一种正交时频码及其应用

Orthogonal Time-Frequency Code and Its Application

为了提高系统容量,简化接收机结构,构造了一种新的正交码组——正交时频码,并基于提出的正交码构造了一个新的多载波码分多址方案.该方案采用正交时频码作为地址码,不仅提高了码字利用率,而且提高了系统的总容量,同时简化了信道估计和载波恢复算法.接收机采用Rake接收机结构不仅可以获得频率分集增益,而且可以同时完成信道估计和载波恢复.从理论上分析了正交时频码的构造和特性;其次给出了系统发射机和接收机结构以及仿真结果.仿真结果与理论分析结果相符.

In order to improve the system capacity and simplify the receiver structure of traditional multi- carrier scenarios, a new orthogonal code called orthogonal time-frequency code was produced. Thereaft- er, a multi-carrier code division multiple access scheme was proposed. This new scheme employs orthog- onal time-frequency code as its address code. It can not only improve the utilization of the codeword, but also can enhance the capacity of system. The frequency diversity gain in frequency selective fading chan- nel can be obtained without coding by employed the Rake receive, that can also complete channel estima- tion and carrier recovery simultaneously. Simulation is coincided with the analysis.