Tuesday, January 31, 2006

Sharing and Sending Web Content and More Via SMS

I'm constantly sending reminders to myself and others via SMS (text messaging). In today's SearchDay overview of the new Google Toolbar 4 for IE (beta), Chris points out that a new feature built into the toolbar allows the user to send web content via SMS (or via Gmail or Blogger) to any other SMS user in the U.S. Very cool! Google also offers a "Send to Phone" (U.S. numbers only) extension for Firefox.
Another service that you might want to check out (also free) is called Vazu.
This service requires a small app (free) and allows the user to cut and paste text from web pages, send files, images, and more via SMS to anyone with access to SMS in the U.S. or Canada. Sending content is free with Vazu but of course, make sure you know how much your wireless plan charges to receive messages. With non-text material you'll need to also have a mobile web browser to view an image or download a file.
More about the phone providers that Vazu is compatible with here. You can even integrate with Outlook. The Vazu client app is available for Windows (2000 or XP) and a widget is available for Mac OS X. The service is compatible with IE and Firefox. Btw, IE users will also want to check out the often useful "Contact Detector" feature.
Also, Yahoo Local and Yahoo Maps, and Yahoo Shopping also provide a send-to-phone features that let the user to receive driving directions, merchant info, and pricing data via SMS. Look for the "Send to Phone" link. More info here.
Posted by Gary Price on Jan. 30, 2006

Phone start-up takes on Google
Simon Hayes
JANUARY 31, 2006
AN Adelaide software startup is spoiling for a brawl with Google as it prepares for the launch of a technology that allows internet users to click on any phone number to set up an instant call.
Pep-Talk International has patented on-the-fly conversion of phone numbers into telephone calls, allowing it to sell the service to companies that want to receive instant feedback from customers.
The patent sets it up in competition with Google, which is offering click-to-call on Google Ads.
The company is launching the service with the help of an $80,000 federal Government COMET (Commercialising Emerging Technologies) grant.
It is willing to take on external investors.
"The patent is for converting phone numbers into clickable phone calls on the fly," Pep-Talk marketing and sales director Bill Oborn said.
"With Google Ads they integrate the phone number with their switch."
Pep-Talk is a spin-off of SkunkWorks, an Adelaide telecommunications services company.
It has been testing the technology with Australian customers and is planning to take it overseas shortly.
SkunkWorks offers services including billing, voicemail and SMS alerts.
Internet users do not need to download software to use Pep-Talk. They either visit the website of a company that subscribes or surf the web through the Pep-Talk portal.
Pep-Talk is tipping a number of business models, ranging from a company subscribing to click-enable its phone numbers, to a revenue-sharing deal with a telecommunications carrier.
"Pep-Talk turns any phone number in an email, a directory, or even a search engine, into a clickable phone call," Mr Oborn said. "We don't need to integrate into anyone's back-end.
"You just click on the phone link, and two phones ring, yours and the company's.
"The company pays for the incoming call in the same way it would pay for an 1800 call."
Apart from live calls via Google Ads, Pep-Talk faces competition from LivePerson, which offers text-based instant-help calls, and voice over internet protocol applications such as Skype.
Pep-Talk's advantage was that users did not have to download software, and service providers did not have to do any integration work, Mr Oborn said.
"Our service is ubiquitous," he said.
"Skype is great and has its place, but right now our product is ubiquitous. Anyone in the world who has a phone can use it."
The self-funded company would use the COMET grant, signed recently, to finance Pep-Talk, he said.
"We can grow organically because we are a cashed-up, self-funded organisation.
"If a big partner came along and wanted to play with us, then absolutely.
"It's such a hot space."
The Australian

Saturday, January 28, 2006

gps tracklog: Pros and Cons of PDA-based GPS Receivers

Since I'm running my first review of a PDA-based GPS receiver today, I thought I would briefly cover the advantages and disadvantages of these units, compared to traditional handheld GPS receivers:

Pros:

Ability to display raster maps.
Can perform more functions (word processor, datebook, MP3 player, Bluetooth, etc.).
Larger screen.

