Conference Paper

Impact of Acoustic Propagation Models on Depth-Based Routing Techniques in Underwater Wireless Sensor Networks

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Abstract

Depth-based routing protocols play a key role in assuming realistic approach by considering the continuous node movement in aqueous environment. The performance attributes of depth-based routing protocols highly depend upon the depth information of sensor nodes. Although this information is not prioritized by all acoustic models to estimate channel conditions, however, some notable models consider depth information of nodes. In this paper, we discuss the analysis of two major acoustic propagation models of Thorp and Monterey-Miami Parabolic Equation (MMPE) in predicting transmission losses with four notable depth-based routing techniques of Depth-Based Routing (DBR), Energy Efficient Depth-Based Routing (EEDBR), Adaptive Mobility of Courier nodes in Threshold-optimized Dbr (AMCTD) and Improved Adaptive Mobility of Courier nodes in Threshold-optimized Dbr (IAMCTD). We highlight the complexity and accuracy of these models in estimating the performance of higher layer protocols. Simulations show that physical layer parameters highly affect the performance of routing layer protocols as predicted by later propagation models. Results also prove that distant transmissions cause high propagation losses which are overcome by latest depth-based routing protocols. These protocols analyze the results of MMPE model to enhance upper channel limits and network lifetime.

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... Where, α is the absorption coefficient and d is the distance between the sender and receiver nodes. Another important factor, NL [35] consists of four noise components which are calculated by using the equations below. It depends upon frequency of the signal: ...
... Acoustic propagation models examine path loss and transmission loss in an aqueous channel. Recently proposed models such as MMPE [35] and thorp model consider depth, signal height and combined noises in aqueous environment. However, some models regard frequency and bandwidth efficiency as the deciding factors for variations in path loss and delay. ...
... We study the effects of acoustic channel characteristics on the speed and propagation delay of the signal. As we know that the propagation delay for acoustic signal is five times greater [35] than the Radio Frequency (RF) signals due to multi-path and fading effects and it depends on the attenuation coefficient due to high Bit-Error-Rate (BER) in aqueous conditions. Fig. 3.1 shows the description of propagation delay. ...
Thesis
Full-text available
In Underwater Wireless Sensor Networks (UWSNs), the major challenges are high propagation latency in data transmission, dynamic topology of nodes due to wave movements and high power consumption of acoustic modem. Depth based routing as a subcategory of localization-free routing protocols, is designed to cope with the above mentioned challenges. In this subcategory, sensor nodes use their depth information to forward data towards sinks, which are stationed at the surface of aqueous environment. The most widely used depth-based routing protocols are Depth Based Routing (DBR) and Energy Efficient Depth Based Routing (EEDBR). DBR has low stability period due to increased data flooding in medium-depth nodes. Whereas in EEDBR, network lifetime expires quickly due to unnecessary data forwarding and overloaded low-depth nodes where network lifetime is the duration between network initialization and complete energy exhaustion of all the nodes. In this thesis, we overcome above mentioned deficiencies of DBR and EEDBR using the mobility of courier nodes in our proposed routing scheme; Adaptive Mobility of Courier nodes in Threshold-optimized Depth-based-routing (AMCTD). We also propose Forwarding-Function (FF) based routing protocol; improved Adaptive Mobility of Courier nodes in Threshold-optimized Depth-based-routing (iAMCTD). In order to tackle high path loss and increased propagation latency, we calculate optimal Holding Time (HT) by using devised parameters; Signal Quality Index (SQI), Energy Cost Function (ECF) and Depth Dependent Function (DDF).
... The information needed by routing protocols include the location information of the sensor nodes and some need the depth information. Depth threshold delimits the number of qualified neighbors for data forwarding by picking neighbors in a particular range [11]. For calculating the depth information, sensor nodes are equipped with depth sensors. ...
... In [10], the authors have identified the confinements of various routing algorithms used for UWSNs and the design issues for efficient routing algorithm were also discussed. In [11], the authors have analyzed two major acoustic propagation models of Thorp and Monterey-Miami Parabolic Equation (MMPE) to determine the packet drop for DBR, EEDBR, AMCTD, and IAMCTD. ...
