Optimizing the number of relays for energy efficient multi-hop covert underwater acoustic cooperative networks. (June 2021)

• Record Type: Journal Article
• Authors: Chen, Yougan; Tang, Yuying; Liu, Junhui; Zhang, Xiaokang; Xu, Xiaomei
• Is Part Of: Applied acoustics. Volume 177(2021)
• Publication Date: 2021-06
• Subjects: Underwater acoustic -- Covert cooperative communication -- Energy consumption -- Probability of detection; Acoustical engineering -- Periodicals; Periodicals; 620.2
• DOI: 10.1016/j.apacoust.2021.107911
• Languages: English
• ISSNs: 0003-682X

Abstract

Abstract: Multi-hop underwater acoustic (UWA) cooperative networks can effectively reduce the energy consumption of the system, yet the covertness of communication is also greatly reduced since a spatial diversity gain can be obtained by both the intended receiver and the intercept detector. In this paper, we investigate how to select the optimal number of relays for multi-hop UWA cooperative networks, by considering both the low probability of detection ( P D ) and energy consumption. We derive the relationship between P D and the number of relays and then analyze the relationship between energy consumption and the number of relays for the system. To address the joint P D and energy consumption optimal problem, we define the energy consumption rate for multi-hop UWA systems by normalizing the energy consumed in single-hop UWA systems at the same source-to-destination distance. Then, we derive the range number of relays under the given P D and energy consumption rate. Moreover, we construct the objective function and derive the optimal number of relays by jointly addressing P D and the energy consumption rate. Finally, we simulate and analyze the impact of several parameters on P D and energy consumption, including the signal-to-noise ratio, working distance, position angle of interceptor and data length. The simulation results show that the number of relays for multi-hop covert UWA cooperative networks can take the value between 2 and 6 under a given condition, which can meet the covert communication requirement with a P D < 0.5, while the system energy consumption is relatively low.