摘要
信道汇合是认知无线网络中次用户之间选择公共可用信道并建立通信链路的过程,是通信的前提和基础.针对次用户可用信道集合不同的异构认知无线网络难以保证信道汇合的问题,本文提出一套基于Galois域的信道汇合算法,具体包括面向全局信道和面向局部信道的汇合算法.该算法利用Galois域的加和乘运算生成周期性跳频序列,各周期序列包括顺时针方向遍历的信道、校验信道、逆时针方向遍历的信道3个阶段.面向局部信道的汇合算法是针对分布式环境中次用户无法获取全局信道信息而提出的.此外,本文对两种算法的最长汇合时间进行了理论分析.仿真结果表明,与已有算法相比,在全局信道和局部信道两种条件下,所提算法都具有更短的平均汇合时间.
Channel rendezvous is a prerequisite in cognitive radio networks, where secondary users choose a com- mon available channel and establish a connection. It is difficult to guarantee rendezvous in heterogeneous cognitive radio networks, where no universal channel set is shared among secondary users. In this paper, we propose two Galois-field-based channel hopping （GFCH） heterogeneous rendezvous algorithms： one is global-channel-oriented and the other is local-channel-oriented. The algorithms generate periodic channel-hopping sequences by perform- ing the operations of plus and multiply in the Galois field. The sequence in each period includes three phases： access all the channels in a clockwise direction, access the parity channel, and access all the channels in a counter- clockwise direction. As in a distributed environment, global channels may not be shared among secondary users;we then propose a local Galois-field-based channel hopping （L-GFCH） rendezvous algorithm utilizing only local available channels. Furthermore, we analyze the theoretical values of the maximum-time-to-rendezvous of GFCH and L-GFCH. Extensive simulations confirm that GFCH and L-GFCH outperform existing algorithms in terms of expected-time-to-rendezvous in global and local scenarios, respectively.
出处
《中国科学：信息科学》
CSCD
北大核心
2015年第6期752-765,共14页
Scientia Sinica(Informationis)
基金
中国科学院战略性先导科技专项(批准号:XDA06021000)资助
关键词
认知无线网络
信道汇合
跳频
异构网络
Galois域
cognitive radio network, channel rendezvous, channel hopping, heterogeneous network, Galois field
