提出一种基于信噪比最优顺序的正交频分多(OFDMA)上行链路快速串行干扰消除(SIC)方法.该方法利用干扰矩阵的各列近似正交特性,按照它们的相关程度,得到解调后信噪比最优的串行干扰消除子载波排列,避免了伪逆矩阵的求解,具有解调后各子载波上信号的信噪比联合最优、计算量低的特点,且可应用在任何子载波分配策略中.理论分析了OFDMA上行链路中各用户存在频偏时系统性能的下降.计算机仿真结果表明,该SIC方法能减小系统误码率.
A successive interference cancellation (SIC) algorithm based on signal to noise ratio (SNR) is proposed to mitigate the interference in the upllnk orthogonal frequency division multiple access (OFDMA)systems. An optimal permutation of the detection order based on post SNR can be first found for the orthogonality of columns in interference matrix. Performance degradation in uplink OFDMA systems with CFOs is analyzed. Compared with other interference cancellation algorithms, there is no need for pseudo inverse operation. The algorithm is optimized on the means of SNR of all subcarriers in OFDMA systems and also applied in generalized carrier assignment scheme (CAS). The validity of the proposed algorithm is proved to be validated by numerical simulations