Cons:

More fragile than most handheld GPS receivers, which are "ruggedized." This is primarily due to the touch screen.
Shorter battery life than most handheld GPS receivers.

The bottom line is that these can be a good solution for automotive navigation or paperless geocaching, but they aren't a good choice for backcountry navigation.

Google Maps Mania: Google Maps Creation Tools and Resources

Looking for Google Maps Mashups? Scroll down to earlier posts or check here

Google Maps Creation Tools:

Create Google Earth .kmz files quickly and easily using Google Maps - Watch this demo
DIY Map - New Google Maps creator lets you export your map to your blog. (Guide Page)
Google Maps for your Apps - An excellent CD training course from GeoSpatialTraining.com
How to add a Google Map to any web page in less than 10 minutes
SiteMapper - Create a custom Google Map for your website [via]
How-To:A Google Maps mash-up - (Java World) Integrate external data with the Google Maps API
HOW TO: Google Maps + Blogger, Drupal (and more Drupal)
GeoID - Mapping Website Visitors
More Creation Tools here

Web Tools that use Google Maps:

NextHop - Take multiple addresses and create a map that arks out locations and a path to travel
AJAX Powered IP Location Lookup
New Traceroute Tool - Traceroute by IP address or host name to Google Map the path the packets take
Understanding Graph Searches Through Animated Google Maps

Applications that are now using Google Maps:

GTalk Profile - Find other Google Talk users in other parts of the world
Gizmo Internet Phone App uses Google Maps
Mozilla Thunderbird 1.5 uses Google Maps
New Firefox Extension: Get a Google Map and driving directions for any text selection from a webpage
Squidoo.com - Now has a Google Maps module

Related to the Google Maps API:

Do this now: Apply the Firefox 1.5 fix to your mashup!
An easy way to add Google Maps using Cartographer (Rails)
Google Maps to Panoramio user script
JavaScript temporarily forked - A post Jan.3/06 from the Official Google Maps API Blog.
GIS Shapefiles to Google Maps and Google Earth
OpenStreetMap Data + Google Maps - More info here [via]
Polygon Creator Using Google Maps
Batch GeoCode - geocode addresses in batches (up to 50,000 addresses per day, but it works best to do it in 500 address chunks.) [via]
Google Maps API Group: Tabbed info windows in API v2
A heated thread on the API group

Other related sections here on Google Maps Mania:

WorldTracker SMS - Small GPS Tracking | GPS Lodge.com

WorldTracker SMS - Small GPS Tracking

WorldTracker SMS is a pretty small device that can track just about anything you want providing real time updates to you via SMS to your moile phone or PDA. When placed with packages, vehicles, or personnel, the WorldTracker SMS provides detailed reports of routes traveled for quality-control and security purposes. The data can also be seen through Google Earth which is a great option to visualize the data.

Featuring SiRF star III technology for extra sensitive reception outdoors, indoors and through metal. WASS enabled receiver providing GPS signal corrections, giving better position accuracy. How much better? Try an average of up to five times better. A WAAS-capable receiver can give you a position accuracy of better than three meters 95 percent of the time.

WORLDTRACKER SMS provides real-time navigation in urban canyons as well as high sensitivity acquisition needed for indoor use.

The package includes a pre-activated SIM card. Website tracking access is available at a cost of US $89.95 per year. Other charges include $39.95 per month for 300 SMS messages or $59.95 per month for unlimited messages.

ReadMore at the company website

ReadMore at GPS World magazine for coverage on the WorldTracker SMS.

