The closed-form formula derivation of the power domain cooperative non-orthogonal multiple access(NOMA)system is of great significance for further improving the performance of the system.However,the system performance...The closed-form formula derivation of the power domain cooperative non-orthogonal multiple access(NOMA)system is of great significance for further improving the performance of the system.However,the system performance formulas of the channel capacity and the paired bit error rate pairwise error probability(PEP)are too complicated,which have increased the difficulty in system performance optimization.Therefore,based on the amplify forward(AF)relay cooperative NOMA model,the signal interference noise ratio(SINR)formulas of the two user nodes are constructed.Through the assumption of that,the symbol error rate(SER)of each user is fair,the simplification condition of moment generating function(MGF)with the harmonic mean form is satisfied.Combined with the SER calculation formula of MGF,the system SER asymptotically tight approximation formula with simple structure is derived at high signal-to-noise ratio(SNR).The Monte Carlo simulation results show that,the formula can accurately describe the SER performance of the power domain cooperative NOMA system with the non-ideal successive interference cancellation(SIC)system when SNR is high.Under the condition of certain total power,the optimal power allocation factor is solved in order to minimize the total system SER.展开更多
In this paper,the performance analysis of cooperative space shift keying(SSK)system with dual hop amplify and forward(AF)in receive correlated Rayleigh channel is presented.By means of the performance analysis,a close...In this paper,the performance analysis of cooperative space shift keying(SSK)system with dual hop amplify and forward(AF)in receive correlated Rayleigh channel is presented.By means of the performance analysis,a closed form approximate expression of the average bit error rate(BER)is derived for the performance evaluation.With this expression,in a high signal to noise ratio(SNR)region,a tight closed form asymptotic BER of the system is also derived.It can simplify the calculation of average BER and provide effective evaluation for asymptotic performance.By minimizing this asymptotic BER expression,a suboptimum power allocation(PA)scheme is developed,and the closed form PA coefficients are obtained.Simulation indicates that the suboptimal PA scheme outperforms the conventional equal PA scheme,and its performance is very close to that of the exhaustive search based optimal PA scheme but with low complexity.Moreover,the system performance under the spatially correlated channel is worse than that in spatially independent channel due to the effect of spatial correlation.展开更多
This paper aims to avoid the interference imposed by the secondary user on a primary user in Cognitive Radio Network (CRN). In CRN, the interference from secondary user enforced on primary user mainly depends on spect...This paper aims to avoid the interference imposed by the secondary user on a primary user in Cognitive Radio Network (CRN). In CRN, the interference from secondary user enforced on primary user mainly depends on spectral interval between primary and secondary systems. Moreover, it also depends on the power allocated to the secondary user. In order to avoid interference imposed by secondary user on primary user, a Hybrid Relaying Protocol for Joint Power and Subcarrier Allocation for Orthogonal Frequency Division Multiplexing (OFDM) based Cognitive Radio Networks is proposed. In hybrid relaying protocol, a secondary user uses amplify and forward (AF) protocol and decode and forward (DF) protocol based on the requirement to maximize network throughput. A greedy algorithm is proposed for the selection of relay to get the optimal solution. Moreover, an efficient hybrid power and subcarrier algorithm is used by considering interference constraint imposed by cognitive network to the primary user.展开更多
This paper studies the resource allocation for a multi-user two-way amplify-and-forward （AF） relay network over orthogonal frequency-division multiplexing （OFDM） technology, where all users communicate with their ...This paper studies the resource allocation for a multi-user two-way amplify-and-forward （AF） relay network over orthogonal frequency-division multiplexing （OFDM） technology, where all users communicate with their pre-assigned partners. Using convex optimization techniques, an optimal solution to minimize the total transmit power while satisfy each user-pair＇s data rate requirements is proposed. We divide the resource allocation problem into two subproblems： （1） power optimization within user-pair and relay in each subcarrier. （2） optimal subcarrier allocation and sum power assignment among N parallel OFDM subcarriers. Closed-form expressions of the power among user-pair and relay can be obtained in subproblem （1）, and so the proposed algorithm decreases the variable dimensionality of the objective function to reduce the complexity of this optimization problem. To solve it, a three-step suboptimal approach is proposed to assign the resources to user-pairs： Firstly, decompose each user-pair into two sub user-pairs which have one-way and two-way relaying transmission modes. Secondly, allocate the subcarriers to the new mode user-pairs and assign the transmit power to each carrier. Thirdly, distribute the assigned power to three nodes allocated in the subcarrier. Simulation results demonstrate the significant power is saved with the proposed solutions, as compared to a fixed subcarrier allocation.展开更多
基金the National Natural Science Foundation of China(No.62001001)。
文摘The closed-form formula derivation of the power domain cooperative non-orthogonal multiple access(NOMA)system is of great significance for further improving the performance of the system.However,the system performance formulas of the channel capacity and the paired bit error rate pairwise error probability(PEP)are too complicated,which have increased the difficulty in system performance optimization.Therefore,based on the amplify forward(AF)relay cooperative NOMA model,the signal interference noise ratio(SINR)formulas of the two user nodes are constructed.Through the assumption of that,the symbol error rate(SER)of each user is fair,the simplification condition of moment generating function(MGF)with the harmonic mean form is satisfied.Combined with the SER calculation formula of MGF,the system SER asymptotically tight approximation formula with simple structure is derived at high signal-to-noise ratio(SNR).The Monte Carlo simulation results show that,the formula can accurately describe the SER performance of the power domain cooperative NOMA system with the non-ideal successive interference cancellation(SIC)system when SNR is high.Under the condition of certain total power,the optimal power allocation factor is solved in order to minimize the total system SER.
