Introduction

Activities towards next generation mobile communication are up to now technology driven. But, especially from an operator’s point of view, a system B3G has to deal with various aspects like user preferences, system requirements, network architecture, business model, security, and standardisation.
Mobile technologies are dominating the modern communication world. Third generation mobile systems are currently being rolled out. So far, most vision documents and discussions about B3G are focusing on wireless transmission technology issues. And in fact, generations were mainly characterized by the air interface in the past. But, the provisioning of mobile communication means more than just maintenance of the air interface. Various user expectations have to be met. Innovative services have to be developed to distinguish the operator’s offer from competitors. Complex value chains require reconsideration of business models and alliances. New technologies, especially in software technology, allow a more flexible reaction on changing market demands.

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Infrared is a special form of radio transmission in which a focused ray of light in the infrared frequency spectrum, measured in terahertz, or trillions of hertz (cycles per second), is modulated with information and sent from a transmitter to a receiver over a relatively short distance. Infrared radiation (IR) is the same technology used to control a TV set with a remote control. Unlike radio-frequency (RF) wireless links, IR wireless cannot pass through walls. It requires line of sight communication.
Infrared data communication is playing an important role in wireless data communication due to the popularity of laptop computers, personal digital assistants, digital cameras, mobile telephones, pagers, and other devices. Among existing uses or likely possibilities are:
• Sending a document from your notebook computer to a printer
• Exchanging business cards between handheld PCs
• Coordinating schedules and telephone books between your desktop and notebook computers
• Sending faxes from your notebook computer to a distant fax machine through a public telephone
• Digital cameras that can beam images into your computer.

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Ericsson initiated development of the Bluetooth technology in 1994, but today the specification is developed, published and promoted by the Bluetooth Special Interest Group (SIG) . Bluetooth wireless technology is a worldwide specification for a low-cost, low power consuming radio solution that provides links between different types of devices. It uses the globally available 2.4 GHz ISM (Industrial, Scientific and Medical) band.
As a provider of short-range connectivity, Bluetooth is initially replacing cables and proprietary wireless systems within existing applications. There are numerous applications in use today that benefit from Bluetooth technology, such as laptop-to-mobile handset connections, synchronisation between PCs and PDAs or smartphones, and headset-to-handset connections.

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A communication satellite function as an overhead wireless repeater station that provides a microwave communication link between two geographically remote sites. Due to its high altitude, satellite transmissions can cover a wide area over the surface of the earth. Each satellite is equipped with various “transponders” consisting of a transceiver and an antenna tuned to a certain part of the allocated spectrum. The incoming signal is amplified and then rebroadcast on a different frequency. Most satellites simply broadcast whatever they receive, and are often referred to as “bent pipes”. These were traditionally used to support applications such as TV broadcasts and voice telephony. In recent times, the use of satellites in packet data transmission has been on the rise. They are typically used in WAN networks where they provide backbone links to geographically dispersed LAN’s and MAN’s.

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The mobile and wireless communication technologies could play a significant role for the provision of value added services related to the cultural heritage and the fruition of tourist related navigation services. In reality wireless communications may be exploited through the provision of Location Based Services and complement the sattelite positioning systems for delivering innovative applications to the end users.

GSM
GSM (Global System for Mobile communication) is a digital mobile telephone system that is widely used in Europe and other parts of the world. GSM uses a variation of time division multiple access (TDMA) and is the most widely used of the three digital wireless telephone technologies (TDMA, GSM, and CDMA). GSM digitizes and compresses data, then sends it down a channel with two other streams of user data, each in its own time slot. It operates at either the 900 MHz or 1800 MHz frequency band.
While GSM provides excellent and well established voice services, its low transfer rates for data communications (up to 9600Kbps) make it inappropriate for LBS provisioning systems.

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Navigation Requirements

• Reliable Positioning System with Quality of Service
• Positioning Service with Integrity information about the displayed Position
• High coverage in Urban Environments
• Good Accuracy for both Horizontal and Vertical Positions
• “Wearable” GNSS receiver
• Connectable GNSS Receiver to other on person equipment
The following table summarises the main User Needs for the different Sector and Market segments. The most important parameters are related to the Integrity Concept and are highlighted in yellow.

Available Navigation Technologies

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 This new model uses objects to represent and organize spatial features.
 The geometry (spatial data) of a feature is stored as an attribute along with other attributes in a record.
 Objects can have properties and methods to capture characteristics of real-world objects.

 Object-based data model treats spatial data as objects.

 An object can represent any spatial feature: a road, a timber stand, or a hydrologic unit.

 An object can also represent a road layer or the coordinate system that the road layer is based on.

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Introduction
When you hear the term “cursor” what comes to mind? The symbol on a screen that shows where the next input activity will take place is the normal reaction. However, in ArcObjects, a cursor refers to a subset of records that is obtained by applying an attribute and/or spatial query on a feature class or table. This subset of records is held in memory rather than visually displayed. Do not confuse cursors with selections sets. Selection objects are used to display the currently selected features or rows in the ArcMap display, while cursors are not used for display purposes. For instance a search cursor could be used to programmatically generate a mailing list of all parcels of land within a 100 year floodplain and with a property value greater than $100,000. ArcObjects provides the ability to obtain cursors from geographic datasets (Feature Classes) as well as regular database tables. These cursor objects allow you to manage a subset of records in a single object. In this article we will explore the ArcObjects classes, methods, and properties used to manipulate cursors.

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• Is the center of GIS, most every processing in GIS we performed is a Geoprocesing.
• Definition (a GIS operation that takes one or more input datasets, performs one or more operations, returns one or more output layers (results))
o Four ways: dialog tool box, command line, model, script
o Model is a workflow chart that can execute multiple processes as one operation, share your idea with others
o Script, a text file contains instructions for geoprocessing of code, batch processing
• model builder
o interactive window used to create models inside of ArcGIS (data, connector, and tools)
• python script
o Every element in ArcMap is actually a ArcObject, ArcGIS is built with a set of ArcObjects
o Each ArcObject has properties and methods
o Python script based on the ArcObjects, through ArcObjects (COM objects) you can access geoprocessor (its peroperties and methods, or ArcObects’ peroperties and methods).

• Difference between 3D and 2D data
• 3D analyst include ArcScene and ArcGlobe, which used for visualizing 3D data, creating and analyzing 2D and 3D surfaces
• Type of 3D data
o 3D-surface (raster and TIN)
o 3D-feature (shapefile and geodatabase feature class), has a field of PointZ, PolygonZ, PolylineZ in the attribute table.
o Create TIN from vector data (point, lines, polygons)
o Mass points are nodes from which triangles are constructed
o Breakline: tell a distinct change; hard breakline capture abrupt changes in a surface, soft breakline do not affect the shape of the surface
o Replace, clip, erase, fill polygons
• Create 3D-feature
o convert 2D to 3D or
o define a new empty 3D feature then digitize from a 3D raster or TIN
• Convert TIN to features
o Slope and aspect polygon features, elevations of nodes as point feature
• ArcScene
o Scene properties: vertical exaggeration, animated rotation, background color, extent, and illumination (azimuth and sun elevation)
o Layer property: base heights (the z-value, could be elevation, population, precipitation, temperature, …) and extrusion (point to line, line to wall, polygon to block)