非正交多址中继系统复数域网络编码优化设计

无线中继与网络编码是提高通信系统数据可靠性和吞吐率的重要技术手段,重点研究了单中继非正交多址系统复数域网络编码的优化设计问题.首先,在限制源节点和中继节点的总发送功率并假设各个源节点发送功率相同的条件下,证明了当源节点与中继节点发送功率相等时基于复数域网络编码的单中继非正交多址系统误符号率(SEP)性能最佳.其次,以编码增益为目标函数,提出了一种复数域网络编码的优化设计方法.与已有的复数域网络编码系数设计方法相比,此方法能满足任意源节点个数条件下复数域网络编码系数的优化设计要求,同时可以有效地避免因为网络编码系数选择不当造成信号重叠的现象,提升和改进系统的SEP性能.

Optimized design of complex field network coding scheme in non-orthogonal multiple access relay system

Wireless relay and network coding are two fundamental techniques to enhance the throughput of wireless communication system.The optimized design of complex field network coding scheme in non-orthogonal multiple access single relay system was addressed.Firstly,given the total transmitting power at all source nodes (equal transmitting power at every source node was assumed) and the relay node,the system might achieve the minimal symbol error probability (SEP) when the total transmitting power were equally allocated to all source nodes and relay node.Secondly,the choice of the complex field network coding coefficients plays an important role in the achieved SEP for the non-orthogonal multiple access single relay system was disclosed,and the optimized coding coefficient design in terms of the maximal coding gain were presented for arbitrary number of source nodes.It was shown that,the similarity of network coded signal of multiple source signals could be effectively avoided by using the optimized coding coefficient,which accounted for the realized performance improvement in the non-orthogonal multiple access single relay system.