Google Maps news and blog post roundup

What's fuelling the appeal of Google Earth?
Travolution - Jan.25/06
Using Google for Profit: Data Point
AllPointsBlog - Jan.24/05
Google Earth Growth - What's Behind it?
HitWise Blog - Jan.24/06
Google Maps is the #3 return on a Google search for "maps"
SeanBonner.com - Jan.23/06
Terrific Real Estate Search Tools
SearchEngineWatch.com - Jan.23/06
O'Reilly: "Google Maps is the new open source."
AllPointsBlog - Jan.22/06
Google eye in the sky catches flying car
Sploid.com - Jan.23/06
Tour New York with a Google-Wikipedia-GPS mashup
C|Net Google Blog - Jan.18/06
Still Seeing "Blue Pins" on Some Google Maps; Google Now Testing Paid Links in Google Earth
Search Engine Watch - Jan.18/06
Hot: Real Estate Industry Uses of Satellite/Aerial Imagery
Search Engine Watch - Jan.17/06
Search engines going far beyond maps
SeattlePi.com - Jan.15/06
A Better Way to Do the Monster Mash
Baseline - Jan.14/06
Want Google Local to Look/Act Like Live Local?
AllPointsBlog - Jan.9/06
Google Maps and your alumni!
Wired Communities - Jan.9/06
[Book Review] Google Maps API: Adding 'Where' to Your Applications
The Farm Tucows Blog - Jan.5/06
Update on Mashup Camp
ZDNet Blogs - Jan.4/06
Man Hacks The Internet To Plot Amazon Wishlists Users Home Addresses on Google Maps
Pay Attention To Me! - Jan.4/06
"My New Business Card", Google maps based
Will.Boerland.com - Jan.3/06
Cheney's Residence and Google Maps

With LBS, It's All About "Getting to Free"

Today, I met with Joe Herzog, Director of Emerging Products and Eric Larson, Product Manager for Directories at InfoSpace, a company focused on mobile phone applications, many with a location context. Herzog said that while today you will be paying a subscription fee for mobile location-based service "it's all about getting to free." Herzog thinks the current business models are not necessarily the ones that will be viable over the long run. "Calls and clicks" is the revenue model of most mobile phone operators and the location-based services that people will demand must be a part of that same model. Herzog believes that LBS applications should be free, or at least transparently so, to the user. The LBS app will just chew up more minutes and hence a larger return to the operator. However, in the near term, look for LBS subscription plans to be in the $2 - $3 per month fee range.

Location-Based Services Offer High Revenue Potential in Competitive Mobile Communications Market

Location-based services (LBS) have been increasingly on the radar screen for a wide variety of carriers according to Frost & Sullivan. Additionally, revenue in this industry totaled just $91.2 million in 2004 and can reach over $600 million by 2008

PALO ALTO, Calif., Jan. 16 -- There has been intense scrutiny on how LBS initiatives can enhance average revenue per user (ARPU) and reduce churn. Frost & Sullivan (http://www.wireless.frost.com ) reveals that revenue in this industry totaled just $91.2 million in 2004 and can reach over $600 million by 2008.

If you are interested in a virtual brochure, which provides manufacturers, end users and other industry participants an overview of the latest analysis of the U.S. Consumer Location-based Service Markets - Enhancing Carrier ARPU Through LBS, then send an email to Mireya Castilla, Corporate Communications at mireya.castilla@frost.com with the following information: your full name, company name, title, telephone number, e-mail address, city, state, and country. We will send you the information via email upon receipt of the above information.

"The variety and breadth of possible applications and services in LBS, from pure content and advertising, to emergency 911 (E911), navigational aids, social networking, and tracking services highlight its adaptability," explains Frost & Sullivan Industry Research Manager Brent Iadarola. "Research on trends in LBS adoption indicates that companies regard location as a 'killer- enabler' to existing services, rather than chase the elusive next 'killer application'."

Middleware platforms leveraging advancements in location determination technologies and the proliferation of assisted global positioning system (A-GPS) handsets comprise the essential ingredients for a compelling, commercial LBS suite moving into place.

With high overall performance and widespread location coverage even in areas of low-cell density, A-GPS is likely to emerge as the long-term technology of choice for operators in North America. Carriers' decision whether to spread capital expenditures over a greater period of time and provide incremental services to customers will affect their future. By delaying services, the carriers may be able to save costs on intermediate infrastructure; however, they risk losing customers to competitors with first mover advantages.

