A Basic Of GPS Technology

A Basic Of GPS Technology GPS Global Positioning Systems was a tool used by who has the need to navigate with the satellite through the microwave radio. Basically, GPS was use for route tracking in individual usage and it can use by different devices like pocket PC, forerunner and etc. But, nowadays a lot of organizations are using GPS technology to increase their business productivity like logistics company use GPS to keep track of the road in order to decrease the delivery time, travel agency or company use GPS to navigate the travel location and so on. The GPS is a rapid growth technology, which provides enhance flexibility and accuracy of positioning tracking for surveying, navigation and GIS data capture. It can divide by front end and back end usage in users segment site in a set of business GPS system. Front end consist navigation and back end include GIS data capture and surveying. GPS was a satellites based system which is space-based navigation system. By communication with the satellites, GPS require 3 parts of segments that are space segment, control segment and user segment. The GPS satellites act as a references point from orbit to ground detect the receivers position. By detecting the position, GPS satellites able to receive the data from counting the longitude and latitude of the receivers; then send back the require data to receivers in order to let the pointer move on map files. The map file is a file with extension (.img) which is like image file from our Windows. This map file only available in navigation devices like pocket PC and GPS navigators; GIS data capture was using different method to manipulate the GPS technology and different infrastructure. The famous GPS navigation device manufacturers and services provider are Garmin and Tom Tom. They are using government satellites and only allow accessing the satellites for navigation purpose. 1.2 The History of GPS Technology The first GPS satellite was available in United Stated government which is for military usage in Air Force in early 1978 called NAVSTAR (Navigation System with Timing and Ranging), now we called as GPS. At the same time, U.S. DoD (Department of Defense) has launched 11 satellites in orbit. In the year of 1979, U.S. DoD decided to expand the satellites system which is increase the quantity of the satellites in orbit from 11 to 18 and at the next year, which is year of 1980, the GPS atomic clocks onboard satellites has activated by using these 18 GPS satellites. GPS satellites are not only implemented by U.S. At the year of 1982, Russian Federation Ministry of Defense has launched a first GPS satellite for their country; it is called GLONASS (GLObal NAvigation Satellite System). Quantity of GPS satellites also has increased from 18 to 24 in year of 1988 because 18 satellites were not satisfying the requirements from these countries. In year of 2000, GPS technology growing into consumer and industry usage, it is no longer is the patent for military purposes which mean it allow use in individual and business. 50th GPS satellites have been launched on year of 2004, purposely to help to meet the requirements from the civil, industry and military. Year 2005, a special GPS satellite launched in order to support the new military M-signal and the second civil signal L2C called IIR-M GPS satellite. This satellite developed by Lockheed-Martin, this type of satellite can help to increase the power of signal to receivers on the land, improve the security with enhanced encryption method and also included anti- jamming capabilities for military. CHAPTER 2: FUNDAMENTAL OF GPS TECHNOLOGY 2.1 GPS Segments The GPS technology was established by 3 segments or as known as GPS system segmentation which are space segment, control segment and user segment. They are performing different tasks and send or receive different kinds of signal to each other when GPS is performing the tasks. 2.1.1 Space Segment The space segments major component is GPS satellites. The space segment currently has 28 satellites orbiting the earth on 6 different orbital planes. The satellites orbit altitude was selected so that the satellites only repeat the same orbit track over any point on earth on 24 hours which mean each satellites has its own track, they will not spend on others track. The distance between earth surface and satellites are approximately 20,200 kilometers and satellites travel at about 12,000 kilometers per hour rounding the earth. Every satellite was using solar power with a backup battery and it contains a microwave radio transmitter and receiver, and one or more atomic clocks and small thrusters using for course correction and special antennas. The special antenna on the GPS satellites are designed for allow GPS data signals to be send and receive anywhere from the earth surface with distance approximately 5,000 kilometers into space. This service not only meets the individual usage req uirement, it is also providing the military needs which satellite tracking and missile guidance capabilities. 