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	<title>Home &#187; Mobile</title>
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		<title>iPad Release Pricing &#8211; Australia not Screwed</title>
		<link>http://www.timdavis.com.au/internet/ipad-release-pricing-australia-not-screwed/?utm_source=rss&#038;utm_medium=rss&#038;utm_campaign=ipad-release-pricing-australia-not-screwed</link>
		<comments>http://www.timdavis.com.au/internet/ipad-release-pricing-australia-not-screwed/#comments</comments>
		<pubDate>Sun, 09 May 2010 06:53:15 +0000</pubDate>
		<dc:creator>Tim</dc:creator>
				<category><![CDATA[Internet]]></category>
		<category><![CDATA[Mobile]]></category>

		<guid isPermaLink="false">http://www.timdavis.com.au/?p=1285</guid>
		<description><![CDATA[<div class="addthis_toolbox addthis_default_style " addthis:url='http://www.timdavis.com.au/internet/ipad-release-pricing-australia-not-screwed/' addthis:title='iPad Release Pricing &#8211; Australia not Screwed '  ><a class="addthis_button_facebook_like" fb:like:layout="button_count"></a><a class="addthis_button_tweet"></a><a class="addthis_counter addthis_pill_style"></a></div>Yes, it&#8217;s true &#8211; Apple have finally released the pricing details for Australia in relation to the coveted iPad and I almost fell over when I read them. The most amazing part &#8211; Australia hasn&#8217;t been insanely ripped off in relation to the pricing which is a great thing considering most of Apple&#8217;s product are overtly expensive. [...]]]></description>
			<content:encoded><![CDATA[<div class="addthis_toolbox addthis_default_style " addthis:url='http://www.timdavis.com.au/internet/ipad-release-pricing-australia-not-screwed/' addthis:title='iPad Release Pricing &#8211; Australia not Screwed '  ><a class="addthis_button_facebook_like" fb:like:layout="button_count"></a><a class="addthis_button_tweet"></a><a class="addthis_counter addthis_pill_style"></a></div><p><img class="colorbox-1285"  src="http://www.timdavis.com.au/wp-content/uploads/2007/10/tim_davis.jpg" alt="Tim Davis" hspace="15" vspace="5" align="right" />Yes, it&#8217;s true &#8211; Apple have finally released the pricing details for Australia in relation to the coveted <a title="iPad" href="http://www.apple.com/au/ipad/" target="_blank">iPad</a> and I almost fell over when I read them. The most amazing part &#8211; Australia hasn&#8217;t been insanely ripped off in relation to the pricing which is a great thing considering most of Apple&#8217;s product are overtly expensive. The pricing is basically identical to that of USA when incorporating the conversion rate and GST. As <a title="iPad" href="http://www.apple.com/au/pr/library/2010/05/07ipad.html" target="_blank">Apple&#8217;s Official Press Release</a> states, the iPad pricing for Australia is:</p>
<p>Wifi Only</p>
<ul>
<li>$629 &#8211; 16GB [$499 USD at <a title="Exchange Rate" href="http://www.xe.com/ucc/convert.cgi?Amount=499&amp;From=USD&amp;To=AUD" target="_blank">Exchange Rate of $0.88</a> - $560 + 10% GST [$56]= $616 which isn&#8217;t too bad at all]</li>
<li>$759 &#8211; 32GB</li>
<li>$879 &#8211; 64GB</li>
</ul>
<p>3G Pricing</p>
<ul>
<li>$799 &#8211; 16GB</li>
<li>$928 &#8211; 32GB</li>
<li>$1049 &#8211; 64GB</li>
</ul>
<p>Given that Apple usually increases Australian prices by around 30% in comparison to our USA counterparts &#8211; despite any associated exchange rate differences &#8211; I was expecting the iPad to be priced around $700 &#8211; $750 AUD range. Evidently, I think that would have priced too many people out of the market for the iPad and many Australian&#8217;s would question whether this is within the permissible range of their budget or whether it&#8217;s simply more economically efficient to go and purchase a new computer. Granted, the iPad is a &#8216;cool&#8217; multi-functional device but the more expensive models are the ones that really have the best functionality in terms of 3G connectivity.</p>
<p>Would I buy one ? No. That&#8217;s primarily because I already have an iPhone and this is more than useful enough in terms of reading web-pages. Adding this to the existing PC and iMac &#8211; I just don&#8217;t see when or where I would use something like an iPad. The use case that it presents for me at the moment does not scale up the utility curve that much. That&#8217;s not to say that it wouldn&#8217;t be a great device to use for reading or watching movies while chilling out on the couch. My old chunky laptop is fine and dandy for checking the web [that's cool enough for me though] and the sleekness of the iPad evidently is more comfortable to hold &amp; move around &#8211; but I&#8217;m just not willing to fork out $630 AUD when the <a title="iPhone HD" href="http://gizmodo.com/5520164/this-is-apples-next-iphone" target="_blank">new iPhone is being released soon</a> and the feature set included in this will more than compensate.</p>