基金supported in part by the Fundamental Research Funds for the Central Universities of NUAA (No.kfjj20180405)the Natural Science Foundation of Jiangsu in China (No. BK20181289)the Six Talent Peaks Project in Jiangsu (No.2015-DZXX-007)
文摘In this paper,the performance analysis of cooperative space shift keying(SSK)system with dual hop amplify and forward(AF)in receive correlated Rayleigh channel is presented.By means of the performance analysis,a closed form approximate expression of the average bit error rate(BER)is derived for the performance evaluation.With this expression,in a high signal to noise ratio(SNR)region,a tight closed form asymptotic BER of the system is also derived.It can simplify the calculation of average BER and provide effective evaluation for asymptotic performance.By minimizing this asymptotic BER expression,a suboptimum power allocation(PA)scheme is developed,and the closed form PA coefficients are obtained.Simulation indicates that the suboptimal PA scheme outperforms the conventional equal PA scheme,and its performance is very close to that of the exhaustive search based optimal PA scheme but with low complexity.Moreover,the system performance under the spatially correlated channel is worse than that in spatially independent channel due to the effect of spatial correlation.
文摘This paper aims to avoid the interference imposed by the secondary user on a primary user in Cognitive Radio Network (CRN). In CRN, the interference from secondary user enforced on primary user mainly depends on spectral interval between primary and secondary systems. Moreover, it also depends on the power allocated to the secondary user. In order to avoid interference imposed by secondary user on primary user, a Hybrid Relaying Protocol for Joint Power and Subcarrier Allocation for Orthogonal Frequency Division Multiplexing (OFDM) based Cognitive Radio Networks is proposed. In hybrid relaying protocol, a secondary user uses amplify and forward (AF) protocol and decode and forward (DF) protocol based on the requirement to maximize network throughput. A greedy algorithm is proposed for the selection of relay to get the optimal solution. Moreover, an efficient hybrid power and subcarrier algorithm is used by considering interference constraint imposed by cognitive network to the primary user.
基金supported by the National Natural Science Foundation of China (6035003,60572149)
文摘This paper studies the resource allocation for a multi-user two-way amplify-and-forward （AF） relay network over orthogonal frequency-division multiplexing （OFDM） technology, where all users communicate with their pre-assigned partners. Using convex optimization techniques, an optimal solution to minimize the total transmit power while satisfy each user-pair＇s data rate requirements is proposed. We divide the resource allocation problem into two subproblems： （1） power optimization within user-pair and relay in each subcarrier. （2） optimal subcarrier allocation and sum power assignment among N parallel OFDM subcarriers. Closed-form expressions of the power among user-pair and relay can be obtained in subproblem （1）, and so the proposed algorithm decreases the variable dimensionality of the objective function to reduce the complexity of this optimization problem. To solve it, a three-step suboptimal approach is proposed to assign the resources to user-pairs： Firstly, decompose each user-pair into two sub user-pairs which have one-way and two-way relaying transmission modes. Secondly, allocate the subcarriers to the new mode user-pairs and assign the transmit power to each carrier. Thirdly, distribute the assigned power to three nodes allocated in the subcarrier. Simulation results demonstrate the significant power is saved with the proposed solutions, as compared to a fixed subcarrier allocation.