2.1.2 Control Segment The control segment is a satellite station which is operated by U.S. military. There are 5 satellites station in the world but 4 are unmanned satellite stations. These 4 unmanned satellites station are established at Hawaii (Pacific), Ascension (Atlantic), Diego Garcia (Indian) and Kwajalein (Pacific). They are used for receive and send data to or from satellites and trace the actual position of the satellites. Then, the information from 4 unmanned satellites station is periodically send to master station which is in Colorado Spring (U.S.), master station will combine the information and establishes correction factors. This information was used for update atomic clocks on satellites if necessary and also can use to adjust the thruster position in orbits and maintain them in the proper slot. 2.1.3 User Segment The user segment is related with the all the GPS receiver users and GPS satellites signal. It is very important to track the position of the GPS users. User segment transmit GPS signal with satellites as synchronizing; if each of them lost the signal connection, satellites will not able to track the GPS users position. GPS satellites can transmit the data with unlimited GPS receivers at any one time and providing stable connectivity with all the users. The user segment served by many commercial industries whose like GPS device manufacturers and resellers are selling GPS hardware, application and service. Anyone selling GPS devices are not requiring license, fees and restriction to access to satellites. 2.2 Data Format and Hardware Interface In order to let GPS receivers function properly, it requires different signals from GPS satellites. These signals are broadcasted by satellites after time and position are determined and calculated. To ensure the GPS receivers and satellites can working properly by each others, manufacturer will provide defined data format and protocol (proprietary) or using international standard data format (NMEA). 2.2.1 Data Format Data Format had divided by 2 types which are proprietary and NMEA data format. In this section, it will state the details of both data format for GPS technology. Proprietary Data Format Propriety data format was a data format formatted and defined by manufacturer itself. Most manufacturers define their own data sets and control command in GPS receivers. For example, data require by receivers from GPS satellites will be formatted to proprietary format to working to their own brand receivers such as height, speed, status, position and etc. all can be communicated. Different manufacturer or receivers brand has different propriety data format because each manufacturer has develop their own data format. NMEA Data Format NMEA Data Format was controlled and created by U.S. based National Marine Electronics Association. It used for ensure data exchange take places without any issues and problems by standardized the data format. NMEA was a combination of the electrical and data specification use for communication between GPS receivers. NMEA used a simple protocol to define how a data transmitted to a message from a GPS satellite to many GPS receivers which means data sent by GPS satellites will be translate to NMEA in order to let GPS receivers to understand. 2.2.2 Hardware Interfaces Antenna Antenna absolutely used for receive GPS signal from satellites. Antenna for GPS receivers are 2 types available in our market, they are Patch antenna and Helix antenna. Patch antenna is a flat and usually has a metalized and ceramic body which amounted on a metal base plate. Helix antennae has a cylindrical helical and mounted on a ground plane. Compared with patch antenna, helix antenna had high gain signal and stable. To ensure patch antenna has high degree selectivity by GPS receivers manufacturers, the base to patch surface ratio has been modified and adjusted to meet the smaller GPS receivers requirements. Supply Supply in GPS receivers are used for supply power to GPS receivers. Basically, receivers must be powered an external voltage source about 3.3 Volts to 6.0 Volts. Time Pulse Time pulse used for GPS receivers to generate time pulse in every second. Most of the time format will be synchronize to UTC (Universal Time Coordinated) time format by time pulse. Time format before synchronize generate to UTC format are TAI (Atomic Time), GPS Time, Satellite Time and Local Time. 2.2.3 Receivers Module GPS receivers must measure the weak signals from at least 4 GPS satellites which in order to ensure can determine and calculate the position and time correctly in 3D (three dimension) position. Time signal was often emitted with latitude, longitude, height and synchronized with UTC. When determine and calculate the time and position, other variables like speed and acceleration also calculated at the same time. The signal received from satellites are about 1575.42 MHz, the signal are pre-amplified and transform to a low intermediate frequency. After that, the low intermediate frequency signal will be converting into digital signal (2 bits). By converting the signal to 2 bits digital signal, receivers can understand the data send by GPS satellites and able to calculate the require variables and display the final output for the users. 