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

  • secret channel training to enhance physical layer security with a full duplex receiver
    IEEE Transactions on Information Forensics and Security, 2018
    Co-Authors: Xiangyun Zhou, Nan Yang, Thushara D Abhayapala, Lee A Swindlehurst
    Abstract:

    This paper proposes a new channel training (CT) scheme for a full-duplex receiver to enhance physical layer security. Equipped with $N_{B}$ full-duplex antennas, the receiver simultaneously receives the Information Signal and transmits artificial noise (AN). In order to reduce the non-cancellable self-interference due to the transmitted AN, the receiver has to estimate the self-interference channel prior to the data communication phase. In the proposed CT scheme, the receiver transmits a limited number of pilot symbols that are known only to itself. Such a secret CT scheme prevents an eavesdropper from estimating the jamming channel from the receiver to the eavesdropper, hence effectively degrading the eavesdropping capability. We analytically examine the connection probability (i.e., the probability of the data being successfully decoded by the receiver) of the legitimate channel and the secrecy outage probability due to eavesdropping for the proposed secret CT scheme. Based on our analysis, the optimal power allocation between CT and data/AN transmission at the legitimate transmitter/receiver is determined. Our examination shows that the newly proposed secret CT scheme significantly outperforms the non-secret CT scheme that uses publicly known pilots when the number of antennas at the eavesdropper is larger than one.

  • artificial noise aided secure multi antenna transmission with limited feedback
    IEEE Transactions on Wireless Communications, 2015
    Co-Authors: Xi Zhang, Matthew R. Mckay, Xiangyun Zhou
    Abstract:

    We present an optimized secure multi-antenna transmission approach based on artificial-noise-aided beamforming, with limited feedback from a desired single-antenna receiver. To deal with beamformer quantization errors as well as unknown eavesdropper channel characteristics, our approach is aimed at maximizing throughput under dual performance constraints—a connection outage constraint on the desired communication channel and a secrecy outage constraint to guard against eavesdropping. We propose an adaptive transmission strategy that judiciously selects the wiretap coding parameters, as well as the power allocation between the artificial noise and the Information Signal. This optimized solution reveals several important differences with respect to solutions designed previously under the assumption of perfect feedback. We also investigate the problem of how to most efficiently utilize the feedback bits. The simulation results indicate that a good design strategy is to use approximately 20% of these bits to quantize the channel gain Information, with the remainder to quantize the channel direction, and this allocation is largely insensitive to the secrecy outage constraint imposed. In addition, we find that 8 feedback bits per transmit antenna is sufficient to achieve approximately 90% of the throughput attainable with perfect feedback.

  • secure transmission with artificial noise over fading channels achievable rate and optimal power allocation
    IEEE Transactions on Vehicular Technology, 2010
    Co-Authors: Xiangyun Zhou, Matthew R. Mckay
    Abstract:

    We consider the problem of secure communication with multiantenna transmission in fading channels. The transmitter simultaneously transmits an Information-bearing Signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form expression of an achievable secrecy rate and use it as the objective function to optimize the transmit power allocation between the Information Signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple yet near-optimal strategy for the case of noncolluding eavesdroppers. When the number of colluding eavesdroppers increases, more power should be used to generate the artificial noise. We also provide an upper bound on the SNR, above which, the achievable secrecy rate is positive and shows that the bound is tight at low SNR. Furthermore, we consider the impact of imperfect channel state Information (CSI) at both the transmitter and the receiver and find that it is wise to create more artificial noise to confuse the eavesdroppers than to increase the Signal strength for the intended receiver if the CSI is not accurately obtained.

  • secure transmission with artificial noise over fading channels achievable rate and optimal power allocation
    arXiv: Information Theory, 2010
    Co-Authors: Xiangyun Zhou, Matthew R. Mckay
    Abstract:

    We consider the problem of secure communication with multi-antenna transmission in fading channels. The transmitter simultaneously transmits an Information bearing Signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form expression of an achievable secrecy rate, and use it as the objective function to optimize the transmit power allocation between the Information Signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple yet near optimal strategy for the case of non-colluding eavesdroppers. When the number of colluding eavesdroppers increases, more power should be used to generate the artificial noise. We also provide an upper bound on the Signal-to-noise ratio (SNR) above which the achievable secrecy rate is positive and show that the bound is tight at low SNR. Furthermore, we consider the impact of imperfect channel state Information (CSI) at both the transmitter and the receiver and find that it is wise to create more artificial noise to confuse the eavesdroppers than to increase the Signal strength for the intended receiver if the CSI is not accurately obtained.