<p>I guess if I was asked the question &#8211; new iPad or new iPhone? [and budgetary constraints only allow me to choose one] &#8211; well, the later wins by a mile over the former &#8211; simply because the utility of the later is so much greater than the former. In my mind, it has been a little unfortunate for Apple since had the iPad been released earlier and not when it&#8217;s about to overlap a pending product release [the new iPhone expected in June] &#8211; then it might have been a better proposition to many people. For me, a new iPhone is a much greater value proposition than a new iPad and better yet &#8211; companies like Virgin Mobile basically subsidize the phone over a 12 or 24 month period.</p>
<p>So while I welcome the iPad, I await for the next iPhone.</p>
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		<title>Are Location Based Services the Way of the Future?</title>
		<link>http://www.timdavis.com.au/mobile/location-based-services-the-way-of-the-future/?utm_source=rss&#038;utm_medium=rss&#038;utm_campaign=location-based-services-the-way-of-the-future</link>
		<comments>http://www.timdavis.com.au/mobile/location-based-services-the-way-of-the-future/#comments</comments>
		<pubDate>Wed, 18 Jun 2008 04:13:40 +0000</pubDate>
		<dc:creator>Tim</dc:creator>
				<category><![CDATA[Mobile]]></category>
		<category><![CDATA[GPS]]></category>
		<category><![CDATA[LBS]]></category>
		<category><![CDATA[location]]></category>

		<guid isPermaLink="false">http://www.timdavis.com.au/2008/06/18/location-based-services-the-way-of-the-future/</guid>
		<description><![CDATA[<div class="addthis_toolbox addthis_default_style " addthis:url='http://www.timdavis.com.au/mobile/location-based-services-the-way-of-the-future/' addthis:title='Are Location Based Services the Way of the Future? '  ><a class="addthis_button_facebook_like" fb:like:layout="button_count"></a><a class="addthis_button_tweet"></a><a class="addthis_counter addthis_pill_style"></a></div>There has been so much coverage in the Media regarding Location Based Services (LBS) and how they are the way of the future. While I tend to agree with the vast majority of what&#8217;s being said out there at the moment – I thought I would do a bit of exploration around how location based [...]]]></description>
			<content:encoded><![CDATA[<div class="addthis_toolbox addthis_default_style " addthis:url='http://www.timdavis.com.au/mobile/location-based-services-the-way-of-the-future/' addthis:title='Are Location Based Services the Way of the Future? '  ><a class="addthis_button_facebook_like" fb:like:layout="button_count"></a><a class="addthis_button_tweet"></a><a class="addthis_counter addthis_pill_style"></a></div><p><img class="colorbox-12"  src="http://www.timdavis.com.au/wp-content/uploads/2007/10/tim_head.jpg" alt="Me" hspace="15" vspace="5" align="right" /></p>
<p>There has been so much coverage in the Media regarding Location Based Services (LBS) and how they are the way of the future. While I tend to agree with the vast majority of what&#8217;s being said out there at the moment – I thought I would do a bit of exploration around how location based services are NOT going to be the way of the future. Or more so, how they are not going to be as big as what we all think they are going to be and perhaps why we shouldn’t rely on them in their entirety.</p>
<p>The main negative arguments that have been presented in all my readings about location based services is predominately focused around some research which was conducted in the <a href="http://news.bbc.co.uk/2/hi/science/nature/7433128.stm" target="_blank"></a>UK by Dr William Webb from telecoms regulator OfCom. He discovered that of the 100,000 people tracked in his research – almost all of them had similar, if not identical, movement patterns day in, day out. This basically means that people don’t really change all that much – we move to work, using the same route that we use every day. We stay at work the majority of the day and then we go home. We don’t really explore other avenues of getting to and from work because it nonsensical to assume that we haven’t already mapped out the best way to get there already – so any sort of mobile location based service is not going to change our already proven best method. Additionally, lets say that it did find out a better route, we would then use that route everyday and not change from this newly discovered one again for some time. What&#8217;s interesting is that the research found that children and teenagers are much the same – they go to school using the same route every day and they spend the vast majority of their day at school. They then go home using the same route they took to school, and while they might deviate a little here and there to pick up food or go to a friend’s house – the overwhelming majority of their movement is within a 5KM to 10KM radius of their home and school.</p>
