Chitra S, Kumaratharan N
Department of Electronics and Communication Engineering, Rajalakshmi Engineering College, Chennai, Tamil Nadu, India.
Department of Information Technology, Sri Venkateswara College of Engineering, Chennai, Tamil Nadu, India.
PLoS One. 2015 Mar 19;10(3):e0116326. doi: 10.1371/journal.pone.0116326. eCollection 2015.
Multi-carrier code division multiple access (MC-CDMA) technique is one of the strong candidates for next generation wireless mobile communication systems. Multi-carrier systems are very much sensitive to carrier frequency offset (CFO) results in intercarrier interference (ICI). To mitigate ICI without any spectral loss, a second order duobinary coded phase rotated conjugate cancellation algorithm is proposed in this paper. In the conventional phase rotated conjugate cancellation (PRCC) technique, one path carries the MC-CDMA signal with a phase spin of ϕ and the other path carries the conjugate of the first path signal with -ϕ phase spin. This artificial phase rotation allows the transmitter to tune the transmitted signals so that the ICI effects could be mutually cancelled at the receiver. Although the PRCC technique reduces the spectral efficiency, the limitation can be overcome by the joint second order duobinary coding scheme with PRCC technique. In the proposed method, the correlative coding between the binary symbols modulated on adjacent subcarriers is used to reduce the ICI without any spectral loss. Simulation results show that the proposed PRCC method provides better carrier to interference ratio (CIR) and bit error rate (BER) performances compared to the conventional conjugate cancellation (CC) technique.
多载波码分多址（MC-CDMA）技术是下一代无线移动通信系统的有力候选技术之一。多载波系统对载波频率偏移（CFO）非常敏感，会导致载波间干扰（ICI）。为了在不产生任何频谱损失的情况下减轻ICI，本文提出了一种二阶双二进制编码相位旋转共轭抵消算法。在传统的相位旋转共轭抵消（PRCC）技术中，一条路径携带具有ϕ相位旋转的MC-CDMA信号，另一条路径携带具有-ϕ相位旋转的第一路径信号的共轭信号。这种人为的相位旋转允许发射机调整发射信号，以便在接收机处可以相互抵消ICI效应。虽然PRCC技术降低了频谱效率，但通过将二阶双二进制编码方案与PRCC技术相结合可以克服这一限制。在所提出的方法中，相邻子载波上调制的二进制符号之间的相关编码用于在不产生任何频谱损失的情况下降低ICI。仿真结果表明，与传统的共轭抵消（CC）技术相比，所提出的PRCC方法提供了更好的载干比（CIR）和误码率（BER）性能。
