摘要
在认知无线电网络中,认知用户与主用户共同存在,认知用户在获得自己需要频谱资源的同时,会对主用户造成干扰,严重影响主用户的通信。为了减少对主用户的干扰,同时进一步提高频谱的利用效率,基于空域分集与自适应智能天线技术,提出利用空域分集方法来解决认知无线电网络的干扰抑制问题。通过均匀圆环阵列天线对干扰进行感知,并利用MUSIC算法对干扰到达方向进行二维估计,在此基础上进行空间自适应波束形成,从而实现主用户和认知用户在空域上进行分离的目的。分析和仿真结果表明:采用该方法,可以有效抑制认知用户对主用户的干扰,实现认知用户与主用户同时访问频谱,提高频谱利用率。
In cognitive radio networks, there are scenarios where the cognitive users intend to communicate with each other by opportunistically utilizing the transmit spectrum originally allocated to the primary users. However, the cognitive users will interfere the primary user, and seriously influence the communication of them. In order to keep the interference to the primary users below a given threshold, and improve the spectrum utilization efficiency, an interference suppression method in cognitive radio networks is proposed based on spatial diversity and adaptive smart antenna technology. Through uniform circular array antenna for interference-a- ware,and by using MUSIC algorithm for the two-dimensional direction of arrival estimation, it can form spatial adaptive beamforming so as to separate the primary users from the cognitive users in the spatial domain. The simulation results show that this method can effectively suppress the interference on the primary users from the cognitive users, and it can guarantee the cognitive users to access the spectrum simultaneously with the primary user, and improve efficiency of spectrum utilization.
出处
《电波科学学报》
EI
CSCD
北大核心
2010年第4期767-772,814,共7页
Chinese Journal of Radio Science
基金
北京市自然科学基金(4102040)
国家自然科学基金(60773074)
863计划(2007AA01Z213和2009AA01Z209)
