The new generation of communication systems is moving towards using a millimeter-wave spectrum.Since the shadowing effects are undeniable in this type of propagation,the proposed Generalized Fisher(GF)distribution can...The new generation of communication systems is moving towards using a millimeter-wave spectrum.Since the shadowing effects are undeniable in this type of propagation,the proposed Generalized Fisher(GF)distribution can be useful in modeling shadowed fading channels,considering the non-linearity and the multi-cluster nature of the diffusion medium.After introducing the model,its main statistics,including Probability Density Function(PDF),Cumulative Distribution Function(CDF),Moment Generating Function(MGF),and the distribution of the sum of an arbitrary number of independent and non-identically distributed(i.n.i.d.)random variables with GF distribution are calculated.Subsequently,some wireless communication application criteria such as ergodic and outage capacities,are computed.Finally,considering the classic Wyner's wiretap model and passive eavesdropping scenario,specific security criteria,such as the probability of non-zero secrecy capacity and secrecy outage probability,are also determined.These expressions are measured in terms of either univariate or multivariate Fox's H-function.展开更多
A new analytical expression is presented for the instantaneous power Probability Density Function （PDF） of receiver signals over composite K-u/gamma fading channels. Moreover, the exact expression of channel capacit...A new analytical expression is presented for the instantaneous power Probability Density Function （PDF） of receiver signals over composite K-u/gamma fading channels. Moreover, the exact expression of channel capacity is derived in the form of an infinite series, while an accurate approximation expression is obtained in closed form. To reveal the implications of the model parameters on capacity, we provide an expression for the case of a high-SNR environment. The relationship of the presented results with previously reported results on generalised-K and K fading channels is also discussed. Finally, numerical and simulation results are presented to prove the correctness of our derived expressions.展开更多
In this paper,the performance of a mobile wireless communication network operating over the Fisher-Snedecor J composite fading channel is analyzed.Specifically,a multi-antenna base station transmits information to a s...In this paper,the performance of a mobile wireless communication network operating over the Fisher-Snedecor J composite fading channel is analyzed.Specifically,a multi-antenna base station transmits information to a single-antenna mobile receiver,which employs the maximal-ratio transmission technique to improve the quality of the received signal.The well-known random waypoint mobility model is assumed to characterize the mobility of the receiver.Under this mobility scenario,we derive exact closed-form expressions for the probability density function,cumulative distribution function,and consequently for the Outage Probability(OP),the average Bit Error Rate(BER)for different digital modulation schemes,and the average channel capacity.To shed light into the impact of different channel parameters,simple asymptotic expressions at the high SNR regime are obtained for the OP and average BER.To validate our analytical expressions,the comprehensive Monte-Carlo simulations are conducted under various configurations and both results are in excellent agreement.展开更多
Energy efficiency(EE)of downlink distributed antenna system(DAS)with multiple receive antennas is investigated over composite Rayleigh fading channel that takes the path loss and lognormal shadow fading into account.O...Energy efficiency(EE)of downlink distributed antenna system(DAS)with multiple receive antennas is investigated over composite Rayleigh fading channel that takes the path loss and lognormal shadow fading into account.Our aim is to maximize EE which is defined as the ratio of the transmission rate to the total consumed power under the constraints of the maximum transmit power of each remote antenna.According to the definition of EE,the optimized objective function is formulated with the help of Lagrangian method.By using the Karush-KuhnTucker(KKT)conditions and numerical calculation,considering both the static and dynamic circuit power consumptions,an adaptive energy efficient power allocation(PA)scheme is derived.This scheme is different from the conventional iterative PA schemes based on EE maximization since it can provide closed-form expression of PA coefficients.Moreover,it can obtain the EE performance close to the conventional iterative scheme and exhaustive search method while reducing the computation complexity greatly.Simulation results verify the effectiveness of the proposed scheme.展开更多
In this paper, we develop and analyze an energy efficient ARQ （automatic repeat request） initialized transmit diversity protocol for cooperative communications.Medium access control （MAC） layer packet retransmissi...In this paper, we develop and analyze an energy efficient ARQ （automatic repeat request） initialized transmit diversity protocol for cooperative communications.Medium access control （MAC） layer packet retransmission limit （similar to aShortRetryLimit or aLongRetryLimit [802.11-1997]） has been used as an actuator for transmit cooperative diversity initialization.We take the channel state information （CSI） as a function of retransmission tries and the number of retransmission tries is modeled as a random variable.Relays close to the source node are chosen for the transmit cooperation.Closed form expressions are obtained for symbol error rate （SER）, outage capacity and outage probability for the proposed scheme in shadowed fading channels.This cooperative scheme achieves lower signal-to-noise ratio （SNR）, stumpy outage probability, higher bandwidth, and transmit energy efficiencies for desired average symbol error rate （ASER） than the preceding ARQ based cooperative protocols.Finally, the results of computer simulations are included to demonstrate the efficacy of the proposed scheme and to verify the accuracy of the analytical expressions.展开更多
文摘The new generation of communication systems is moving towards using a millimeter-wave spectrum.Since the shadowing effects are undeniable in this type of propagation,the proposed Generalized Fisher(GF)distribution can be useful in modeling shadowed fading channels,considering the non-linearity and the multi-cluster nature of the diffusion medium.After introducing the model,its main statistics,including Probability Density Function(PDF),Cumulative Distribution Function(CDF),Moment Generating Function(MGF),and the distribution of the sum of an arbitrary number of independent and non-identically distributed(i.n.i.d.)random variables with GF distribution are calculated.Subsequently,some wireless communication application criteria such as ergodic and outage capacities,are computed.Finally,considering the classic Wyner's wiretap model and passive eavesdropping scenario,specific security criteria,such as the probability of non-zero secrecy capacity and secrecy outage probability,are also determined.These expressions are measured in terms of either univariate or multivariate Fox's H-function.
