Syslog Technologies Innovative Thoughts

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1 Development and implementation of NMEA interpreter for real time GPS data logging Abstract: In Current Scenario GPS is very popular device among people for tracking and navigation purpose but GPS data can be used for several types of applications. This GPS data can be further used for analysis the trip, elevation profile etc. There are so many GPS data formats. Different GPS receivers support different formats. There are advantages and disadvantages of each GPS format. GPS provides many types information in various formats like binary, rinex etc. NMEA is one of them. In this work we develop a NMEA interpreter for logging GPS data which contains several types of information like Latitude, longitude, Time, Speed, Elevation etc. we develop this project in.net. NMEA is a combined electrical and data specification for communication between marine electronic devices such as echo sounder, sonars, anemometer, gyrocompass, autopilot, GPS rece ivers and many other types of instruments. The NMEA standard uses a simple ASCII, serial communications protocol that defines how data are transmitted in a "sentence" from one "talker" to multiple "listeners" at a time. Through the use of intermediate expanders, a talker can have a unidirectional conversation with a nearly unlimited number of listeners, and using multiplexers, multiple sensors can talk to a single computer port. Typical Baud rate 4800 Data bits 8 Parity None Stop bits 1 Handshake None

2 Introduction: The National Marine Electronics Association (NMEA) has developed a specification that defines the interface between various pieces of marine electronic equipment. The standard permits marine electronics to send information to computers and to other marine equipment. GPS receiver communication is defined within this specification. Most computer programs that provide real time position information understand and expect data to be in NMEA format. This data includes the complete PVT (position, velocity, time) solution computed by the GPS receiver. The idea of NMEA is to send a line of data called a sentence that is totally self -contained and independent from other sentences. There are standard sentences for each device category and there is also the ability to define proprietary sentences for use by the individual company. All of the standard sentences have a two letter prefix that defines the device that uses that sentence type. (For gps receivers the prefix is GP.) which is followed by a three letter sequence that defines the sentence contents. In addition NMEA permits hardware manufactures to define their own proprietary sentences for whatever purpose they see fit. All proprietary sentences begin with the letter P and are followed with 3 letters that identifies the manufacturer controlling that sentence. For example a Garmin sentence would start with PGRM and Magellan would begin with PMGN. Working principle: Navigation involves knowing where your boat is, knowing how to reach a destination, and ensuring that the boat does reach that destination. Historically, navigation-especially out of sight of land-required many skills. Given a starting point from dead reckoning (calculations based on speed,

3 time, and direction) or a sextant reading, you would track the boat's direction (with a compass) and speed (with a log) to continue to know the boat's position. Now, however, most mariners use a marine GPS chartplotter to navigate.the historical difficulties of being precise in every aspect of navigation resulted in many shipwrecks. With the modern GPS system, in which a receiver on your boat interprets signals from Global Positioning System (GPS) satellites, you can know your exact location to within a few feet. A marine chartplotter is a piece of electronic equipment that shows, or plots, the boat's position on a nautical chart, allowing you to see where you are in reference to hazards, points of land, and everything else on the chart. A plotter also runs software that allows you to easily accomplish other navigational tasks. In our project we will be developing an application in our PC which can get the information from GPS receiver and it will take out the required information from GPRMC statement and it will display the exact location, Date, Time and height from sea-level in different tabs. Using this information the sailor or the people in marine can estimate the things and they can continue their journey. Software used: C# Hardware Used: GPS Module. RS 232 converter. RS232 cable. TTL to RS232 converter board. Applications: Automotive security. Automobile tracking.

4 Marine Navigation. Advantage: Vehicle tracking can be done. Time will be noticed. We will get the exact location. Height from sea level can be calculated. Even Instant sped can be calculated. Disadvantage: Needs minimum of 3 satellites to give accurate value. Block Diagram:

5 Transformer Rectifier Power supply GPS MODULE Converter Max 232 RS232 Cable