2.3 GPS Devices A GPS device was a device that receive GPS signal to determine the location or position on the earth. Nowadays, a lot of different type GPS devices are available in the market like GPS navigator and etc. In this section, I am going to discuss the consumer products in our market. 2.3.1 GPS Navigator GPS navigators are specially designed for position tracking and they are portable. GPS navigators have a flat screen and provide touch screen feature, the screen normally are 3.0 inch to 6.0 inch. In order to let consumers has an up-to-date map image, manufacturers are using image file to represent the map. It had a graphical map to provide a good user interface to ease to use to the users. When the consumers request to update their map image, reseller or retailer just copy the latest image file to the GPS navigator and replace the old map image file. 2.3.2 Pocket PC Pocket PC as known as mobile, PDA or smart phone. It is not specially designed for tracking the position. Because of the competition on the market, mobile manufacturers add on a lot of features into their products in order to attract more consumers and increase the sales. GPS function is one of the add on feature. Nowadays, GPS manufacturers have provide different platform GPS software to meet the market requirement. For mobile, platform can be divided by 3 major platforms which are Windows, Android, Symbian and iOS. Same as GPS navigator, mobile GPS has a graphical map and also structured by image file. It provide ease to maintain and easy to install by mobile resellers and retailers. 2.3.3 Forerunner The GPS Forerunner was a sport watch and made GPS navigator manufacturers such as Garmin and Tom Tom. The purpose of the production of the forerunner is targeted to triathletes and road runners. The forerunners are designed as a device that can accurate to measuring the speed, altitude, distance, pace and time, all of these are important to an athlete in training for races. By using forerunner, athletes can know their running speed, distance between starting point and end point, time to complete the training and so on. It can help them to improve their running speed by seeing physical result and using forerunner. CHAPTER 3: THE USE OF GPS TECHNOLOGY 3.1 GPS Applications Since the GPS technology became more and more advanced and ideal, GPS has been used in variety of the applications for real-time in-vehicle tracking. These are included probe vehicle surveillance, congestion management, fleet management, travel diary surveys and GPS and map matching. 3.1.1 GPS Applications in Probe Vehicle Surveillance Transportation experts have been explore use of the floating car technique to obtain cars travel time information since 1920s but it is done by manually by human which is driver record all the require information themselves. Human errors are always became the major problem for data incorrect issues. As computer technology improved, this manual method has replaced by DMI (Distance Measuring Instrument) which determine the distance and speed by pulses from a sensor to vehicles. It also generated a problem which overwhelming data file sent by sensor caused the computers storage problem. GPS technology has overcome the disk storage and data error problems since GPS able to work with GIS (Geographical Information Systems), it provide automatic geo-coding of positioning and speed data. This feature can let the transportation experts see the vehicle travel information on the spot from GIS. Data require can be analyzed by GIS sent by GPS which GPS become a front end which perform sending data to back end which GIS. Analyzed data will store in to a database and generated as a report, it could be largely reduce the human input error and overcome overwhelming file causing the disk storage problem. 3.1.2 GPS Applications in Congestion Management The traffic congestion will beyond the personal inconveniences felt by individual travelers. Roadway safety and environment quality are factors arise the congestion. A CMS (Congestion Management System) is a decision support system using for choosing strategies and alternatives to have a better relieve traffic congestion. CMS using GPS-GIS approach for collecting require congestion data. GPS used for collecting data and GIS used for display information like traffic corridor. The analyzed data can used by congestion management in order to calculate and determine traveler delay, vehicle emissions, idling time and wasted fuel. 3.1.3 GPS Applications in Fleet Management GPS technology can used for translate fleet location data into real-time reporting. When combined all the technologies used by management, it can help to provide a services solution for all sizes of fleets like fleet maintenance and cost-effective tracking. GPS can help fleet management to improve efficiency by real time vehicle status and location reports or routes and driving history collection. This information can help trucking organizations assess delivery performance to improve the route plan, fleets scheduling and dispatching capabilities. Government services fleets such as fire trucks, ambulances and police cars also using GPS for route guidance of the nearest vehicle that has face the incident. 