exact expressions for the Maximum Transmit Power at MT, the UL outage probability, and the UL average ergodic rate per MT. As the number of BS antennas goes to infinity, we further derive asymptotic expressions for the Maximum Transmit Power at MT, the UL outage probability, and the UL average ergodic rate per MT. Our results show that the UL outage probability per MT first decreases and then increases with increasing the time allocation factor (the fraction of time allocated to the DL), and the UL outage probability, and the UL average ergodic rate per MT, can be largely improved by using the massive antenna arrays at the BSs.

  • K-tier heterogeneous cellular networks with wireless Power transfer
    2016 IEEE International Conference on Communications ICC 2016, 2016
    Co-Authors: Yansha Deng, Marco Di Renzo, Maged Elkashlan, Lifeng Wang, Jinhong Yuan
    Abstract:

    In this paper, we model and analyze the downlink (DL) wireless Power transfer and uplink (UL) information transmission of K-tier heterogeneous cellular networks (HCNs). Due to the densely located BSs and universal frequency reuse between all tiers in HCNs, the typical mobile terminal (MT) is allowed to harvest energy from the serving BS by direct beamforming, as well as from the other interfering BSs. Equipped with large storage battery, the typical MT utilizes the harvested energy to provide constant Transmit Power for the UL information transmission. Stochastic geometry is used to model and evaluate the intrinsic relationship between the energy harvested from the BSs in the DL and the information transmission performance in the UL. To well evaluate the system performance, we derive exact expressions for the Maximum Transmit Power at MT and the UL average ergodic rate. Our results show that the UL average ergodic rate per random MT is not significantly improved by increasing the energy conversion efficiency.