<p>So what does all this mean? Well, what seems to be the biggest trend in all this research is human consistency. People realistically don’t deviate from their typical everyday lives all that much. If you wrote down where you travelled day in and day out – you would discover that realistically you don’t really move more than a 10KM radius from your work or your home. When you are at work you might travel around a little or you remain stationary in the one place all day – when you are at home you go to the shops around your house, and commute to restaurants and use services within this limited area. Sure there will always be exceptions to this rule – so it’s not a blanket generalization, but what it is &#8211; <em>is what the vast majority of people do</em>. This also rings true for any interactions you have with your friends and colleagues. Most of the friends that you have, you have grown up with or you work with – and really you already know where they are located. Sure thing, you don’t know where they are located <em>all the time</em> but this then begs the question – do you really want to know? I have read arguments for and against this point and obviously the biggest factor in all of this has to do with privacy – perhaps something that deserves an entirely separate post in itself later.</p>
<p>So lets dig a little deeper &#8211; with the birth of ‘super’ smart phones (aka iPhone 3G) where you can be “always on” and your friends can interact with your every second of the day – how much will people really rely on location based services. I think it’s a moot point – I for one go to work each day and discover that only during the limited 1 hour I have for lunch would I look to see where my friends are located around my work. If they were within a close area of me, I would definitively give them a call or a message to hook up for lunch (of note is that I may already know they work close to me and so I don’t need to know this). Sure thing on a Friday night or around the weekend I would definitively use location based services more to find out what my friends are doing – but only if I could be bothered hooking up with them. If I didn’t want to go out – it’s pretty obvious that I should be able to “turn myself off” – which I think most location developers are on top of (or should be otherwise their service is going to have real privacy issues).</p>
<p>So where does that leave us? Well realistically the point that comes out in all these articles and all of research around location based services is that people don’t really change all that much. They go to the same places day in and day out, and the intrinsic similarity in their movement patterns suggests that they don’t like change.  Most people develop an affinity for the same coffee shop, super market, clothes stores and so on. If you find something that you like at one location, you won’t often change to another location but rather revisit that same location over and over again. So realistically, location based services are pretty useless when it comes to trying to get you to change – because the vast majority of research has found that people resent change. Have a think about this – if you love your local coffee shop just around the corner and within walking distance of your home, and then someone came and told you “No, no you have to try this cafe, it’s the best coffee in the world but it’s not a walk down the street, you have to drive” – what would you do? 95% of people couldn’t be bothered to try the new coffee shop until they were in that area and it was convenient to them. I love the coffee down at my local cafe, and there is no way I would drive to another cafe just to get coffee which is better but requires me to get in my car, dodge traffic, park, get out of the car, wait for the coffee, get back in my car, dodge traffic and return home. The stress alone of that exercise is enough to make it not worthwhile. It has to be <em>truly value adding</em> for you to want to go through this, and like most things in life &#8211; if it&#8217;s not going to be an &#8216;amazing experience&#8217;, rather just a &#8216;good one&#8217; &#8211; then you will not find yourself doing it. I can see some of you at the moment going &#8220;if the coffee was really unbelievable I would do it&#8221; &#8211; and maybe your thoughts really do have some merit to them, but I think in the vast <em>majority of cases</em> people rely on the age old adage “if it’s not broken, don’t fix it”.</p>
