无线Ad Hoc网络中双向传输容量的研究

Bidirectional Transmission Capacity in Wireless Ad Hoc Networks

目前对于基于双向传输信道的无线Ad Hoc网络传输容量的研究还很少,主要原因是无法得到传输容量的闭合表达式,无法准确地研究各种网络参数对传输容量的影响.针对这一情况,使用随机几何理论建立无线Ad Hoc网络双向传输模型,并对瑞利衰落信道时双向传输成功概率和双向传输容量的闭合表达式进行了理论推导.数值仿真结果表明:单次传输的成功概率受多个网络参数的影响,实际网络中通信密度的增加会导致通信成功概率的迅速下降;双向传输容量主要受到网络允许的最大通信失败概率的影响,当最大通信失败概率较小时,双向传输容量随着最大通信失败概率的增加而显著增大,但是此时通信质量也会下降,因此需要选择合适的最大通信失败概率以便兼顾通信质量和双向传输容量.

The research of the transmission capacity in wireless Ad Hoc networks based on bidirectional chan -nels grew slowly.The closed-form expression could not be obtained.As a result,the relationship between the transmission capacity and the network parameters could not be expressed exactly.To solve the problem, the system model of bidirectional transmission in wireless Ad Hoc networks,was proposed to redefine the bidirec-tional transmission capacity based on the symmetrical bidirectional transmission channel, and to derive the probability of successful transmission and transmission capacity for bidirectional transmission.Numerical re-sults showed that,the probability of successful transmission for single transmission was affected by some net-work parameters,and was mainly determined by the density of transmission pair with which the probability of successful transmission would increase.The bidirectional transmission capacity was mainly determined by the maximum outage probability.When the maximum outage probability was a small value,the bidirectional trans-mission capacity would increase with maximum outage probability, while the quality of communication would reduce,so how to choose a suitable maximum outage probability was very important in real networks.