Sensing-Throughput Tradeoff for Cognitive Radio Networks
Sensing-Throughput Tradeoff for Cognitive Radio Networks
复制标题
DOI：
10.1109/icc.2007.882
复制
发表时间：
2007-06
期刊：
影响因子：
--
通讯作者：
Ying-Chang Liang;Yonghong Zeng;E. Peh;Anh Tuan Hoang
中科院分区：
文献类型：
--
作者：
Ying-Chang Liang;Yonghong Zeng;E. Peh;Anh Tuan Hoang
在认知无线电网络中，当主网络（用户）当前未使用频段时，允许次网络（用户）使用这些频段。为了支持这一功能，次用户需要感知射频环境，一旦发现主用户处于活动状态，次用户必须在一定时间内腾出信道。与信道感知相关的有两个参数：检测概率和虚警概率。检测概率越高，主用户就能得到越好的保护。然而，从次用户的角度来看，虚警概率越低，信道可被复用的机会就越多，因此次用户可实现的吞吐量就越高。在本文中，我们研究次用户的感知能力和可实现吞吐量之间的基本权衡。特别是，我们研究感知时隙持续时间的设计，以便在主用户得到充分保护的约束条件下使次用户的可实现吞吐量最大化。利用能量检测方案，我们证明确实存在一个提供最佳权衡的最优感知时间。基于所提出的感知 - 吞吐量权衡方法，还对协作感知进行了研究。通过计算机仿真对所提出的权衡方法进行了评估。
In cognitive radio networks, the secondary network (users) are allowed to utilize the frequency bands of primary network (users) when they are not currently being used. To support this function, the secondary users are required to sense the radio frequency environment, and once the primary user is found to be active, the secondary users have to vacate the channel within certain amount of time. There are two parameters related to channel sensing: probability of detection and probability of false alarm. The higher the detection probability, the better the primary users can be protected. However, from the secondary users' perspective, the lower the false alarm probability, the more chances the channel can be reused, thus the higher the achievable throughput for the secondary users. In this paper, we study the fundamental tradeoff between sensing capability and achievable throughput of the secondary users. Particularly, we study the design of sensing slot duration to maximize the achievable throughput for the secondary users under the constraint that the primary users are sufficiently protected. Using energy detection scheme, we prove that there indeed exists an optimal sensing time which provides the best tradeoff. Cooperative sensing is also studied based on the methodology of the proposed sensing-throughput tradeoff. Computer simulations are presented to evaluate the proposed tradeoff methodology.