"In contrast to fixed Internet, users in the mobile environment are demanding personalized, localized, and timely access to content and services," explains Iadarola. "LBS with user-friendly application categories such as mobile resource management (MRM), entertainment, information services, and security services are likely to be successful commercially."

The aggressive marketing of commercial LBS, growing traction of LBS offerings, as well as sophisticated and integrated LBS are some of the main factors that are likely to heighten the growth and revenue potential of these services in the future.

U.S. Consumer Location-based Service Markets - Enhancing Carrier ARPU Through LBS is part of the Next Generation Mobile Communications Subscription that evaluates the competitive landscape of LBS in the United States. It also assesses technologies such as A-GPS, EOTD, U-TDOA, AFLT, Cell ID and discusses dueling architectures such as control and user plane. This research service also includes market forecasts, application trends and data on usage trends. Executive summaries and analyst interviews are available to the press.

Frost & Sullivan, a global growth consulting company, has been partnering with clients to support the development of innovative strategies for more than 40 years. The company's industry expertise integrates growth consulting, growth partnership services, and corporate management training to identify and develop opportunities. Frost & Sullivan serves an extensive clientele that includes Global 1000 companies, emerging companies, and the investment community by providing comprehensive industry coverage that reflects a unique global perspective and combines ongoing analysis of markets, technologies, econometrics, and demographics. For more information, visit http://www.frost.com

Going to Market with Location Services | January 19, 2006 | Telecommunications Magazine

It may not be long before house hunters making the rounds of local open houses on a Sunday afternoon no longer have to clip classified ads or download property sales blogs from the Internet to guide their search.

They could simply use their cell phones to connect with a location service to which they subscribe, get a read of their location within five to 20 yards, and through their mobile devices receive all the open house locations taking place that afternoon in the vicinity.

In addition, their phones will have access to photos of each property, the open-house times, and the contact numbers of the realtors hosting the showings.

s advertisers start to understand their options in niche marketing and break out of decades-old patterns of making sweeping media buys, the above scenario presents a compelling way for advertisers to reach the audiences they need to reach, and for consumers to get the information they need, exactly when they need it.

With this, mass marketing evolves into direct marketing, direct marketing branches out into segmented marketing, and ultimately runs through multiple filters as micro-marketing. More and more industries are thinking creatively about how to market to a segment of one. Mobile devices can provide the mechanism.

Indeed, while other new forms of marketing are optimally relevant and highly targeted, location-based services are being viewed increasingly as one of the most powerful new tools available to marketers to achieve that goal.

Location-based services have the capacity to be highly interactive, spontaneous, flexible, and easily reprogrammed with new types of offerings. Carriers have a worthwhile challenge in turning their technology businesses into a unique marketing opportunity.

As touched upon in the previous articles in our series, European and Asian carriers have already figured out how to use existing networks and GPS technology to pinpoint a subscriber’s location, sending compelling merchant offers to users. On those continents, these offers are taking the form of vodcasts, podcasts, breaking news, music or 2-for-1 limited time offers at a nearby store.

While the drivers for location-based services in Europe and Asia have been primarily commercial, the primary driver in the U.S. has been safety. The FCC mandated that by December 2005 cellular carriers needed to be able to locate anyone making an emergency 911 call.

Dubbed the Wireless Enhanced 911 (E911) Rules, the goal was to improve the effectiveness and reliability of wireless 911 services by providing dispatchers with additional information on wireless 911 calls.

While the E911 program has been divided into two phases, the endgame is for wireless carriers to have the capability to locate a call within 50 to 300 meters in most cases. As such, location has become an FCC mandated piece of wireless telecom infrastructure. It is the job of carriers to manage customer migration to a service that encompasses location, and to hardware that enables it.

As challenges of accuracy are resolved, the carriers are advised strongly to develop privacy principals so that any issues around privacy considerations can be built into the infrastructure and hardware. Worries over privacy encompass concerns such as, do consumers want their friends, let alone retailers or coffee houses, to know their every move, and would location users be able to turn off location at the flip of a switch?

