Wireless GIS - An Innovation in GISPriti Vangani priti_van@rediffmail.com Swetha Subramanian Smita Tripathy ABSTRACT: GIS is a powerful tool in decision making and managing processes in issues that are dealt with spatially related data. Wired systems cannot reach life and work demands appropriately, specifically when it is needed to access the system independent from time and location. So a new technology came to be known as Wireless GIS. It is the use of Internet and World Wide Web as a means of disseminating and processing geographic information. It provides users a capability to work interactively with maps and conduct spatial analysis on the Web. The languages XML and J2ME are being used to accelerate the development of the wireless GIS because, XML is an object based data format and developing the application in J2ME makes it platform independent. Applications thus developed enable one to have field access to geographic database from remote places and can update the database dynamically. Thus rendering GIS functionality the flexibility and making them more efficient. The wireless GIS is being applied in Field Mapping, Asset Inventories, Asset Maintenance, Online driving search, real time traffic information etc. INTRODUCTION: GIS as stands for Geographical Information System is a hardware, software and procedures designed to support the capture, management, manipulation, analysis, modeling and display of spatially referenced data for solving complex planning and management problems. As we see from definition GIS is a powerful tool in collecting and storing spatial information as well as nonspatial information .It helps in decision making as we can build queries using RDBMS in GIS. With the development of computers this storing of large quantities of data, maps and spatial information is possible. DISADVANTAGE OF WIRED GIS: Life and work encounter new challenges and problems. Therefore when the factors ‘Location and Time’ come, it seems to be a crucial. Location is fundamental to the way as we humans understand and operate in this world (Tang 2002). There are many demands today which need to be fulfilled independent of where we are at what time. With this ever increasing challenges in spatially- related managing and decision making applications, Wired GIS cannot meet the demands of users for easy access to spatial data and spatial analysis. WIRELESS GIS: Growing wireless capabilities create new horizons for serving nouvelle application through wireless network. Therefore advanced technology in GIS came into existence- Wireless GIS. It is considered as new sub-field in Geographic Information System. It is use of Internet and World Wide Web as a means of disseminating and processing geographic information. ADVANTAGES OF WIRELESS GIS: Wired GIS gives us static information about location. But there is significance in knowing when, how, how quickly one moves and the direction or route one takes. Delivery vehicles, emergency service patrols, weather fronts, buses, trains, taxies, wild animals, diseases- how fast they grow, where do they spread, being able to track them in real time is valuable. Most important need of wireless gis is when we are in move and need a location information- to be warned of traffic, accidents and congestion and giving driving instructions where to move, which is other optimum path to reach the destination so that one doesn’t waste his time first in searching about it while sitting on a desktop and delaying his journey. For asset service personnel, it provides information about faulty appliance whilst when they are in field rather than going to office and get information from map or desktop. Therefore the role of Wireless GIS is to capture location information on moving objects and events and to transfer this information to recipients in real time when they themselves are moving. Wireless GIS is considered to be a key contributor in providing services and contents and is a part of ‘mobile computing industry’ and must achieve standards to provide above facilities. COMPONENTS USED IN WIRELESS GIS: Wireless GIS is the integration of the following technologies:
The mobile communication industry is growing very fast resulting in development of wireless mobile communication. Whole world is connected to each other or we can say that this global connectivity is due to adoption of key communication protocols like GSM, CDMA (CODE DIVISION MULTIPLE ACCESS) Development of the internet has expanded the range of services to be provided to the users. The development of client-server technology helps to carry large spatial data on thin network. Mobile Communication Industry has adopted many standards such as XML and J2ME for client and web solution. Why XML and J2ME are used will be discussed later in this paper. GPS is the important component in mobile communication as it determines the location on the earth surface and keeps the track of the mobile phones in use and see that they are within the network. It is a kind of hand set based positional technology. Other handset based positional technologies are A-GPS, E-OTD. All the geographic information is manipulated, analyzed and presented through geographic tools used in spatial processing technologies. This spatial technology geocode the data, compress it and send it through thin network. There are many standards like WML and Mobile Location Protocol (MLP) that integrates these components. Work is still going on to improve the standards so that spatial data can be transmitted easily on wireless network without any error and congestion problems. LANGUAGES USED