<p>So in conclusion however, and I say this as a big <em>however</em> – I think where location based services will come out on top is by letting you know what you friends and colleagues are doing at any given time. Sure thing, the argument that people don’t move far from their location is a valid one (and clearly proven) – but this doesn’t mean to say that location based services are entirely useless. A 10KM radius is still a huge area, and many people will want to know what their family, friends and colleagues are doing. Being able to <em>have the choice</em> of discovering new places and new friends with location based services is an offering that has previously never been accessible to the masses before – so perhaps people’s movements and consistency patterns may change. While it’s undoubtedly true that the majority of people are resistant to change – location based services will assist in allowing people to communicate with the people they want too, and ignore the ones they don&#8217;t want to deal with. <em>It’s all about choice</em> – if location based services can provide people with more choice than they already have in their lives – then it opens up a whole range of avenues that have never previously existed. Something I think, which is ultimately very very exciting.</p>
<p>Thoughts? Drop a comment below.</p>
]]></content:encoded>
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		<title>Location Based Services (LBS) Technology Overview</title>
		<link>http://www.timdavis.com.au/mobile/location-based-services-lbs-technology-overview/?utm_source=rss&#038;utm_medium=rss&#038;utm_campaign=location-based-services-lbs-technology-overview</link>
		<comments>http://www.timdavis.com.au/mobile/location-based-services-lbs-technology-overview/#comments</comments>
		<pubDate>Thu, 29 May 2008 06:19:50 +0000</pubDate>
		<dc:creator>Tim</dc:creator>
				<category><![CDATA[Mobile]]></category>
		<category><![CDATA[A-GPS]]></category>
		<category><![CDATA[GPS]]></category>
		<category><![CDATA[location]]></category>
		<category><![CDATA[location based services]]></category>

		<guid isPermaLink="false">http://www.timdavis.com.au/?p=22</guid>
		<description><![CDATA[<div class="addthis_toolbox addthis_default_style " addthis:url='http://www.timdavis.com.au/mobile/location-based-services-lbs-technology-overview/' addthis:title='Location Based Services (LBS) Technology Overview '  ><a class="addthis_button_facebook_like" fb:like:layout="button_count"></a><a class="addthis_button_tweet"></a><a class="addthis_counter addthis_pill_style"></a></div>Location Based Technologies I have often wondered whether people really understand Location Based Services (LBS) technology and whether they would like a bit more insight into how exactly location based services work, and more importantly – what information is actually passed from your phone to a server in order to establish your exact location co-ordinates. [...]]]></description>
			<content:encoded><![CDATA[<div class="addthis_toolbox addthis_default_style " addthis:url='http://www.timdavis.com.au/mobile/location-based-services-lbs-technology-overview/' addthis:title='Location Based Services (LBS) Technology Overview '  ><a class="addthis_button_facebook_like" fb:like:layout="button_count"></a><a class="addthis_button_tweet"></a><a class="addthis_counter addthis_pill_style"></a></div><p><img class="colorbox-22"  src="http://www.timdavis.com.au/wp-content/uploads/2007/10/tim_head.jpg" alt="Me" hspace="15" vspace="5" align="right" /></p>
<p><strong>Location Based Technologies</strong></p>