Examining these concerns can help dictate which technology ultimately is used. There is little point in having a set of technology standards and then realizing that the infrastructure cannot support such important issues. But once outlined, location could even be a way for carriers to sell upgraded handsets, not only the services themselves.

By Invitation Only Mobile devices are one of the few channels where consumers can ‘invite’ businesses to market and communicate with them. Consumers sign up for desired services when they subscribe to a particular service. By understanding these behaviors, marketers can determine the best information to push out to the consumer.

But marketers should tread lightly. There are four important rules of engagement:

1. A cell phone will allow content to be driven to them. Consumers do not want SPAM on their mobile phones. It’s costly for some and annoying for others, both reasons for a consumer to change carriers very quickly. Users want to set the parameters on the marketing and services they receive, and this wish should be respected.

2. Marketers have to create a compelling reason for customers to invite retailers into their world. Knowing what meaningful content means to most wireless device users can be a challenge. Keep in mind that content should offer the ability to do something that is time sensitive and crucial. Offer compelling content that is meaningful and relevant.

Location-based services are a good example of compelling content. People are busier than ever and increasingly are looking for marketers to filter choices based on preferences. Always short of time, they want to squeeze in extra activities in an hour.

A parent running from activity to activity on a weekend with children in tow would probably be happy to be provided the location of the nearest ATM or the name and address of a family friendly restaurant, special offers on clothing, or a list of G-rated movies. With such offers, mobile phones simplify parent choices and enable them to get more done in the given time.

3. Build trust through brand recognition. Build trust and the consumer will invite you in. Our research has shown, for example, that when consumers are shown a brand they trust, they are more likely to sign up for a service provided by that company.

For example, when consumers realize they consistently can get quick access to cash by using a well-designed ATM location service, they will tend to be more loyal to the business that provides the information— whether it is their bank, their mobile carrier or their Internet service provider. Once consumers arrive at the location they have been directed to, the experience they have at the ATM or the merchant will be a branded experience. This familiarity promotes a feeling of security and reinforces loyalty.

4. Establish information partnerships. Time and investment can be minimized if a business works with an information partner to enhance its current services with new offerings of high value to its customers. Carriers can gain access to a robust data network, allowing them to communicate directly with customers through easy, sophisticated information solutions.

Moreover, an information partner can help the business integrate existing data and systems smoothly, and develop new content and new services.

The information partner will also be able to help with mainstream marketing to build awareness about a service or content. Once consumers have opted in for the content through their personal mobile devices, the partner can help create a unique experience for the users.

The most important lesson for this consideration is that while there’s a strong tendency to think about technology, the focus needs to be on what consumers want and how they can most easily access it.

While mobile is well positioned to become the new marketing channel and technology will allow mobile devices to become fully functional, carriers are going to have a limited shot at marketing the technology to support the right programs for the right consumers. If they get it wrong the first time, customers will be very reluctant to try it a second time, no matter how much the offer has improved.

Jonathan Cetnarski is the global practice leader of information products and services for MasterCard Advisors™, LLC, the consulting arm of MasterCard International.

Going to Market with Location Services | January 19, 2006 | Telecommunications Magazine

In addition, their phones will have access to photos of each property, the open-house times, and the contact numbers of the realtors hosting the showings.

But marketers should tread lightly. There are four important rules of engagement:

Moreover, an information partner can help the business integrate existing data and systems smoothly, and develop new content and new services.

Jonathan Cetnarski is the global practice leader of information products and services for MasterCard Advisors™, LLC, the consulting arm of MasterCard International.

Chapter 3. Sources of Inaccuracy: The Problems

In our discussion of measuring distances using patterns of numbers, we assumed that you and your friend started counting numbers simultaneously. If your watch is one second off, this will translate into 344 meters of error in measuring distance, because sound travels 344 meters in one second. With satellites, the electronic signals travel about 300,000,000 meters per second (the speed of light). So the errors in the satellite clock and the receiver clock contribute profoundly to errors in distance measurements.

