Today’s and future communication systems in maritime rely on digital data communication between the ship and transceivers that are either on land, in air (satellite) or on sea. Analog voice communications is not an integrated part of future maritime communication system proposals. However, it is in general preserved in its functionality according to future maritime communication system proposal...

Underwater acoustic signal processing aims to reconstruct the shallow water acoustic channel from both direct arrival and delayed multipath reflections. This enables accurate acoustic communications in shallow water, such as between underwater autonomous vehicles (UAVs), which are essential for coastal surveillance and other applications. In this work, we take a previously implemented algorithm...

In this work a framework is presented for addressing the issue of intermittent communications faced by autonomous unmanned maritime vehicles operating at sea. In particular, this work considers the subject of predictive atmospheric signal transmission over multi-path fading channels in maritime environments. A Finite State Markov Channel is used to represent a Nakagami-m modeled physical fading...

Autonomous vehicles are playing increasing roles in the air / land / sea network of today’s battlespace. As the Navy’s lead laboratory for command, control, communications, ocean surveillance, and the integration of multiple-platform systems, Space and Naval Warfare Systems Center San Diego (SSC-SD) has a unique perspective on the development and utilization of vehicles for these applications. ...

A climate model which couples ocean, sea ice, atmosphere and land components is described. The component models are run as autonomous processes coupled to a flux coupler through a flexible communications library. Performance considerations of the model are examined, particularly for running the model on distributed-shared-memory machine architectures.

at the boundary between jurassic and cretaceous, because of late kimmerian movements, the sea ragressed from many areas of north and cantral iran, and many continental areas rose, which included a number of differentiated basins. the boundary between jurassic and cretaceous in these parts of iran is usually marked by a big diastem or by red, clastic and evaporitic sediments. the whole or part o...

Free Space Optical (FSO) communications pointing problems will be described and a solution presented. Conventional systems used in sea, land, and space are illustrated. Our integrated approach investigates three major problems areas: kinematics, structure, and dexterity. Their interrelationship will be discussed.

Radio communications between an Autonomous Underwater Vehicle at sea and shore-based base-stations faces considerable challenges particularly if the antenna on the vehicle does not rise high enough above the water surface. At distances comparable to the maximum line-of-sight distance to a base-station at a given height, situations may occur where the local relative sea wave heights produce inte...