无线合作分集网络中节点覆盖范围的研究

Investigation on node's cooperative range in wireless network

通过对无线网络中节点覆盖范围的数学模型推导,得到直接传输情况下覆盖范围与中断概率的对应公式.仿真结果表明,当中断概率小于0.320时,理论值和实际仿真值误差不超过7.041%;通过对无线合作网络中的重复码放大前向(AF)、重复码译码前向(DF)、带反馈的放大前向(AFF)和编码结合(CC)的译码前向这4种合作方式进行节点覆盖范围的数学模型推导和仿真,结果表明,合作能显著提高节点的覆盖范围,且提高程度与中断概率成反比;模型还表明,中继节点到源节点的距离、中继节点到源节点和目的节点到源节点的夹角、传输码率对覆盖范围有较大的影响,影响程度由合作方式决定.

The equation of direct-transmission range and outage probability was given by the derivation of the mathematic model of node＇s communication range in wireless network. The numerical results show that the error between the theoretical value and the Monte Carlo simulation value is less than 7. 041% when outage probability is less than 0. 320. Then a variety of cooperative range based on some typical protocols such as amplify-and-forward（AF）, decode-and-forward （DF）, AF-with-feedback（AFF）, coded-cooperation（CC） were illustrated. The cooperative range is much larger than direct-transmission range and the enlargement contrasts to outage probability. The distance between a source and its relay, the plane included angle at the source and transmission rate have a dominant effect on cooperative range, which depends on a certain cooperative protocol.