IN DEVELOPMENT OF WIRELESS GIS: Progress of Internet depends upon how one handles the data and information and mark-up languages. Mark-up language is a way of describing a document by placing tags in the document. Mark-up languages are different from other programming languages in certain conditional logics and subroutines. Different Mark-up languages are used in different applications. Some examples are XML, SGML, and HTML. SGML stands for Standard Generalized Mark-up Language. It is useful in handling large structured data but it is complex to use. HTML stands for Hypertext Markup language. It is a web based language which can embed texts, images and multimedia information in a single integrated format. HTML basically focuses on display of information rather than search, discovery and exchanges. Lack of information query and search functions is the major limitation of the HTML document especially for the geospatial data and maps. The languages used in the development of Wireless GIS are XML and J2ME. XML (Extensible Markup Language) is a standard for creating markup languages which describe the structure of data. It is not a fixed set of elements like HTML, but rather, it is like SGML (Standard Generalized Markup Language) in that it is a metalanguage, or a language for describing languages. XML enables authors to define their own tags. XML is a formal specification of the World Wide Web Consortium. (www.acad.bg/beginner/gnrt/appendix/glossary.html) Benefits of using XML-based data format, is that, it provides an object-based data format, in which each feature can be analyzed as an object or set of objects, independent from other features. Object-based formats make less time taking for communication and less transferred data amount. It is also flexible and comprehensible. Java 2, Micro Edition is a group of specifications and technologies that pertain to Java on small devices. The J2ME moniker covers a wide range of devices, from pagers and mobile telephones through set-top boxes and car navigation systems. The J2ME world is divided into configurations and profiles, specifications that describe a Java environment for a specific class of device. It can also be considered as version of Java used for developing applications that can run on a consumer wireless device platform (like a PDA or cell phone). (scmad.gayanb.com/j2me-glossary1.php) Developing in wireless Java (J2ME) provides flexibility to adapt many different platforms. Object-based data formats supply a spatially-suited data format. WIRELESS GIS ARCHITECTURE: The Wireless GIS architecture is a client-server model approach. The server side is responsible for listening the request and contains GIS server. GIS server consists of 3 elements:
A web based spatial interface is responsible to gather data from RDBMS and provide it to wireless clients. They enable integration of data from various users and provide tools so that data can be transferred and accessed easily in user environment.  Traditionally process of collecting data and collecting data is time consuming and error prone. Geographic data in the field is in form of paper maps. Any edits to be made in maps is made in the form sketches and notes. When back to the office, this edited data is entered manually in the GIS database. The result is that the GIS data is not as up-to-date as it could have been. Therefore Wireless GIS has enabled GIS to be taken into the field as digital maps in compact mobile computers- mobile phones, PDAs. Firefighters, police officers, engineering crews, surveyors, utility workers, soldiers, census workers, field biologists, and more use mobile GIS to complete the following tasks: Field Mapping, Asset Inventories. Asset Maintenance, Inspections, Incident reporting, GIS Analysis and Decision Making. The scope of location services is expanding rapidly. There are many users who require spatial processing only and not the graphical visualization or functionalities within the mobile units. An example of such services is emergency response basically to locate the mobile within a certain radius of area. Some providers use spatial information to offer search facilities by providing addresses to mobile that are not graphically enabled. Example- list of restaurants, banks, shops that are within the user’s present location. Many network providers tune their network range according to the user’s location to provide them better coverage and reliable services. And Wireless GIS help them to do it. Ability to track mobile users using this technology helps users to take care of their young ones and aged people. But tracking people and pets using this technology is basically exploiting this technology. Handheld PDAs with asset update systems are popular in asset maintenance department. The ability to download the location plans and asset details and to make amendments and updates while working in field has improved the efficiency. CONCLUSION: With development in the Wireless technology, a demand for using services from mobile is also increasing. This has led to the innovation of Wireless GIS. This paper exposes various features used by mobile computing industry to provide spatial services to GIS users. XML and J2ME are providing a powerful platform to help this technology to grow. The standards defined to support this technology have not been fully finalized. There are many drawbacks also of wireless technology that is small screen, less memory storage of mobile device. But due to great demand the field will grow in upcoming years. REFERNCES:
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