Energy-Efficient Cooperative Spectrum Sensing in Cognitive Satellite Terrestrial Networks
Energy-Efficient Cooperative Spectrum Sensing in Cognitive Satellite Terrestrial Networks
复制标题
认知卫星地面网络中的节能协作频谱感知
DOI：
10.1109/access.2020.3020846
复制
发表时间：
2020-01-01
期刊：
影响因子：
3.9
通讯作者：
Gou, Liang
中科院分区：
文献类型：
--
作者：
Hu, Jing;Li, Guangxia;Gou, Liang
认知卫星地面网络具有无缝覆盖和缓解频率稀缺的能力，成为未来通信网络的一个有前途的候选者。在认知网络中，频谱感知在检测信道状态以实现机会利用方面发挥着重要作用，协作频谱感知可以提高感知性能。此外，对于电池供电的卫星移动的终端来说，降低能耗成本是至关重要的。针对这一问题，提出了一种基于感知的认知卫星地面网络，将认知卫星地面网络与分布式协作频谱感知网络相结合。具体来说，我们专注于能源效率的协作感知在SCEST-T，最大限度地提高能源效率（EE）的认知卫星网络的平均吞吐量和平均能耗之间的权衡。在该算法中，感知节点的能量检测阈值和融合规则阈值影响平均吞吐量和平均能耗。因此，本文的目标是确定传感器节点的能量检测阈值和融合的规则阈值，以实现最大的EE。我们首先研究了当传感器节点的能量检测阈值给定时，融合的规则阈值的EE公式，并将EE的比率型目标函数转化为参数公式。随后，通过探索两种公式之间的关系，并利用参数公式的单调性，提出了一种求解原问题的最优融合规则阈值的算法。研究了感知节点能量感知阈值的最优公式，讨论了感知时间和分布式协作终端数量对能量感知的影响。最后，通过数值仿真对所提方法的性能进行了评估。
Having the ability to provide seamless coverage and alleviate the frequency scarcity, the cognitive satellite terrestrial network becomes a promising candidate for future communication networks. In the cognitive network, spectrum sensing plays an important role in detecting the channel state for opportunistic utilization, where cooperative spectrum sensing is employed to improve the sensing performance. Additionally, it is critical for battery-powered satellite mobile terminals to diminish energy consumption costs. In this regard, this paper proposes a novel sensing-based cognitive satellite terrestrial network (SCSTN), which integrates the cognitive satellite terrestrial network with the distributed cooperative spectrum sensing network. Specifically, we focus on energy-efficient cooperative sensing in the SCSTN, which maximizes the energy efficiency (EE) of the cognitive satellite network by a tradeoff between the average throughput and the average energy consumption. In the SCSTN, the energy detection threshold of the sensing node and the rule threshold of fusion affect the average throughput and the average energy consumption. Hence, the objective of this paper is to identify the energy detection threshold of the sensing node and the rule threshold of fusion to achieve the maximum EE. We first study the EE formulation of the rule threshold of fusion when the energy detection threshold of the sensing node is given, and transform the ratio-type objective function of EE into a parametric formulation. Subsequently, by exploring the relationship between the two formulations and making use of the monotonicity of the parametric formulation, an algorithm to obtain the optimal rule threshold of fusion for the original problem is developed. Furthermore, we study the optimal formulation of the energy sensing threshold of the sensing node and discuss the effect of the sensing duration and the number of distributed cooperative terminals on the EE. Lastly, the performance of the proposed method is evaluated through numerical simulation results.