首先分析了TDMA协议和HFTP协议2种短波MAC协议的原理,结合2种协议的优缺点,针对短波天波通信数据传输可靠性低的特点,在TDMA协议的基础上设计了一种适应于短波信道的TP-TDMA协议。运用排队理论建立了各协议时延的数学模型,通过解析的方法衡量各因素对时延的影响,并以信道误码率、节点数量、业务量大小为变化条件,对时延进行了仿真比较。结果表明:TP-TDMA协议相比TDMA协议和HFTP协议,在短波信道条件下,随着信道误码率、节点数目及业务量的逐渐增加,TP-TDMA协议都表现出更优异的性能。
First, the principles of TDMA protocol and HFTP protocol are analyzed. Aimed at the features that fluctuations are fast and high frequency (HF) communication via sky-wave propagation is faded, a TP -TDMA protocol based on TDMA protocol is designed combined with the advantages and disadvantages of two kinds of HF MAC protocol. A mathematical model of time delay is established by using queuing theo- ry. The influence of different factors on the time delay is discussed by the analytical method. The results show that the TP-TDMA protocol has more excellent performance than that of the TDMA protocol and HFTP protocol in the HF channel with the increase of the value of channel error rate, node number and traffic.