3.1.4 GPS Applications in Travel Surveys Travel survey basically done by government; objective of the travel survey was they need to understand peoples travel behavior in order to more easy to maintain traffic order and national road construction. The purpose of using GPS technology in travel surveys is to supplement or replace form of travel survey collection by interview and forms filled by interviewees. GPS was advantageous in reducing respondents burden, improving data quality, collecting additional information and the survey period can be extended to everyday. Traditional way to implement survey is conducted using paper and pencil interview, sometime it can be increase respondents burden and information given are not correct. GPS can provide detailed and analyzed information about trip and travel behavior. By accessing GPS satellites, government can retrieve the information easily; it can help them more easily to achieve their targets. 3.1.5 GPS Applications and Map Matching Map matching is more focus on algorithm and alternative to using point-to-point distance estimation. Because of different tracking system developers has develop different types of tracking systems, the algorithm used and alternative to estimate the distance are different such as voice based tracking system does not consist graphical interface, may using voice and sound to tracking the route or vehicle from back end station. GPS applications used in map matching was using different algorithm; it has graphical interface and back end station able to track the vehicle on the spot. The algorithm of GPS applications to matching map has 3 major steps which are smoothing procedure by removing anomalies from the raw GPS data, identified the vehicle taken en-route and the actual matching of point to the GPS network. Algorithm was standardized, it help the developers more easy to implement a tracking system with better performance and trusted or reliable. 3.2 Reasons to Consider GPS in Business Applications 3.2.1 Automation of Many Record Keeping Functions By using GPS, information related with track or vehicle can automate schedule to store and retrieve without human interaction. Vehicle can be auto tracking by GPS system such as track the services location, routes used and equipment drop off points. And then, it is also able to recording down employees (delivery person, driver and etc.) hours of work and vehicle automatically. 3.2.2 Improved Operations GPS providing real time tracking on vehicle; if any incidents happening on vehicle drivers, managers can understand the vehicle status or location in order to make decision to solve the incidents immediately. Therefore, GPS enable real time decision making for the organizations which are using GPS systems. 3.2.3 Decreased Wear and Tear Means controlling the speed of the vehicle can prevent excessive of tires and engine wear because of vehicle are tracking by back end station to eliminate the drivers furious driving. By tracking vehicles, it can also help an organization to eliminate of unauthorized use of company vehicle in order to reduce overall vehicle mileage. 3.2.4 Better Use of Company Resources By using GPS system to tracking vehicles, it can help an organization to identify and eliminate of unauthorized use of company vehicle in order to reduce fuel wasted. Active management of vehicles enables fact based decisions to save the time and human power to analyzing the virtual information to making a decision. 3.2.5 Efficient Route Management and Dispatching Support GPS systems able to find a shortest route to reduce the delivery time, calculate the time arriving in the locations based on the distance and speed driving in order to let the drivers know when he will arrive and how long the distance he should travel. Management also able be aware of the driving direction by tracking the vehicles in order to prevent service delay. 3.2.6 Faster Response Time GPS provide automation of keeping record of vehicle status, driver travel behavior in order to improve driver efficiency. GPs also can guide the drivers to go to their services by using GPS navigator which helping them to prevent lost on road. 3.2.7 Reduced Liability and Insurance Costs By using advanced GPS system, the chances for the accidents also can be reduced because drivers driving speed was tracking by GIS which is used in back end. Therefore, most of the insurance companies are more likely giving discount for those who using the GPS systems and insured paid also can be reduced. Tracking system always keeping record automated, it can help company to avoid the false claims by drivers with tracking data in the database. 3.2.8 Employee Safety Drivers travel behavior was tracking by GPS system and it store into database as information. By tracking, it can help keep drivers to maintain well situated speed and focused on safe driving. Company also can be reward for those safe drivers based on the information tracked to improve their faith on safe driving. CHAPTER 4: INTEGRATION OF GPS WITH BUSINESS APPLICATIONS 4.1 GPS Comparative Systems in Business Nowadays, GPS has integrated with business applications and it has different types of systems. A differentiation between those systems on the market are how they communicate with the office, where the information should stored for analyzing process and how they handle driving history or vehicles information. Different type of the systems has different type information handling process. Today, comparative systems have divided by 3 types; they are passive (stored data) system, active (real-time) system and hybrid (combined) system. 