针对采用GFDM(Generalized Frequency Division Multiplex)多载波调制的移动通信系统中，非正交性引起的ICI(Inter Carrier Interference)、OOBE(Out of Band Emission)问题，以及在衰落信道条件下存在的时域、频域选择性衰落问题，提出了根据干扰信号能量预估值来调整原型滤波器参数以降低干扰的方法.在此基础上，采用结合了压缩感知的低复杂度预编码算法，在降低计算复杂度的同时能进一步提高频谱效率.使用Matlab软件搭建模型验证上述方法，仿真结果表明，采用上述降低干扰的方法可以将GFDM系统BER(Bit Error Rate)控制在较低水平.
The disturbances such as: ICI(Inter Carrier Interference), OOBE(Out of Band Emission), etc. in GFDM(Generalized Frequency Division Multiplex) multicarrier modulation communication system may degrade system performance, and timefrequency dualselective fading will worsen this issue. A channel estimation algorithm is introduced to lower the system’s interferences and computational complexity, by optimizing the prototype filter parameters according to disturb signal energy. Precode and equilibrium are also chosen to suppress ICI, OOBE, and interference from other users or antennas. A simulation model by Matlab is set up, BER curves and constellation diagrams have been worked out to evaluate the system performances. The simulation result indicates that GFDM with those corrective actions may get a lower BER level.
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