基金supported by the National NatNatural Science Foundation of China under Grants No. 61132003,No. 61101237the Open Research Fund of National Mobile Communications Research Laboratory,Southeast University under Grant No. 2012D07
文摘A new analytical expression is presented for the instantaneous power Probability Density Function （PDF） of receiver signals over composite K-u/gamma fading channels. Moreover, the exact expression of channel capacity is derived in the form of an infinite series, while an accurate approximation expression is obtained in closed form. To reveal the implications of the model parameters on capacity, we provide an expression for the case of a high-SNR environment. The relationship of the presented results with previously reported results on generalised-K and K fading channels is also discussed. Finally, numerical and simulation results are presented to prove the correctness of our derived expressions.
文摘In this paper,the performance of a mobile wireless communication network operating over the Fisher-Snedecor J composite fading channel is analyzed.Specifically,a multi-antenna base station transmits information to a single-antenna mobile receiver,which employs the maximal-ratio transmission technique to improve the quality of the received signal.The well-known random waypoint mobility model is assumed to characterize the mobility of the receiver.Under this mobility scenario,we derive exact closed-form expressions for the probability density function,cumulative distribution function,and consequently for the Outage Probability(OP),the average Bit Error Rate(BER)for different digital modulation schemes,and the average channel capacity.To shed light into the impact of different channel parameters,simple asymptotic expressions at the high SNR regime are obtained for the OP and average BER.To validate our analytical expressions,the comprehensive Monte-Carlo simulations are conducted under various configurations and both results are in excellent agreement.
基金supported by the National Natural Science Foundation of China(Nos.61571225,61571224)the Fundamental Research Funds for the Central Universities+2 种基金the Research Founding of Graduate Innovation Center in NUAA (No.kfjj20160409)the Qing Lan Project of Jiangsu,Shenzhen Strategic Emerging Industry Development Funds(No.JSGG20150331160845693)the Six Talent Peaks Project in Jiangsu Province(No.DZXX-007)
文摘Energy efficiency(EE)of downlink distributed antenna system(DAS)with multiple receive antennas is investigated over composite Rayleigh fading channel that takes the path loss and lognormal shadow fading into account.Our aim is to maximize EE which is defined as the ratio of the transmission rate to the total consumed power under the constraints of the maximum transmit power of each remote antenna.According to the definition of EE,the optimized objective function is formulated with the help of Lagrangian method.By using the Karush-KuhnTucker(KKT)conditions and numerical calculation,considering both the static and dynamic circuit power consumptions,an adaptive energy efficient power allocation(PA)scheme is derived.This scheme is different from the conventional iterative PA schemes based on EE maximization since it can provide closed-form expression of PA coefficients.Moreover,it can obtain the EE performance close to the conventional iterative scheme and exhaustive search method while reducing the computation complexity greatly.Simulation results verify the effectiveness of the proposed scheme.
基金Supported by the National Natral Science Foundation of China (Grant No 60602058)the National High Technology Research and Development Program of China (Grant No 2006AA01Z257)
文摘In this paper, we develop and analyze an energy efficient ARQ （automatic repeat request） initialized transmit diversity protocol for cooperative communications.Medium access control （MAC） layer packet retransmission limit （similar to aShortRetryLimit or aLongRetryLimit [802.11-1997]） has been used as an actuator for transmit cooperative diversity initialization.We take the channel state information （CSI） as a function of retransmission tries and the number of retransmission tries is modeled as a random variable.Relays close to the source node are chosen for the transmit cooperation.Closed form expressions are obtained for symbol error rate （SER）, outage capacity and outage probability for the proposed scheme in shadowed fading channels.This cooperative scheme achieves lower signal-to-noise ratio （SNR）, stumpy outage probability, higher bandwidth, and transmit energy efficiencies for desired average symbol error rate （ASER） than the preceding ARQ based cooperative protocols.Finally, the results of computer simulations are included to demonstrate the efficacy of the proposed scheme and to verify the accuracy of the analytical expressions.
