Are There Limits To Where Marine GPS Can Be Used?

When one considers the advances offered in a Marine GPS (Global Positioning System), the integration of satellite-based navigation systems for infrastructural or personal usage is virtually limitless. Since GPS was innovated by the U.S. Department of Defense, the broad implementation of the mapping technology has greatly enhanced precision in navigation. Popular for both commercial and recreational use, this 24 hour global navigation system offers up to 15 meters or 49 feet of geographic record.

Smart GPS in Marine Operations 
Orbiting satellites serving GPS Navigation send signals to user devices recording geographic position. GPS uses a cluster of satellites to ensure that the continuous transmission of radio frequency signals is accurate. GPS receiver reception of navigation information from satellite tracking of a position across time zones allows for the system to calculate the exact parallels of the location in relation to time according to the progression of the Earth’s orbit. 

Advantages offered in GPS navigation in the marine sector are extensive. The fact that prior to satellite positioning systems, mariners sought more efficient and effective mechanisms for tracking geographic activity in the maritime environment, has promoted the universal application of the mapping technology. Precursors to GPS such as lorans and SatNav saw limitations in reliability, range and weather tracking. GPS improved all three of these factors; advancing navigation, as well as positioning and course details. The launch of new versions of GPS has only increased the capacity of the mapping technology, now better in navigation and reporting than earlier releases of the product.

Smart operational capabilities designed to reinforce maritime mapping and reduce risk in course navigation, evidence the reliability of GPS as an indispensable tool. Exactitude in positioning is one of the key features of GPS. The geographic coordinate system is particularly well suited to the mapping of marine latitude and longitudinal coordinates. Satellite recognition of longitudinal meridian passing through the North Pole and South Pole reports degree of deviation from the Greenwich Prime Meridian (GMT). Latitudinal parallels running perpendicular to the Earth's polar axis are illustrated in relation to degree of deviation from Equatorial latitude. In GPS, compass direction waypoint marks from present not requiring alignment with physical landmarks, can be paused for future recall. 

Maritime Navigation Features 
Although there are now a variety of GPS products on the market, and some devices having better features than others, the results to satellite tracking are relatively the same. Information recorded by the satellites is transmitted to the GPS device and made available to users on a digital display. Devices with cartographic features offer an additional benefit in that the user can view the maritime location on an electronic chart that can be transferred to other applications. The portability of a handheld rather than a mounted GPS may increase flexibility, yet mounted devices may offer more utility to ship masters. The two main features any ship captain will look for are Waypoint record and Alert system capabilities.

1. Waypoint Mapping
GPS maps a series of waypoints along the way to the final destination. Calculation of a GPS waypoint from current position provides continuous update of a course to steer to the designated waypoint, the distance to the waypoint, and ratio of speed to time of travel. If off course, GPS indicates when a user should, “Turn”, “Steer” or alter navigation in response to an “Off-Course Error”. 

2. Alarm System 
Alarm features in GPS alert a user at time of arrival upon approach of a waypoint. The proximity alarm sounds off at a preset distance to a single or set of waypoints designated as part of the route to the destination. The anchor alarm signals passing of a preset distance marker from a waypoint, and the off-course alarm indicates when a ship has exceeded a preset distance from its intended course. 

Compatibility of GPS with other technologies has greatly improved since the introduction of the satellite mapping system and its software development. The existing capabilities of GPS to interface with new technologies designed to share navigation information about maritime operations (i.e. autopilot, plotter, or radar) adds value to the universality of the device. Sharing of information between GPS and other maritime operations systems applications enhances navigation intelligence. Data about a route allows a ship captain to monitor safety, as well as locate prime diving or port locations. Information about waypoints can be retained for future route planning. 

For information about marine navigation, contact a specialist in maritime operations for details about how you can benefit from a GPS satellite positioning systems.