Symbian3/SDK/Source/GUID-BA49FDC0-808B-5E05-81AC-98637214F304.dita
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+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->
+<!-- This component and the accompanying materials are made available under the terms of the License 
+"Eclipse Public License v1.0" which accompanies this distribution, 
+and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->
+<!-- Initial Contributors:
+    Nokia Corporation - initial contribution.
+Contributors: 
+-->
+<!DOCTYPE concept
+  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept id="GUID-BA49FDC0-808B-5E05-81AC-98637214F304" xml:lang="en"><title>LBS
+Quick Start</title><shortdesc>Location Based Services (LBS) provides location information for
+installed applications and for remote services via a network. Location information
+can be used for location stamping artefacts such as photographs and memos,
+finding nearby services and facilities, navigation, and the ability for remote
+parties to discover the user's whereabouts. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
+<p>Location-based services (LBS) use coordinates from the World Geodetic System
+(WGS 84), which is also used as a reference system by the Global Positioning
+System (GPS). </p>
+<p>The coordinates are based on values for latitude, longitude, and altitude
+(elevation above sea level). </p>
+<p>The North Pole is 90 degrees North (+90 degrees) and the South Pole is
+90 degrees South (-90 degrees). The Equator is defined as 0 degrees; locations
+above it have positive latitudes (0 to +90 degrees); those below (0 to -90
+degrees) negative ones.</p>
+<p>There are two definitions of North Pole; Magnetic North Pole and True (Geographical)
+North Pole. Any application with a compass must check how the API defines
+North Pole.</p>
+<p>The Magnetic North Pole is the point to which compasses point. The True
+North Pole defines latitude as +90 degrees. </p>
+<p>Meridians are constant longitudinal (north-south) values. The Prime (Greenwich)
+Meridian’s value is 0 degrees. WGS84, which LBS use, defines its zero meridian
+some 100 meters east of the Prime one. Locations east of the Prime Meridian
+have positive longitudinal values (0 to +180 degrees), those west (0 to -180
+degrees) have negative ones. </p>
+<p>As seen in the figure below, latitude lines are smaller near the poles.
+At the equator, one degree of longitude is roughly 111.3 km, whereas at 60
+degrees of latitude one degree of longitude is only 55.8 km, which is more
+difficult to see.</p>
+<fig id="GUID-D98458F6-8EBD-43B9-9C3C-5204BD837D2D">
+<image href="GUID-0C01305E-9E73-4E44-BD13-361C93CC5E79_d0e240538_href.png" placement="inline"/>
+</fig>
+<section id="GUID-D4201DF5-26DD-5E46-B228-A3CAA467C7C6"><title>Getting started
+with LBS</title> <p>This section provides links to the most important documentation.</p> <p><b>For
+application developers</b> </p> <p>The <xref href="GUID-D0318BB6-0B9F-5A1C-AB0B-61BA22D28661.dita">Location
+Acquisition API</xref> is the interface that programmers use to create location-aware
+applications. The API gives developers the ability to get location fixes and
+to obtain information about the positioning technologies available to the
+mobile device. </p>      </section>
+
+<section id="GUID-CA5D2674-B469-44D8-9255-1F35CA7B8D41"><title>Technologies</title> <p>The
+main technologies enabled on the Symbian platform by the LBS subsystem are
+as follows: </p> <ul>
+<li id="GUID-62F84865-11D4-50BA-A139-7EEA7232BC8F"><p>Global Positioning System
+(GPS) </p> <p>The GPS system provides accurate, worldwide positioning. The
+main disadvantage of GPS is the long time required to obtain a position fix
+when the GPS hardware is first powered. LBS supports Assisted GPS (A-GPS)
+to reduce the time required to get a position fix. </p> </li>
+<li id="GUID-64669486-6B59-5AE4-A337-E9E50C3C3F1E"><p>Network based positioning </p> <p>Network
+based positioning is typically less accurate than GPS, but often provides
+a faster fix of adequate accuracy for some applications. </p> </li>
+<li id="GUID-05A9FF0E-A974-5CD7-A854-784CB23AA2A4"><p>Secure User Plane Location
+(SUPL) v1.0 </p> <p>SUPL defines an architecture for supporting Location Based
+Services using IP bearers to connect handsets and network hosts. The Symbian
+LBS subsystem contains a SUPL Protocol Module to support SUPL. </p> </li>
+</ul><fig id="GUID-52D81395-87C4-4706-97E5-84336EA53C69">
+<image href="GUID-0CCCF088-E636-4C12-AA5E-3E2CB04424AD_d0e240595_href.png" placement="inline"/>
+</fig><p>The above figure illustrates how the location information can be
+provided to the device. Access to these location methods is provided through
+the positioning modules.</p> </section>
+</conbody></concept>
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