  • Physical layer security with artificial noise: Secrecy capacity and optimal power allocation
    3rd International Conference on Signal Processing and Communication Systems, ICSPCS'2009 - Proceedings, 2009
    Co-Authors: Xiangyun Zhou, Matthew R. Mckay
    Abstract:

    We consider the problem of secure communication in wireless fading channels in the presence of non-colluding passive eavesdroppers. The transmitter has multiple antennas and is able to simultaneously transmit an Information bearing Signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form lower bound for secrecy capacity, which is used as the objective function to optimize transmit power allocation between the Information Signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple and generic strategy which achieves near optimal capacity performance. We also find that adaptive power allocation based on each channel realization provides no or insignificant capacity improvement over equal power allocation.

J. Sheltry - One of the best experts on this subject based on the ideXlab platform.

  • Multiple tone interference of frequency-hopped noncoherent MFSK Signals transmitted over Ricean fading channels
    IEEE Transactions on Communications, 1996
    Co-Authors: R C Robertson, J. Sheltry
    Abstract:

    This paper investigates the performance degradation resulting from multitone interference of orthogonal, frequency-hopped, noncoherent M-ary frequency-shift keyed receivers (FH/MFSK) where the effect of thermal and other wideband noise is not neglected. The multiple, equal power jamming tones are assumed to correspond to some or all of the possible FH M-ary orthogonal Signaling tones. Furthermore, the channel is modeled as a Ricean fading channel; and both the Signaling tones and the multiple interference tones are assumed to be affected by channel fading. It is also assumed that channel fading need not necessarily affect the Signaling tones and the interference tones in the same-way. When the Information Signal power exceeds the power of the individual interference tones, poorer overall system performance is obtained when the multiple interfering tones experience fading. This trend is accentuated as M increases. When the Information Signal experiences fading, the effect of fading multiple interference tones on overall system performance lessens, and for a Rayleigh-faded Information Signal, fading of the multiple interference tones has no effect on overall system performance regardless of M.

  • Multiple tone interference of frequency-hopped noncoherent MFSK Signals transmitted over Ricean fading channels
    Proceedings of MILCOM '95, 2026
    Co-Authors: R C Robertson, J. Sheltry
    Abstract:

    This paper investigates the performance degradation resulting from multitone interference of orthogonal, noncoherent frequency-hopped M-ary frequency-shift keyed receivers (FH/MFSK) where the effect of thermal and other wideband noise is not neglected. The multiple, equal power jamming tones are assumed to correspond to some or all of the possible FH M-ary orthogonal Signaling tones. Furthermore, the channel is modeled as a Ricean fading channel, a possibility precluded when thermal noise is neglected; and both the Signaling tones and the multiple interference tones are assumed to be affected by channel fading. Only band multitone interference is considered, and it is assumed that jammed hop bands contain a single interfering tone at one of the M possible Signaling frequencies. When the Information Signal is not affected by fading but the multiple interference tones are, the effect on the overall performance of the FH/MFSK system is very small when the power of the individual interference tones is greater than or equal to the Information Signal power. When the Information Signal power exceeds the power of the individual interference tones, the counterintuitive result of poorer overall system performance when the multiple interfering tones experience fading as compared with when they do not, is obtained. This trend is accentuated as M increases. When the Information Signal experiences fading, the effect of fading multiple interference tones on overall system performance lessens, and for a Rayleigh faded Information Signal, fading of the multiple interference tones has no effect on overall system performance regardless of M.

Matthew R. Mckay - One of the best experts on this subject based on the ideXlab platform.