... where, α is the absorption coefficient and d is the distance between sender and receiver nodes. Another important factor, NL [27], consists of four noise components, which are calculated by using the equations given below. NL depends upon frequency of the signal: ...
... Acoustic propagation models examine path loss and transmission loss in an aqueous channel. Recently proposed models such as MMPE [27] and the thorp model consider depth, signal height and combined noises in aqueous environment. However, some models regard frequency and bandwidth efficiency as the deciding factors for variations in path loss and delay. ...
Article
Full-text available
Appropriate network design is very significant for Underwater Wireless Sensor Networks (UWSNs). Application-oriented UWSNs are planned to achieve certain objectives. Therefore, there is always a demand for efficient data routing schemes, which can fulfill certain requirements of application-oriented UWSNs. These networks can be of any shape, i.e., rectangular, cylindrical or square. In this paper, we propose chain-based routing schemes for application-oriented cylindrical networks and also formulate mathematical models to find a global optimum path for data transmission. In the first scheme, we devise four interconnected chains of sensor nodes to perform data communication. In the second scheme, we propose routing scheme in which two chains of sensor nodes are interconnected, whereas in third scheme single-chain based routing is done in cylindrical networks. After finding local optimum paths in separate chains, we find global optimum paths through their interconnection. Moreover, we develop a computational model for the analysis of end-to-end delay. We compare the performance of the above three proposed schemes with that of Power Efficient Gathering System in Sensor Information Systems (PEGASIS) and Congestion adjusted PEGASIS (C-PEGASIS). Simulation results show that our proposed 4-chain based scheme performs better than the other selected schemes in terms of network lifetime, end-to-end delay, path loss, transmission loss, and packet sending rate.
... One of the most essential routing protocols in UWSN is the Depth Based Routing Protocol (DBR). DBR is a routing algorithm that attempts to send a data packet from one source node to multiple sinks [12,13]. The DBR protocol involves the using a multi-sink architecture in which a number of underwater sensor nodes send information to the sink nodes. ...
Article
Full-text available
Routing protocols for underwater wireless sensor networks (UWSN) and underwater Internet of Things (IoT_UWSN) networks have expanded significantly. DBR routing protocol is one of the most critical routing protocols in UWSNs. In this routing protocol, the energy consumption of the nodes, the rate of loss of sent packets, and the rate of drop of routing packets due to node shutdown have created significant challenges. For this purpose, in a new scenario called FB-DBR, clustering is performed, and fuzzy logic and bloom filter are used in each cluster’s new routing protocol in underwater wireless sensor networks. Due to the fuzzy nature of the parameters used in DBR, better results are obtained and bloom filters are used in routing tables to compensate for the deceleration. as the average number of accesses to routing table entries, dead nodes, Number of Packets Sent to Base Station (BS), Number of Packets Received at BS, Packet Dropped, and Remaining Energy has improved significantly.
... Transmission loss and path loss in aqueous channel can be analysed by using the acoustic propagation models (Javaid et al., 2015;Jafri et al., 2014b). Thorps and MMPE are prorogation models proposed considering the height of single, combined noises and depth level in aqueous environment. ...
... Transmission loss and path loss in aqueous channel can be analysed by using the acoustic propagation models (Javaid et al., 2015;Jafri et al., 2014b). Thorps and MMPE are prorogation models proposed considering the height of single, combined noises and depth level in aqueous environment. ...
... Transmission loss and path loss in aqueous channel can be analysed by using the acoustic propagation models (Javaid et al., 2015;Jafri et al., 2014b). Thorps and MMPE are prorogation models proposed considering the height of single, combined noises and depth level in aqueous environment. ...
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The advance management of the power supply to load such as in homes, offices etc. and power from source to central network in smart grid system with lowest possible loss is considered here in this paper using the concept of energy internet. It also includes the complete details of power flow and control. In this paper, the efficiency of transmission is increased by using energy routers based on open shortest path first (OSPF) protocol, a new concept in the field of energy internet. By using energy local area network (e -LAN) concept, all the energy routers are connected by using OSPF protocols and virtual circuit concept theory. An algorithm is proposed for efficient power transmission and effective selection of sources to minimize the overall cost in the network.
