移动自组织网络中基于智能混合扩频的高效媒体访问控制方法

针对现存的大多数媒体访问控制(MAC)方法中断概率较高、大扩频增益的传输容量不佳等问题,在自组织网络中,提出一种基于智能混合扩频(SMSS)的MAC方法,其目的是利用稳健的调频扩频(DSSS)物理层降低远场干扰,运用智能慢跳频管理近场干扰。在低中断概率约束情况下,SMSS确保了在活跃接收器处的最小的信号与干扰加噪声比(SINR)的阈值。且SMSS不抑制空间中的任何节点,也不及时将它们释放出来。在跳频区大小可变的情况下,推导出传输容量的下限的数学模型。实验结果表明提出的SMSS MAC方法在传输容量方面具有较大优势,超过了ALOHA和基于保护区的扩频MAC协议。对于较小的扩频增益,其优势更为明显。

Smart Mixed Spread Spectrum Efficient Media Access Control Method in Mobile ad hoc Networks

Concerning that the interruption probability of most existing media access control (MAC) method is high and the transmission capacity under high spreading gain is not good, a MAC method based on smart mixed spread spectrum (SMSS) is proposed in ad hoc networks, with the aim to mitigate far field interference with the use of a robust direct sequence spread spectrum (DSSS) physical layer, while managing near field interference with the use of intelligent slow frequency hopping. SMSS ensures a minimum required the threshold of signal to interference plus noise ratio (SINR) at active receivers, under low outage probability constraints. SMSS does not inhibit any nodes in space neither thins them out in time. The mathematical model of the lower limit of the transmission capacity is derived in the case of variable frequency hopping. Experimental results show that the proposed MAC SMSS method has a great advantage of transmission capacity, more than that of ALOHA and MAC protocol based on protected areas. For smaller spread gain, the advantage is more obvious.