Energy‐Spectral Efficiency Optimization in Wireless Underground Sensor Networks Using Salp Swarm Algorithm

Abstract

Achieving high data rate transmission is critically constrained by green communication metrics in Wireless Sensor Networks (WSNs). A unified metric ensuring a successful compromise between the energy efficiency (EE) and the spectral efficiency (SE) is, then, an interesting design criterion in such systems. In this paper, we focus on EE-SE tradeoff optimization in Wireless Underground Sensor Networks (WUSNs) where signals penetrate through a challenging lossy soil medium and nodes’ power supply is critical. Underground sensor nodes gather and send sensory information to underground relay nodes which amplify-and-retransmit received signals to an aboveground sink node. We propose to optimize source and relay powers used for each packet transmission using an efficient recent metaheuristic optimization algorithm called Salp Swarm Algorithm (SSA). Thus, the optimal source and relay transmission powers, which maximize the EE-SE tradeoff under the maximum allowed transmission powers and the initial battery capacity constraints, are obtained. Further, we study the case where the underground medium properties are dynamic and change from a transmission to another. For this situation, we propose to allocate different maximum node powers according to the soil medium conditions. Simulation results prove that our proposed optimization achieves a significant EE-SE tradeoff and prolongs the network’s lifetime compared to the fixed allocation node power scheme. Additional gain is obtained in case of dynamic medium conditions.

Hybrid Chaotic Salp Swarm with Crossover Algorithm for Underground Wireless Sensor Networks

“…The work [13] proves that the SSA-based scheme offers a better resource efficiency, given similar bandwidth and battery cost resources, compared with the traditional UWSN scheme. In this paper, we propose to further enhance the resource efficiency of the UWSN considered in [13] by modifying and improving the SSA. A novel algorithm called Hybrid Chaotic Salp Swarm with Crossover (HCSSC) is proposed to determine the optimal powers required by the source and relay nodes that enhance the network resource efficiency considering the initial nodes' battery capacities.…”

“…In nearby research works, SSA proves its efficiency in node localization optimization in WSN [17,18], energy consumption and lifetime optimization in WSN [19]. The work [13] proves that the SSA-based scheme offers a better resource efficiency, given similar bandwidth and battery cost resources, compared with the traditional UWSN scheme. In this paper, we propose to further enhance the resource efficiency of the UWSN considered in [13] by modifying and improving the SSA.…”

“…The primary objective is to jointly evaluate the efficient use of a limited frequency spectrum along with energy consumption. In UWSNs, this problem was first addressed in [13], where optimal powers used by underground sources and relay nodes for data forwarding to an aboveground base station were computed to maximize the energy and spectral efficiency tradeoff. The work [13] proposes a power allocation algorithm that utilizes the Salp Swarm Algorithm (SSA) [14] to solve the considered problem since the swarm intelligence models are interesting for various computer science fields [15,16].…”

“…In UWSNs, this problem was first addressed in [13], where optimal powers used by underground sources and relay nodes for data forwarding to an aboveground base station were computed to maximize the energy and spectral efficiency tradeoff. The work [13] proposes a power allocation algorithm that utilizes the Salp Swarm Algorithm (SSA) [14] to solve the considered problem since the swarm intelligence models are interesting for various computer science fields [15,16]. The SSA is suggested in [14] as a recent metaheuristic algorithm which outperforms many other metaheuristic algorithms through tests on 19 different benchmark functions.…”

A Wireless Underground Sensor Network Field Pilot for Agriculture and Ecology: Soil Moisture Mapping Using Signal Attenuation

“…Different types of topologies (e.g., underground-to-underground and underground-to-aboveground) have been modeled and tested experimentally [ 2 , 5 , 15 , 26 , 27 ], and the effect of soil properties on wireless underground signal propagation is well-studied [ 5 , 28 , 29 , 30 , 31 , 32 ]. Studies have included examining power consumption [ 30 , 33 , 34 , 35 ], as well as the deployment of communication protocols such as Mica [ 14 ], Zigbee [ 36 ], Wi-Fi [ 37 , 38 ], RFID [ 39 ], cellular [ 37 ], Sigfox [ 10 ], and Lora [ 12 , 35 ] for WUSNs. While experimental WUSN evaluations have been carried out in laboratory testbeds [ 9 , 22 , 40 , 41 , 42 ] and in some outdoor environments [ 10 , 12 , 43 , 44 , 45 , 46 ] and agricultural farms [ 14 , 19 , 32 , 43 , 47 , 48 , 49 , 50 ], testing has been limited, often with one or a few sensor nodes.…”