中文摘要：

物理层网络编码（PNC）因其在提高网络吞吐量、减少传输时延等方面的优越性,已成为近年的研究热点。为了弥补PNC在频率选择性衰落信道中的性能损失,将OFDM调制技术应用到物理层网络编码中,构成了OFDM-PNC系统。重点研究了OFDM-PNC中继系统的信道估计技术,使用Matlab对最小平方（LS）、最小均方误差（MMSE）及基于奇异值分解（SVD）信道估计算法的性能进行仿真,仿真结果验证了理论分析。

英文摘要：

Physical layer network coding （PNC） has became an important research topic due to its ability to improve the network throughput and reduce transmission delay.In order to make up for the performance loss of PNC in frequency selective fading channel, OFDM modulation technique is applied to the physical layer network coding, constitutes the OFDM-PNC system.This paper mainly studies the channel estimation technology of OFDM-PNC relay system, using Matlab to simulate the estimation performance of least square（LS）, minimum mean square error （MMSE） and singular value decomposition （SVD） channel estimation algorithm. The simulation results verify the theoretical analysis.