Satellite Clock

One billionth of a second (one nanosecond) of inaccuracy in a satellite clock results in about 30 centimeters (one foot) of error in measuring the distance to that satellite. For this reason, the satellites are equipped with very accurate (Cesium) atomic clocks. Even these very accurate clocks accumulate an error of 1 billionth of a second every three hours. To resolve the satellite clock drifts, they are continuously monitored by ground stations and compared with the master control clock systems that are combinations of more than 10 very accurate atomic clocks. The errors and drifts of the satellites' clock are calculated and included in the messages that are transmitted by the satellites. In computing the distance to the satellites, GPS receivers subtract the satellite clock errors from the reported transmit time to come up with the true signal travel time.

Even with the best efforts of the control centers in monitoring the behavior of each satellite clock, their errors cannot be precisely determined. Any remaining satellite clock errors accumulate typically to about a few nanoseconds, which cause a distance error of about one meter.

Receiver Clock

Similar to satellite clock errors, any error in the receiver clock causes inaccuracy in distance measurements. However, it is not practical to equip receivers with very accurate atomic clocks. Atomic clocks weigh more than 20 kilograms, cost about US$50,000, and require extensive care in temperature control.

Assume that at a given time our receiver clock has an error of one millisecond, causing a distance error of about 300,000 meters. If the distances to all satellites are measured exactly at the same time, then they are all off by the same amount of 300,000 meters. We can, therefore, include the receiver clock error as one of the unknowns that we must solve for. Remember from Chapter 1 that we had three unknowns (X, Y, Z) for the position. Now we have four unknowns: three components of position and the new unknown of receiver clock error. We will need four equations in order to solve for the four unknown. Measuring distances to four satellites can provide us such four necessary equations. Instead of three satellites before, now we need four, but in return we can use inexpensive clocks in our GPS receivers.

Note that the concept of receiver clock being one of the unknowns is valid only if we take measurements to all satellites exactly at the same time. If distances to all satellites are not measured at the same time, then for each measurement we have a different clock.

Making simultaneous measurements to four satellites, we not only compute the three dimensions of our position, but we also find the error in our receiver clock with very good accuracy. A typical clock has a drift of about 1000 nanoseconds every second, but we can now adjust the receiver time to the accuracy of the GPS clock. This will make the inexpensive clock of the receiver as good as an atomic clock. Receivers correct their clock every second and provide a corrected tic signal for outside use for those who need accurate time. If we put a receiver in a precisely known location, then we need to track only one satellite to continuously calculate the receiver clock error and adjust it.

Four is the minimum number of satellites that we need to compute position and time. The more satellites we have the more accurate results we can get. This is discussed later in the GDOP section.

Satellite Orbit Error

As we discussed before, the accuracy of our computed position also depends on how accurately we know the location of the satellites (the points of references). The orbits of satellites are monitored continuously from several monitoring stations around the earth and their predicted orbital information is transmitted to the satellites, which they in turn transmit to the receivers. The history of GPS has shown, thus far, that the accuracy of the orbital prediction is in the order of a few meters. This will create about a few meters of error in computing our position. In the next chapter we shall see how to remove this error.

Atmospheric Errors: Ionosphere and Troposphere

Ionosphere

In computing distances to satellites, we first measure the time it takes for the satellite signal to reach the receiver and then we multiply this by the speed of light. The problem is that the speed of light varies due to atmospheric conditions. The upper layer of the atmosphere, called the ionosphere, contains charged particles that slow down the code and speed up the carrier.

The magnitude of the effect of the ionosphere is much more during the day than during the night. The magnitude also has a cyclical period of 11 years that reaches a maximum and a minimum. For the current cycle, the ionosphere will reach its peak magnitude in 1998 and its minimum in 2004. The cycle will then be repeated. The effects of the ionosphere, if not mitigated, can introduce measurement errors greater than 10 meters.

Some receivers use a mathematical model for the effects of the ionosphere. With the approximate knowledge of the density of the charged particles in the ionosphere (broadcast by satellites), the effect of the ionosphere can be reduced by about 50%. The remaining error is still significant.