  • artificial noise aided secure multi antenna transmission with limited feedback
    IEEE Transactions on Wireless Communications, 2015
    Co-Authors: Xi Zhang, Matthew R. Mckay, Xiangyun Zhou
    Abstract:

    We present an optimized secure multi-antenna transmission approach based on artificial-noise-aided beamforming, with limited feedback from a desired single-antenna receiver. To deal with beamformer quantization errors as well as unknown eavesdropper channel characteristics, our approach is aimed at maximizing throughput under dual performance constraints—a connection outage constraint on the desired communication channel and a secrecy outage constraint to guard against eavesdropping. We propose an adaptive transmission strategy that judiciously selects the wiretap coding parameters, as well as the power allocation between the artificial noise and the Information Signal. This optimized solution reveals several important differences with respect to solutions designed previously under the assumption of perfect feedback. We also investigate the problem of how to most efficiently utilize the feedback bits. The simulation results indicate that a good design strategy is to use approximately 20% of these bits to quantize the channel gain Information, with the remainder to quantize the channel direction, and this allocation is largely insensitive to the secrecy outage constraint imposed. In addition, we find that 8 feedback bits per transmit antenna is sufficient to achieve approximately 90% of the throughput attainable with perfect feedback.

  • secure transmission with artificial noise over fading channels achievable rate and optimal power allocation
    IEEE Transactions on Vehicular Technology, 2010
    Co-Authors: Xiangyun Zhou, Matthew R. Mckay
    Abstract:

    We consider the problem of secure communication with multiantenna transmission in fading channels. The transmitter simultaneously transmits an Information-bearing Signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form expression of an achievable secrecy rate and use it as the objective function to optimize the transmit power allocation between the Information Signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple yet near-optimal strategy for the case of noncolluding eavesdroppers. When the number of colluding eavesdroppers increases, more power should be used to generate the artificial noise. We also provide an upper bound on the SNR, above which, the achievable secrecy rate is positive and shows that the bound is tight at low SNR. Furthermore, we consider the impact of imperfect channel state Information (CSI) at both the transmitter and the receiver and find that it is wise to create more artificial noise to confuse the eavesdroppers than to increase the Signal strength for the intended receiver if the CSI is not accurately obtained.

  • secure transmission with artificial noise over fading channels achievable rate and optimal power allocation
    arXiv: Information Theory, 2010
    Co-Authors: Xiangyun Zhou, Matthew R. Mckay
    Abstract:

    We consider the problem of secure communication with multi-antenna transmission in fading channels. The transmitter simultaneously transmits an Information bearing Signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form expression of an achievable secrecy rate, and use it as the objective function to optimize the transmit power allocation between the Information Signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple yet near optimal strategy for the case of non-colluding eavesdroppers. When the number of colluding eavesdroppers increases, more power should be used to generate the artificial noise. We also provide an upper bound on the Signal-to-noise ratio (SNR) above which the achievable secrecy rate is positive and show that the bound is tight at low SNR. Furthermore, we consider the impact of imperfect channel state Information (CSI) at both the transmitter and the receiver and find that it is wise to create more artificial noise to confuse the eavesdroppers than to increase the Signal strength for the intended receiver if the CSI is not accurately obtained.

  • Physical layer security with artificial noise: Secrecy capacity and optimal power allocation
    3rd International Conference on Signal Processing and Communication Systems, ICSPCS'2009 - Proceedings, 2009
    Co-Authors: Xiangyun Zhou, Matthew R. Mckay
    Abstract:

    We consider the problem of secure communication in wireless fading channels in the presence of non-colluding passive eavesdroppers. The transmitter has multiple antennas and is able to simultaneously transmit an Information bearing Signal to the intended receiver and artificial noise to the eavesdroppers. We obtain an analytical closed-form lower bound for secrecy capacity, which is used as the objective function to optimize transmit power allocation between the Information Signal and the artificial noise. Our analytical and numerical results show that equal power allocation is a simple and generic strategy which achieves near optimal capacity performance. We also find that adaptive power allocation based on each channel realization provides no or insignificant capacity improvement over equal power allocation.

Zhiguo Ding - One of the best experts on this subject based on the ideXlab platform.

  • on secrecy outage of miso swipt systems in the presence of imperfect csi
    European Signal Processing Conference, 2016
    Co-Authors: Yansha Deng, Yunfei Chen, Zhiguo Ding
    Abstract:

    In this work, a multiple-input single-output (MISO) simultaneous wireless Information and power transfer (SWIPT) system including one base station (BS) equipped with multiple antennas, one desired single-antenna Information receiver (IR) and N (N > 1) single-antenna energy-harvesting receivers (ERs) is considered. By considering that the Information Signal of the desired IR may be eavesdropped by ERs if ERs are malicious, we investigate the secrecy performance of the target MISO SWIPT system when imperfect channel state Information (CSI) is available and adopted for transmit antenna selection at the BS. Considering that each eavesdropping link experiences independent not necessarily identically distributed Rayleigh fading, the closed-form expressions for the exact and the asymptotic secrecy outage probability are derived and verified by simulation results.