4.1.1 Passive (Stored Data) System By using passive system, it requires an onboard recording device to store GPS signal data during vehicles travel time. Information stored on the onboard device is used for upload and retrieval to the office computers after vehicles return back to the home base. Alternatively, data stored on the onboard device also can be transfer to removable storage modules. It can send to the office computers by email when the people are away from the office. Strengths Provide solution for those vehicles that do not return to the home base every day. Saving costs for communication between companies computers and vehicles. Saving computers storage while office staff can select the information which files they want to retrieve and store in the computers. Limitations May require additional removable data storage module to retrieval the vehicles information. Not provide real time tracking process, information may not up-to-date and obsolete. Status of on travel vehicles are not well known immediately, slower response time when facing incident. 4.1.2 Active (Real-Time) System Active system relying on GPS receiver mounted on the companies vehicles. And, it also requires a wireless data communication conduit like cellular data line built into a device. Real time of GPS signal data such as speed driving, longitude, latitude and driving direction will be transmitted over the wireless cellular data line to data collection point in a set of interval. Data collection can point be companies office or GPS tracking system service providers website. These information can be transmit as directly to the vehicles home base or Internet site which GPS tracking system service providers, the subscribing companies can view its vehicles activity on the webpage. Strengths Allow office staff to keep track of vehicle activity real time without contact with the drivers. Facilitates to make emergent adjustments for special situations like vehicles damaged in accidents, management can assign another vehicles to complete the tasks. Limitations May require manpower to observe the vehicles activity updates throughout the whole working day. Cost of the data transmit could be very high due to the cellular data line. Information stored on the service providers only available for a shorten time, causing difficult for long term analyzing. 4.1.3 Hybird (Combined) System Combination of passive system and active system, it providing real time vehicles tracking feature and the information tracked can stored in the computers for long term analyzing or permanently. Hybird system required all the components, devices and equipments used in passive system and active system. Real time data will be transmitted to the data storage over the network immediately, information in computers database are synchronized with real time GPS data. It is not required user interaction during information retrieve and store progress. Strengths Information stored are completed and updated, companies management ease to access the fresh data anytime. Interruption of the communication would not affect the information lost since onboard device also perform jobs to store the vehicles travel information. No user interaction required, save the labor cost to observe the vehicles activity updates throughout the whole working day. Limitations More expensive compared others system which required all the components from passive system and active system. Computers storage unit easily full and wasting the storage due with the real time store procedures and save as permanently. 4.2 GPS Business Information System Components Most of the GPS Business Information Systems are combined from different sub-system or components. Generally, these components are perform different tasks in order to let whole the system became more perfection. These components working in different areas like back end, front end and etc. 4.2.1 GPS Units / AVL (Automated Vehicle Location) GPS units were onboard vehicle devices and it using AVL technology in GPS business information systems. AVL was a vehicle tracking system. For vehicles, real-time positioning for each vehicle was tracked and measured by AVL. Basically, vehicles travel history and activity information is temporary stored in vehicles for a short time, which means time for information stored in the vehicles can be as short as a few seconds or as long as several minutes. This information will transform into a raw form or processed on-board in vehicles before its transmission to the control center usually called back end. AVL used in onboard vehicles which included GPS units such as GPS navigator, removable storage module and satellites signal receiver module. AVL can trace the vehicles location and position over the signal receiver module. Then, manipulate the data into a raw form either store in removable storage module or control center. 