联合子载波抑制与配对的双向DF-PLNCOFDM中继

Joint Subcarrier Suppression and Subcarrier Pairing for Two-Way OFDM Relay with DF-PLNC

子载波抑制(SS)技术已被证明能够显著提高正交频分复用(OFDM)系统的误码率性能,因此引起了学术界的广泛关注。在双向OFDM中继网络(TWRN)中,由于两个源节点与中继之间的链路具有独立性,直接应用子载波抑制技术会造成两条链路的活跃子载波具有非对称性,从而导致大量子载波在中继节点无法实现网络编码。提出了一种联合子载波抑制与子载波配对(SP)的双向译码转发(DF)-物理层网络编码(PLNC)OFDM中继系统。该方法对中继两端链路的非对称活跃子载波进行配对,在配对的子载波上发送物理层网络编码信息。仿真结果表明,该方法显著改善了误码率性能,消除了原有的误码平台并且提高了系统的吞吐量性能。

Since subcarrier suppression, known as an efficient approach to improving BER performance of OFDM transmission system, now attracts much attention from acdemic circles. Due to the independence of links between terminals and relay, the direct use of subearrier suppression in a two-way relay network would cause the asymmetry of active subcarriers in two symmetrical sides, thus leading to infeasible net- work coding of large numbers of subcarriers. In this paper, a decode-and-forward PLNC OFDM relaying systemjoint subcarrier suppression and subearrier pairing is proposed. In this method, active subcarriers a- symmetrical to two sides of relay are paired. Simulation results indicate that this new method is superior to the traditional methods in both BER and throughput performance and eliminate the BER floor as well.