<p>I have often wondered whether people really understand Location Based  Services (LBS) technology and whether they would like a bit more insight into  how exactly location based services work, and more importantly – what  information is actually passed from your phone to a server in order to  establish your exact location co-ordinates. Most of the time, the accuracy of your  co-ordinates is entirely correlated to the accuracy of the method being used to  determine your location &#8211; such that some methods use mathematical  approximations to determine your location, and others use global positioning  data bounced from satellites to gain a more accurate understanding of your  position. Of course, some use a combination of both. All of the methods I will  explain below do, very much, depend on your surroundings as well. Obviously, if  you are surrounded by iron sheeting 100 meters underneath the ground &#8211; your  location will be pretty hard to determine. Conversely, if you are standing next  to a mobile phone tower and can see 5 other towers and have a clear vision of  the sky &#8211; your position is going to be very accurate.</p>
<p>I will make special mention now that all this information is entirely  understood by industry professionals, so nothing that I am going to detail here  is “secret” or contains some sort of “special sauce” which I know that other  people don’t. The idea of this post is to give people out there, who don’t know  really anything about Location Based Services (LBS), a better understanding of  the technologies which are utilized in a non-technical format.</p>
<p><strong>Parameters on your Phone</strong></p>
<p>Before I dive into an explanation about what types of location based  technologies are actually out there – a good place to start is what information  actually sits on your mobile phone which allows location based services to  actually work.</p>
<p>A typical mobile phone contains a whole bunch of communication information  which tells the mobile phone what network operator your mobile phone is  connected with, and how to optimize your mobile signal in order to ascertain  the best signal strength. You can usually access all this information by typing  in a special character combination on your mobile phone which will take you to  the engineering information screen. Most of you out there won’t really be all  that interested in checking this stuff out because it’s a whole bunch of  numbers that aren’t going to make sense – but for those that want too, just  search the internet for your handset model and the unique engineering unlock  code. It&#8217;s usually pretty easy to find.</p>
<p><em>So what information is available?</em></p>
<p>The information displayed on your phone varies from handset to handset, and  I do not recommend that you meddle with it. Sure thing you can view it, but do  not attempt to change predefined settings on your mobile phone or you  might render it useless. While I could go through all the information listed, I  am only going to focus on the location information that is really used as it’s  most relevant to this post. It’s below as follows:</p>
<ul type="disc">
<li><strong>AcsClas</strong> &#8211; Access priority class (not supported if 0000)</li>
<li><strong>MSTxPwr</strong> – Maximum allows transmit power in dBm</li>
<li><strong>MCC</strong> – Mobile Country Code</li>
<li><strong>MNC</strong> &#8211; Mobile Network Code.</li>
<li><strong>LAC</strong> &#8211; Location Area Code</li>
<li><strong>Cell ID       or CID</strong> &#8211; Base Station Identity</li>
<li><strong>Radio       Frequency (RF) Signal</strong>– The relevant signal strength between your       current tower and the adjacent one</li>
<li><strong>Hopping</strong> – Whether any frequency hopping is in operation</li>
<li><strong>DTX</strong> &#8211; Whether Discontinuous Transmission is in operation</li>
</ul>
<p>So what does all this stuff mean ? Basically, all this information informs  your network of where you are at any one time. This is done by your network  operator knowing the relevant latitude and longitude of all relevant base  stations – or mobile phone towers –  in your country and correlating this  information with the information shown above to determine your approximate  position <em>(this is called &#8216;network driven location approximation&#8217;)</em>.</p>
<p>For example, typically the process goes like this for <em>signal strength</em> or <em>time based</em> location identification:</p>
<ol type="1">
<li>Identification       of your MCC &amp; MNC occurs which recognizes the relevant country and       network operator you are in/with.</li>
<li>Identification       of the relevant LAC, or your location area code, to determine the       approximate regional area you are in.</li>
<li>Identification       of your Cell ID or CID &#8211; the relevant cell or mobile tower that your       mobile is connected too.</li>
