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This paper provides an overview of more than 12 years of underwater acoustic communication research at the Sonar Department of TNO The Hague. The research covered both point-to-point links and relay networks, from long-range covert communication to short-range high-data-rate communication, for both civil and military applications. The current scientific focus is on wideband modulations and waveforms...
This paper presents an integrated underwater navigational algorithm for autonomous underwater vehicles using two movable surface acoustic reference stations which can transmit data packet to the AUV via acoustic modem with synchronous timer. This paper proposes a measurement model with the two range measurements that can improve the performance of an IMU-DVL (inertial measurement unit - Doppler velocity...
Underwater Wireless Sensor Networks (UWSNs) are expected to support a variety of civilian and military applications. Sensed data can only be interpreted meaningfully when referenced to the location of the sensor, making localization an important problem. In terrestrial WSNs, this can be achieved through a series of message exchanges (via RF communications) between each sensor and Global Positioning...
A mobicast, or called as mobile geocast, problem in three-dimensional (3D) underwater sensor networks (USNs) is investigated in this paper, which aims to overcome the hole problem and minimizes the energy consumption of the sensor nodes while maximizing the data collection. In this work, all underwater sensor nodes are randomly distributed in a 3D underwater environment in the sea to form a 3D USN...
In order to get reliable communication no matter under the water or above the surface, a kind of multi channel and distributed wireless communication network architecture for UUVs was presented. This network architecture includes underwater communication, surface communication and internal communication. Underwater communication is acoustic modem, and the surface communication consists of RF, Wi-Fi,...
In an underwater environment signal propagation for the acoustic channel is subject to major multipath effect. Therefore, most underwater communication schemes require that the position of the transmitter or receiver is fixed while using directional antennas in order to ensure high signal-to-noise ratio. However, such a requirement hinders node discovery and ad-hoc formation of underwater networks...
Mobile swarms of autonomous underwater vehicles (AUV) have exciting potential for extending current AUV applications and adding new possibilities to the working environment of the oceans. For swarm operations to occur, fast reliable communication between all vehicles within the swarm is needed. The challenge for underwater communication is the very different and unique characteristics of the channel...
Underwater sensor network (USN) enables various services implemented over terrestrial wireless sensor network previously and underwater robot control service is one of the applications of USN. For wirelessly controlling an underwater robot, development of an underwater acoustic modem for transmitting robot control frame as well as analysis of the robot control protocol should be carried out properly...
In this paper, we address the challenging topic of target detection and tracking in underwater environments, proposing a behavior-based algorithm suitable for both fixed and moving targets. Taking into account the stringent constraints of the acoustic underwater channel, we apply this method to fleets of collaborative AUVs. The resulting control strategy is able to benefit from the behavior-based...
The research being conducted in the Center for Secure and Resilient Maritime Commerce (CSR), a DHS National Center of Excellence for Port Security examines some basic science issues and emerging technologies to improve the security of ports and inland waterways, as well as coastal and offshore operations. This research follows a layered approach utilizing above water and underwater surveillance techniques...
Time reversal mirror technology is a new method of localization, which may be applied to target detection and localization effectively. Intensive coherent interference will conduct the autonomous underwater vehicle focus on the strong interference and reduce the detection probability. This paper brings out time reversal passive shielding and focusing (TRPSF) method with two vector-sensors' vertical...
Underwater vehicles are typically operated using a tether or a slow acoustic link. We present an underwater optical communication system that enables a high-throughput and low-latency link to an underwater robot. The optical link allows the robot to operate in cluttered environments without the need for a tether. We demonstrate the performance of the system in a number of experiments which characterize...
Cooperative navigation for multi-UUV is localizing all members of a team of UUVs by proprioceptive and exteroceptive sensors through acoustic link among UUVs. In the Leader-Fellow structure, the master UUV is equipped with high accuracy sensors, the slave UUV is equipped with low precision sensors added with underwater sonar which provide relative observations between UUVs. The slaver gets the position...
Doppler Velocity Logs (DVLs) have become increasingly popular as navigation tools on remotely-operated vehicles, autonomous underwater vehicles, and human-occupied vehicles for over a decade. Using acoustic measurements to capture bottom tracking velocity measurements, DVLs can provide updated velocities which can in turn be used to calculate distance traveled. Thus, DVLs can perform as fundamental...
In this paper, we investigate the problem of localizing an underwater sensor node based on message broadcasting from multiple surface nodes. With the time-of-arrival measurements from a DSP-based multicarrier modem, each sensor node localizes itself based on the travel time differences among multiple senders to the receiver. Using one-way message passing, such a solution can scalably accommodate a...
In this paper, we compare communication schemes in scenarios of interest for underwater networks where multiple nodes collaborate towards the accomplishment of a target detection and tracking task. We consider two specific cases: in Scenario 1, a mobile Autonomous Underwater Vehicle (AUV) i) collects data from a set of fixed sensors deployed on the seafloor or ii) transmits data to the same nodes...
We consider cooperative positioning using acoustic range measurements for underwater sensor networks, including networks formed by autonomous unmanned underwater vehicles (UUVs). Severe multipath scattering from the seabed and ocean surface can result in inaccurate range measurements. In an inhomogeneous medium, such as sea water, the direct path is not necessarily the strongest path or the first...
Hermes is a two-way half-duplex underwater acoustic modem developed to transfer large amounts of information from an underwater asset to a surface operator, while being able to send command-and-control information to the underwater asset. In addition, this communication system must operate in very challenging environments such as busy ports and very shallow waters. Hermes must also provide the ability...
This is a simple underwater wireless communication system. In this system, land-based unit send radio waves to an underwater submarine model, and the underwater submarine model send commands by infra-red to the land-based motor unit to control the floating and submerged of the submarine. This system is centering on MCU(MSP430), respectively, achieving the signal generation, processing and automatic...
The maximum potential for underwater exploration rests within the use of multiple Autonomous Underwater Vehicles (AUVs) and tasks involving human diver-AUV coordination. Such tasks require dependable underwater wireless communications, which normally utilize the rapidly varying acoustic channel. Rigorous testing of underwater acoustic communication systems is necessary to develop a dependable network,...
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