4.2.2 Data Processing and Server / GIS (Geographical Information Systems) GPS system using GIS engine in server to manipulate the information collected from AVL. GIS can be display the information in graphical form in order to let the user interface became more interested and easy to understand by end users. Information collected from AVL usually stored in the server, server can stored more information and more powerful to perform the heavy tasks like DBMS (Database Management System) processing. In server, GIS are performing historical data generation which is related with standard RDBMS (Relational Database Management System) like using Oracle or SQL and also crystal reporting. The major to using GIS engine was end user usually require a graphical map in order to let them know the activity of the vehicles on road more clearly, provide user friendly to the end users and information analyzed are accurate. Data processing and server usually happening in control center or back end office specialized for management. 4.2.3 Communications / Network Communications are a middleman between GPS units and data processing and server. Communications can have many types such as GSMSMS, GSMGPRS, iDEN, TETRA, Satellites, and Wireless download. The purpose for using communications is transfer the information from GPS units to server. Different data processing and server system architecture require different kinds of network. Different communication protocols and network also can be used simultaneously, it depend on budget of the companies and see either how the developers going to design for the system. Communication usually needs to subscribe from third parties communication companies like in Malaysia have TM, the monthly services fee should be paid by the organization and the amount can be large depending on the system modules or its infrastructure. Therefore, communication fees became routine payment after developing system. 4.3 Types of Business Industry Using GPS Technology Nowadays, GPS technology became more and more popular in business usages. It integrated with others system in order to improve business process, increase business productivity and etc. Different business industry using different GPS technology, harvest from using GPS also will be different. In this section, I am going to discuss GPS technology used by different business industry; they are agriculture, forestry and tourism. 4.3.1 Agriculture In agriculture industry, they are used GPS in site-specific farming or precision agriculture and it is combining GPS and GIS technology. The technologies used can help farmers to enabling coupling of real time data capturing with analyze of large amounts of geography information, accuracy of positioning data capture and leading to the efficiency manipulation. The GPS applications in precision farming are farm planning, tractor guidance, filed mapping, crop scouting, soil sampling and yield mapping. The major reason for precision farming was collecting timely geography data on prescribes or requirements of plants, soil and animals to increase their production in farming and protect their environment. The approaches stated above are relying in integration of computer based system, GPS positioning and time and data collection sensor. Through using GPS in farming, information for improve the soil and water can be improved for plants growth. Farmers can obtain extra benefits from soil amendments and fertilizers such as quality and quantity increased for the harvest by soil improvement. Moreover, crop advisors also used GPS with rugged data collection tools for accurate position to insect, pest and weed injury in the farming field. The areas which affected by pest will mapped and pinpointed for future decisions make by management. It used to solve the pest problems by using minimal chemicals to protect the crops and land soil. Minimal chemicals used not only helping them to protect their crops and land soil, it is also helping them to saving the cost used to purchase chemicals, reduce environmental pollution and public nuisances. 4.3.2 Forestry GPS technology used in forestry industry area was called as precision forestry. The GPS forestry system was aimed to the accuracy of GPS data collected from forest vehicles machine like forest trucks in different level of forest to increase the organizations forest vehicle machine performance and reduce to costs wasted in vehicle machines. GPS is being used for managing forest and timberland resources. If using a mobile forest harvesting machine, data collected from GPS able to improve design of the forest engineering and decisions of the management based on forest vehicle machine performance information as function of timber stand and terrain variables. The technologies are combining GPS and GIS to ensure the data collected can be more efficiency for organization operations use. The GPS applications in forestry industry are locating of sample plots in forest stands, navigating for aerial surveys and updating forest maps. To locating of sample plots in forest, GPS receiver is using fo