<li>The       combination of your RF, Hopping and DTX allows both your network operator       and your mobile phone to ascertain which signal is the stronger, and       thereby determine a priority of mobile base stations (Cell IDs) with which       your mobile should be connected. This can be done through signal strength       and timing responses of your phone with the relevant cell tower.</li>
<li>Because       your network operator has a database of relevant latitude and longitudes       of all Cell IDs, or mobile base stations, they are then able to       approximate your position using “triangulation” or “quadrangulation”       techniques.</li>
<li>These       techniques typically use a complex mathematical method of determining your       location, which really relies on the good old Pythagoras theorem you were       taught in school. For triangulation, this is then combined with a       calculation to determine the barycenter of the mobile base tower       &#8216;triangle&#8217; (determined by the strongest three base stations) to determine       your approximate position. <em>(I&#8217;m not going to go into quadrangulation       but you get the gist!)</em></li>
</ol>
<p>It’s important to realize that what I have just detailed is a really  simplistic overview of a network method of location identification &#8211; in real  life it&#8217;s quite complex. Additionally, the method illustrated above is really  just for network identification using <em>signal strength</em> or <em>timing based</em> calculations. There are, of course, many other methods, as well as hybrid  combination&#8217;s of these technologies which is all detailed in the next section.</p>
<p><strong>Location Based Service Position Technologies</strong></p>
<p>OK, so we have briefly covered what’s available in your mobile phone as well  as how your mobile and network operators use this information. Now let’s cover  what technologies are out there, the pro&#8217;s-and-con&#8217;s of each and an overall  conclusion.</p>
<p>Here is a table that covers the main types of location technologies out  there:</p>
<table border="1" cellspacing="0" cellpadding="0">
<tbody>
<tr>
<td width="136"></td>
<td width="177"><strong>Location Accuracy</strong></td>
<td width="121"><strong>Time to Fix</strong></td>
<td width="316"><strong>Prerequisites </strong></td>
</tr>
<tr>
<td><strong>GPS</strong></td>
<td>High Precision“Sky Line of Sight”</p>
<p>5-20m</td>
<td>~ 10-15 mins start</p>
<p>~ 1-2 sec updates</td>
<td>Device support only (HW)</td>
</tr>
<tr>
<td><strong>A-GPS</strong></td>
<td>Very High</p>
<p>Requires “Sky Line of Sight” 5-50m</td>
<td>~ 10-40 sec start</p>
<p>~ 5-10 sec updates</td>
<td>Requires specific device support Hardware(HW), GPS    reference network.</td>
</tr>
<tr>
<td><strong>OTDOA (WCDMA)</strong></p>
<p><strong>E-OTD (GSM)</strong></p>
<p><strong>AFLT (CDMA)</strong></td>
<td>Medium Strength</p>
<p>Depends on cell density 40-400m</td>
<td>~ 6-10 seconds</td>
<td>Requires Base Station Support (BSS), MSC and HLR support    and usually always requires</p>
<p>network operator involvement</td>
</tr>
<tr>
<td><strong>Cell-ID</strong></td>
<td>Quite Weak</p>
<p>Dependent on cell density</p>
<p>Between 100-5500m</td>
<td>~ 4-8 seconds</td>
<td>Needs Mobile Switch Center (MSC) and Home Location    Register (HLR) support, or requires device and Cell-ID database.</td>
</tr>
<tr>
<td><strong>WiFi</strong></td>
<td>Quite Strong</p>
<p>Dependent on WiFi AP density</p>
<p>&lt; 50-250m</td>
<td>~ 4-8 seconds</td>
<td>Device and network support.</p>
<p>Requires WiFi DB.</td>
</tr>
</tbody>
</table>
<p><strong>Summary of the Table</strong></p>
<p><em>GPS</em></p>
<p>Global Positioning Systems are basically a series of 24 (now 32 as of March  2008) Medium Earth Orbit Satellites (around 12,500 miles above the earth) which  transmit exact microwave signals that allow GPS receivers to determine their  exact location, speed, direction and time. A GPS receiver calculates your  position by timing the signals sent by the GPS Satellites to your current  location on Earth, and the receiver uses the arrival time of each signal to  measure the distance to each satellite. Trialateration (triangulation) is used  to determine the device&#8217;s location given the number of signals received from  each relative satellite, and this information is then decoded into useful  formats such as latitude and longitude. Typically, latitude, longitude, time  and altitude are the 4 data sets that need to be interpreted &#8211; with the  position time being relative to the GPS information and signal quality. This is  why you need a clear <em>&#8216;line of site&#8217; </em>with the sky in order for GPS to  really work effectively because the receiver must have constant signal  connection with a least 3 satellites in order to accurately determine your  position.</p>
