多中继协同差分宽带通信性能优化

Performance optimization of differential broadband communication with multiple relay cooperation

多中继协同的差分宽带通信方法能得到完全的协同分集和频率分集增益,为了优化误比特性能,以均值信噪比最大为准则,对影响均值信噪比的多个参数进行理论分析和优化求解。理论分析表明中继个数和中继位置是关于均值信噪比的非凸函数且优化解在边界点上。为使优化更有实际意义,确定了常用的中继个数和中继位置取值,在此基础上得到了功率分配因子和最大比合并因子的最优解。仿真实验结果验证了理论分析及参数优化解的有效性,以及多参数优化误比特性能的优越性。另外,理论分析和仿真结果还给出了合理选择中继个数和中继位置的方法。

The proposed differential broadband communication scheme with multiple relay cooperating can acquire full cooperative and frequency diversity gains.Firstly,the effect of multiple parameters on the average SNR value is analyzed,and then the optimal solution of multiple parameters based on maximized average SNR value is acquired to improve the performance of bit error ratio（BER）.Theoretical analysis demonstrates that average SNR is a non-convex function of relay number and relay location.The optimal solution of these parameters is at the boundary points in the parameter domain.In order to make parameter optimization more applicable,through selecting groups of relay number and relay location used frequently in practice,the optimal solutions of power distribution factor and maximum ratio combining factor are obtained.Simulation results demonstrate the validity of theoretical analysis and the multi-parameter optimal solution is proved,and the superiority of BER performance is also proved.We also present a reasonable method for selecting relay number and relay location.