Source:   Swedish Research Council Date:   2005-04-07

Print this page Email to friend

New Technology For Navigating Without GPS

A new method for navigation at sea, independent of GPS, is being put forward in a dissertation from Linköping University.

	Related News Stories
	New Technology Separates Cancer From Benign Tumors (November 4, 2002) -- A group of researchers in Trondheim, Norway, are the first in the world to use in vivo magnetic resonance spectroscopy (MRS) to separate benign tumors from cancer. Ingrid Susann Gribbestad shows, in ... > full story Microelectromechanical Technology -- Meshless Numerical Methods Simplify Device Design And Analysis (August 18, 2000) -- University of Illinois engineers have designed numerical techniques that can help analyze MEMS devices and assist in the development of better computer simulation ... > full story Technique Reduces Time Spent On Radiation Doses (September 18, 2003) -- Researchers at Washington University in St. Louis have developed a technique that drastically decreases the time a radiologist spends calculating radiation dosages and also provides a more carefully ... > full story Simulation Uses Quantum Mechanics To Understand Nanoelectronics (July 8, 1999) -- A computer simulation developed at the University of Illinois is helping scientists better understand the strange world of nanoelectronics -- where a single electron can control a device, but quantum ... > full story > more related stories Related section: Matter & Energy

Today merchant marine, military, and recreational boat traffic all rely on the global satellite system GPS to determine their position at sea. But sometimes information from the system is incorrect. Poor visibility or lax attention can then spell disaster.

GPS can be jammed, either unintentionally or intentionally. Signals from the satellites can be interfered with by ice build-up on the vessel's antennas, by other communication equipment, or by physical obstacles. Submarines cannot usually use the system.

Doctoral student Rickard Karlsson at the Center for Control and Communication describes in his thesis how modern, simulation-based methods of treating signals can be used to monitor and, if necessary, to take over the GPS function on a vessel.

This technology, unique in the world, requires no external infrastructure and is not susceptible to interference. Instead, the vessel's own radar is used to measure the distance to surrounding shores, and this data is then compared with a digital sea chart. In a submarine, information from sonar equipment is compared with a digital depth chart. In combination with data about the movement of the vessel, the correct position can be calculated.

The method is based on a mathematical algorithm, a so-called particle filter, which is installed as a program in the vessel's computer system. There is no need for any further hardware to be installed beyond what is already on board. Preliminary trials show that the method works just as well as GPS in navigating an archipelago.

The dissertation Particle Filtering for Positioning and Tracking Applications deals with several other uses of the same principle: positioning industrial robots, tracking vehicles from another vehicle to avoid collisions, and tracking boats and ships from an airplane.

This story has been adapted from a news release issued by Swedish Research Council.

Can't find it? Try searching ScienceDaily or the entire web with:

Web sciencedaily.com