<p><em>Assisted GPS or A-GPS </em></p>
<p>This type of technology has garnered a whole bunch of attention recently  because A-GPS is what is contained in the new iPhone 3G. Assisted GPS is  basically an improvement on GPS because it combines the information received  from satellites, with the information from your local base station. As  explained previously, your mobile phone is connected to a relative base station  or wireless network at any particular point during the day. Assisted GPS  basically takes the known location of this base station and combines it with  the information gathered from the GPS chip to improve the relative speed of locating  your exact position. If your GPS chip is able to already have an approximate  idea of where it is located on the planet, then it is able to look specifically  for satellites in the region where you are located, instead of scanning for  random signals and interpreting them. By using available network information,  your GPS chip can more easily narrow its vision to search for signals in your  current country and region. This basically reduces the <em>time to fix</em> your  location because the data being collected improves the quality of the GPS  receiver.</p>
<p>The biggest issue with Assisted GPS is of course, its reliance on the  network operator to provide network data to the GPS chip. As indicated, for  A-GPS to work, it requires the network operator to provide some information  about the Cell ID in order to ascertain the relative, or approximate, latitude  and longitude of the device. Alternatively, this information can be provided by  WiFi network connections assuming they have position information contained in  them, and WiFi is supported by the device.</p>
<p><em>Cell ID (or Base Station)/ WiFi Databases</em></p>
<p>Mobile devices must always have a relative wireless access point (for Wifi  devices) or base station in order to determine the location of the device. The  simplest example of location identification using this method is when you see  your neighborhood or suburb name on the main screen of your phone. Your Cell ID  or WAP point is transmitted to your network operator who is able to determine  where you are located generally.</p>
<p>More recently, third party databases are being gathered in order to take  away the potential monopoly that network operators have around this  information. Google, for example, has been gathering this information by  getting GPS users to download their mapping applications onto their phones, and  then pairing your current GPS co-ordinates with your network information to map  out every wireless access point and base station available. They do this by  matching the signal strength and timing information, with the relevant MCC, MNC  and Cell ID your mobile phone is connected with, and matching this up with your  current latitude and longitude information passed from your GPS receiver &#8211; all  this information in then bundled up and passed to the Google servers. This  allows them to generate an approximate estimation of where exactly the base  station is located and subsequently triangulating your location. No doubt, they  also combine this with information contained in the current map tile you were  viewing on the Google mapping application. All this information allows them to  have a very extensive, and a very valuable location database. Of course, there  are other companies doing the same thing in order to resell this information. <a title="Skyhook" href="http://www.skyhookwireless.com/" target="_blank">SkyHook</a> is a company which is basically  hiring people to drive around in cars in all sorts of cities around the world  to gather Wifi access point information and then resell this to developers who  want location information. It&#8217;s really a combination of these methods which is  going to provide the best location information moving forward.</p>
<p>WiFi databases basically take advantage of relevant Service Set Identifier  (SSID) and Media Access Control (MAC) addresses of access points constantly.  When you hook up your wireless router at home for example, you will notice the  relevant SSID and MAC addresses when connecting to your wireless network. The  MAC address is basically the unique device identifier which can be used to  roughly identify where the receiving signal is coming from. As you would know  from your home laptop or mobile device -most WiFi signals can only really  extend a maximum distance of 50m-200m and so the position information from WiFi  stations can be quite useful for easily determining your location. The obvious  disadvantage is that you need to know hundreds of access points in order to  make up a meaningful and worthwhile location database.</p>