  • on secrecy performance of miso swipt systems with tas and imperfect csi
    IEEE Transactions on Communications, 2016
    Co-Authors: Yansha Deng, Yunfei Chen, Jing Yang, Zhiguo Ding
    Abstract:

    In this paper, a multiple-input single-output (MISO) simultaneous wireless Information and power transfer (SWIPT) system, including one base station (BS) equipped with multiple antennas, one desired single-antenna Information receiver (IR), and $N$ ( $N > 1$ ) single-antenna energy-harvesting receivers (ERs) is considered. Assuming that the Information Signal to the desired IR may be eavesdropped by ERs if ERs are malicious, we investigate the secrecy performance of the target MISO SWIPT system when imperfect channel state Information (CSI) is available and adopted for transmit antenna selection at the BS. Considering that each eavesdropping link experiences independent but not necessarily identically distributed Rayleigh fading, the closed-form expressions for the exact and the asymptotic secrecy outage probability, and the average secrecy capacity are derived and verified by simulations. Furthermore, the optimal power splitting factor is derived for each ER to realize the tradeoff between the energy harvesting and the Information eavesdropping. Our results reveal the impact of the imperfect CSI on the secrecy performance of MISO SWIPT systems in the presence of multiple wiretap channels.

Theodoros A Tsiftsis - One of the best experts on this subject based on the ideXlab platform.

  • on the performance of wireless powered cognitive relay network with interference alignment
    IEEE Transactions on Communications, 2018
    Co-Authors: Sultangali Arzykulov, Theodoros A Tsiftsis, Galymzhan Nauryzbayev, Mohamed Abdallah
    Abstract:

    In this paper, a two-hop decode-and-forward wireless powered relaying cognitive radio network with interference alignment over Rayleigh fading channels is investigated. The energy-constrained secondary relay node harvests energy from both the Information and interference Signals. Then, the harvested energy is used by the relay to forward the Information Signal from the source to the destination node. By applying beamforming matrices to primary and secondary networks, the performance metrics, such as outage probability, capacity, and bit error rate are studied under perfect and imperfect channel state Information scenarios for both power-splitting relaying (PSR) and time-switching relaying (TSR) protocols. In addition, the optimal network performance is achieved by calculating the optimal energy harvesting time-switching and power-splitting coefficients. Finally, closed-form expressions for the outage probability of primary and secondary users are derived. Monte Carlo simulation results corroborate the analytical ones and show that the PSR technique outperforms TSR in the considered system model.

  • wireless Information and power transfer in relay systems with multiple antennas and interference
    IEEE Transactions on Communications, 2015
    Co-Authors: Guangxu Zhu, Caijun Zhong, Himal A. Suraweera, Zhaoyang Zhang, George K Karagiannidis, Theodoros A Tsiftsis
    Abstract:

    In this paper, an energy harvesting dual-hop relaying system without/with the presence of co-channel interference (CCI) is investigated. Specifically, the energy constrained multi-antenna relay node is powered by either the Information Signal of the source or via the Signal receiving from both the source and interferer. In particular, we first study the outage probability and ergodic capacity of an interference free system, and then extend the analysis to an interfering environment. To exploit the benefit of multiple antennas, three different linear processing schemes are investigated, namely, 1) Maximum ratio combining/maximum ratio transmission (MRC/MRT), 2) Zero-forcing/MRT (ZF/MRT) and 3) Minimum mean-square error/MRT (MMSE/MRT). For all schemes, both the systems outage probability and ergodic capacity are studied, and the achievable diversity order is also presented. In addition, the optimal power splitting ratio minimizing the outage probability is characterized. Our results show that the implementation of multiple antennas increases the energy harvesting capability, hence, significantly improves the systems performance. Moreover, it is demonstrated that the CCI could be potentially exploited to substantially boost the performance, while the choice of a linear processing scheme plays a critical role in determining how much gain could be extracted from the CCI.