基于码分多址接入的无线移动自组网吞吐量性能分析

窄带移动自组网在同一时隙内只能有一个节点发送数据，否则会导致碰撞，降低网络吞吐量性能。移动自组网中引入码分多址技术可以显著提高吞吐量，将网络状态建模为马尔可夫链，提出一种多址干扰和噪声共同影响下的吞吐量性能分析方法，综合考虑了扩频码同步和解调误码率的影响。数值仿真表明提高信噪比、编码纠错能力，以及增加扩频码长度均能提升网络吞吐量性能，低信噪比时编码纠错能力对性能提升比高信噪比时明显。编码纠错能力和扩频码长度均存在最佳的取值范围，超过此范围继续提高则对吞吐量性能的提升作用不再明显，因此需要根据实际环境优化网络参数。提出的新的分析方法具有更加普遍的适用性，更符合网络的真实情况，仿真实验对网络设计具有参考价值，可以用作网络参数选取的理论依据。

Packet Throughput of CDMA based Mobile Ad hoc Networks

For narrowband mobile ad hoc networks, only one node can transmit data in the same time slot, otherwise it will lead to collision and reduce the network throughput performance. The introduction of code division multiple access technology in ad hoc networks can significantly improve the throughput. Based on the Markov model of network state, the throughput performance analysis method is proposed, which is based on the multiple access interference and background noise. Numerical simulations show that the performance of the network throughput can be increased by increasing the signal to noise ratio, the error correcting capability and the length of the spreading code. The coding error correcting capability and the spreading code length have the best value range, so the network parameters need to be optimized according to the actual environment. The new analysis method proposed has more general applicability and is more consistent with the real situation of the network, and the simulation results can be used as the theoretical basis of network design.