<p><em>Signal Strength Triangulation</em></p>
<p>The example I provided in the mobile engineering information section above  really explains how this process works. Basically, by leveraging the relative  radio frequency (RF) of the signal strengths in the device and incorporating  the base station information, a position is able to be determined. As explained  previously, the complexity of the mathematics behind determining your location  is really dependent on the quality of the data in the database. RF  fingerprinting really looks at relative signal strengths of the base stations  that the device is connected too, and prioritizes them in order to get the  three strongest signals (triangulation). Basically, it then calculates the  propagation of the RF signals and uses this to estimate your position relative  to the latitude and longitude of the base stations. This type of method has  been the most commonly used method of location identification because GPS and  A-GPS chips are not widely available in mobile phones yet &#8211; although this is  rapidly changing.</p>
<p><em>Time-Based Triangulation</em></p>
<p>Again, the example I provided at the beginning explains how this works broadly.  The slight difference time-based triangulation has to signal strength  triangulation, is that it looks at the relevant signal timing information from  the network in order to ascertain your relative position to nearby base  stations. Time Difference of Arrival (TDOA) and Advanced Forward link  Triangulation (AFLT) are the most common methods of location determination  under time-based identification. The biggest difference between the two methods  (TDOA v AFLT) is where the timing difference is measured &#8211; either in the device  itself or in the network. TDOA is the more complex method and makes it  impossible for third party vendors to use this it because the calculation is  done inside the network. This makes TDOA a &#8220;LBS network operator  monopoly&#8221; method. The AFLT method is a CDMA method and uses CDMA as  opposed to the more common GSM to make the position known. The other method  which is worth a mention is the Enhanced Cell-ID method which incorporates both  signal strength and timing data received from GSM signals in order calculate an  in-network position. Again, this is a difficult method to commercialize because  of the network operator reliance on calculating the timing of the signal.  Network triangulation is really around 50m-500m in accuracy.</p>
<p><strong>Conclusion</strong></p>
<p>I could continue writing all day about which method is better, which has a  better timing-to-fix and which is the best fall back option &#8211; but it seems this  post has already gone on long enough. Obviously, there are a whole bunch of  factors that I haven&#8217;t mentioned such as hardware reliance, chip quality,  battery and CPU drain and other general aspects of wireless and mobile devices  that must be taken into consideration. I haven&#8217;t gone into these areas  predominately because they are factors that need to be considered by developers  only and not by the people who just want to understand location based services  and technology generally. I will mention, however, which is the LBS method is  the best.</p>
<p><em>None of them : P</em></p>
<p>The reason for this is because it&#8217;s combination of all of them which makes  LBS useful. When it is apparent that one method is clearly working really well,  and another is not, then this is the most suitable method to be used &#8211; it&#8217;s  that simple. The <em>real key</em> is to have a number of methods available in your  device so that the best method is always utilized at the right occasion. This  is why in some respect that A-GPS is one of the best LBS techniques -although  it&#8217;s not all that common at the moment in mobile phones &#8211; because you get the  best of both worlds by having GPS and Network Information determining your  location at any one time. With that said, as I stated at the start, the  strengths and weaknesses of each technique always come down to the environment  you are located in, and the current conditions within this environment.</p>
<p>Either way, all in all &#8211; I hope this helps any confusion you&#8217;ve had!</p>
<p>Feel Free to Contact Me at any time with your questions.</p>
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