School of Information and Communication Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China.
Sensors (Basel). 2018 Dec 10;18(12):4370. doi: 10.3390/s18124370.
In the distributed detection system with multiple sensors, there are two ways for local sensors to deliver their local decisions to the fusion center (FC): a one-bit hard decision and a multiple-bit soft decision. Compared with the soft decision, the hard decision has worse detection performance due to the loss of sensing information but has the main advantage of smaller communication costs. To get a tradeoff between communication costs and detection performance, we propose a soft⁻hard combination decision fusion scheme for the clustered distributed detection system with multiple sensors and non-ideal communication channels. A clustered distributed detection system is configured by a fuzzy logic system and a fuzzy c-means clustering algorithm. In clusters, each local sensor transmits its local multiple-bit soft decision to its corresponding cluster head (CH) under the non-ideal channel, in which a simple and efficient soft decision fusion method is used. Between clusters, the fusion center combines all cluster heads' one-bit hard decisions into a final global decision by using an optimal fusion rule. We show that the clustered distributed system with the proposed scheme has a good performance that is close to that of the centralized system, but it consumes much less energy than the centralized system at the same time. In addition, the system with the proposed scheme significantly outperforms the conventional distributed detection system that only uses a hard decision fusion. Using simulation results, we also show that the detection performance increases when more bits are delivered in the soft decision in the distributed detection system.
在多传感器分布式检测系统中，本地传感器向融合中心 (FC) 传输本地决策有两种方式：硬判决（one-bit hard decision）和软判决（multiple-bit soft decision）。与软判决相比，硬判决由于丢失了传感信息，因此检测性能较差，但具有通信成本较低的主要优势。为了在通信成本和检测性能之间取得折衷，我们针对多传感器、非理想通信信道的聚类分布式检测系统提出了一种软-硬组合判决融合方案。聚类分布式检测系统由模糊逻辑系统和模糊 C 均值聚类算法构成。在簇内，每个本地传感器在非理想信道下将其本地的多位软判决传输给其对应的簇头（CH），在簇内使用一种简单而高效的软判决融合方法。在簇间，融合中心通过使用最优融合规则将所有簇头的硬判决组合成最终的全局决策。我们表明，采用所提出方案的聚类分布式系统具有与集中式系统相当的良好性能，但同时消耗的能量比集中式系统少得多。此外，该方案的系统在硬判决融合的常规分布式检测系统上显著提高了检测性能。通过仿真结果，我们还表明在分布式检测系统中传输更多位软判决时，检测性能会提高。
