可变分集增益的分布式空时传输方案

Distributed space-time transmission scheme with variable diversity gain

为了使多用户协作通信网络中的分布式空时码获得更高的分集增益,提出一种可变分集增益的传输方案。在已经存在的分布式空时码的基础上通过增加转发节点的数量,利用在时间与空间(可利用的转发节点)上的重复编码来获得分集增益的提高。导出新方案分集阶数的计算公式,利用最大似然译码算法分析接收信噪比特性。计算机模拟仿真实验显示,新方案可获更高分集增益,且在不降低分集阶数的情况下能通过降低信号周期来降低信号传输过程中对静态信道的要求。

In order to make distributed space-time codes of multi-user cooperative networks achieve higher diversity gain,a kind of transmission scheme with variable diversity gain is proposed.Based on the existing distributed space-time codes,the Scheme improves the diversity gain by increasing the number of relay nodes and repeating the code across time and space（available relay nodes）.The formula to calculate the diversity order of the new scheme is derived.The ML decoding algorithm is then used to analyze signal-to-noise characteristic.The computer simulations results show that the new scheme can not only achieve higher diversity gain but also have lower requirements of stationary channel in the whole transmission by decreasing the symbol period without changing the diversity order.