... A decrease in the interference region results in an increase of the delivery probability and network throughput. In [34], the authors employed various acoustic propagation models to study the detailed performance of DBR and its improved versions. They discuss the prominent models which are used to analyze the channel losses, Doppler spread and ray tracing. ...
Thesis
Full-text available
Underwater Sensor Networks (UWSNs) employ sensor nodes and acoustic communication to detect physical attributes of water such as temperature, pressure, etc. Research on UWSNs has emerged thanks to their wide spectrum of applications which includes the management of the oil reservoirs and the prevention of aqueous disasters, as well as military surveillance. The dynamic conditions of water, the energy constraints and the high error probability during data transmission are prominent challenges in the design of routing protocols in UWSNs. One of the main routing schemes is Depth-based routing (DBR) that performs a specialized anycast routing to the surface sinks, based along the depth measured from pressure sensors. In this thesis, we study and optimise some routing protocols for UWSNs, specifically those based on DBR. To this aim, we designed a novel simulator for studying DBR and its enhancements. Our simulator is based on AquaSim-NG and NS-3 (Network Simulator). With respect to the state of the art, we implemented the cross-layer communication required by DBR and an accurate representation of the operational modes of acoustic modems with the associated energy consumption. We developed some analytical models for UWSNs with the aim of (i) identifying the optimal transmission range for sensor nodes given the state of the system, (ii) finding the optimal number of hops between the source and destination under various network settings, (iii) evaluating the role of the depth threshold in the definition of the routing scheme. In this work, a pivotal role is played by the energy consumption and expected lifetime of the network. Finally, based on our findings, we designed the Residual energy-Depth (RD) routing protocol which improves the network lifetime.
... Because of those factors of UWSNs, the protocols used on the land cannot be directly applied in UWSNs, especially for routing protocols. Therefore, designing a routing protocol special for UWSNs is necessary [10][11][12]. ...
Article
Full-text available
With the development of wireless networks and increasingly interest of people in underwater resources and environment, UWSNs are being paid more and more attention. Because of the characteristics of underwater channel and acoustic signal, the protocols used in the terrestrial networks cannot be directly used in UWSNs. In this paper, a reliable and energy-efficient routing protocol based on SHS and coding, called RSHSC, is proposed. Firstly, regular nodes are assigned to cluster heads according to simplified harmony search algorithm. Secondly, partial network encoding is introduced and the next two-hop information is considered when data packets are transmitted to sink nodes from the source node. Only the best next-hop forwards data packets. All data packets from neighbor nodes are used for decoding. Thirdly, two schemes of updating routing are designed and compared. Lastly, extensive simulations prove RSHSC is effective in improving reliability and decreasing energy consumption.
... The transition delay between the sending and receiving status of the acoustic modem is selected to be 1.5 s, modem synchronization delay is 0.5 s and forwarding delay is 1 s [22,23]. The initial energy of each node is assumed to be 70 J [56]. A four-state Markov model has been used to represent the acoustic channel over each link. ...
Article
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In this paper, we investigate a hybrid automatic repeat request (ARQ) scheme for reliable data transfer in multi-hop underwater acoustic sensor networks (UASNs). The proposed scheme combines Reed-Solomon-based packet level erasure coding and selective retransmissions to achieve high reliability and energy efficiency. We also describe how to select the code rate (i.e., number of encoded packets) for a given message block consisting of m packets. The paper evaluates the performance of the proposed scheme by taking into account the underwater-specific characteristics such as distance dependent bandwidth, acoustic spreading effects, propagation loss, and fading effects. Simulation results demonstrate that the proposed scheme can significantly improve the network throughput and energy efficiency while reducing the end to end delay considerably.
... where, T T X is the transmission time in seconds. In acoustic channel, delay can be computed by using end-to-end delay model 12 . In this model, the main component is propagation delay T P . ...
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Other techniques and general topics
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Communication between wireless sensor devices and gnu radio
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