The impact of the ionosphere on electronic signals depends on the frequency of the signal. The higher the frequency, the less is the impact. So if we transmit the patterns simultaneously via two different frequencies, the ionosphere may delay the code on one frequency, for example, by 5 meters and on the other frequency, say, by 6 meters. We cannot measure the magnitude of these delays, but we can measure their difference by observing the difference on their arrival time, which in this case translates into 1 meter of effective distance between them. By measuring this difference and using known formula for frequency dependency of the ionosphere delay, ionosphere effect can be removed.

It is exactly for this reason that all GPS satellites transmit information in two frequencies, called L1 and L2. Precision receivers track both signals to remove the effect of the ionosphere. All non-precision receivers track only the L1 signal. This is one of the main distinguishing features between different types of receivers. The L1 receivers are also called single frequency receivers, while the receivers that track L1 and L2 are called dual frequency receivers. Dual frequency receivers practically remove the ionosphere effects.

Since the L2 signal is not entirely available to the general public, sophisticated techniques have been implemented in receivers to extract the code and carrier information, even with the partial availability of the L2 signal. These techniques fully satisfy the requirements of the users for non-military applications, while not compromising the Anti Spoof policy and security objectives of the US Department Of Defense (DOD).

There has been some discussion on allowing a different frequency for civilian applications to separate the DOD and civilian requirements. We believe, however, that the existing system fully satisfies the civilian requirement, particularly since advancements in electronics integration have made the technology affordable for broad civilian applications.

Troposphere

The lower level of the atmosphere, which contains water vapors, is called the troposphere. It has the effect of slowing down both code and carrier. The effects of the troposphere cannot be removed using dual frequency systems. The only way to remove the effects of the troposphere is by measuring its water vapor content, temperature and pressure, and applying a mathematical model that can compute the delay of the troposphere.

Multipath

In measuring the distance to each satellite, we assume that the satellite signal travels directly from the satellite to the antenna of the receiver. But in addition to the direct signal, there are reflected signals, from the ground and the objects near the antenna, that also reach the antenna through indirect paths and interfere with the direct signal. The compound signal creates an uncertainty about the true signal arrival time, much the same way as the echo from nearby mountains may cause uncertainty in the exact time you hear your friend's voice. If the indirect path is considerably longer than the direct path (more than 10 meters) such that the two patterns of signals can be separated, then the multipath effect can be substantially reduced by signal processing techniques.

Receiver Errors

Receivers may introduce some errors by themselves in measuring code or carrier. In high quality receivers, however, these errors are negligible (less than one millimeter) for carrier phase and a few centimeters for code phase.

Geometric Dilution Of Precision (GDOP)

We have been talking about the errors in measuring distances to satellites, which are commonly referred to as ranging or range errors. The question is what is the relationship between the range error and the error in computed position. Or, in other words, how many meters of error are introduced in our computed position as a result of one meter of error in measuring distances to the satellites?

The answer is that it depends on the number and the geometry of the satellites used. If four satellites are clustered near each other, then one meter of error in measuring distance may result in tens or hundreds of meters of error in position. But if many satellites are scattered around the sky, then the position error may be less than 1.5 meters for every meter of error in measuring distances. The effect of the geometry of the satellites on the position error is called Geometric Dilution Of Precision (GDOP), which can roughly be interpreted as the ratio of the position error to the range error.

Imagine the tetrahedron that is formed by lines connecting the receiver to each satellite used. The larger the volume of this tetrahedron, the smaller (better) the GDOP. In most cases, the larger the number of satellites the smaller the GDOP.

Selective Availability: The Man-Made Errors

Errors in the satellite clock, the satellite orbit, the ionosphere, the troposphere, the multipath, and the receiver typically amount to less than 10 meters of range error which, under typical GDOPs of about 2, results in a position accuracy of about 20 meters.

The US Department Of Defense has determined that providing this level of precision to the general public is against the US national interest. Therefore, DOD has introduced man-made intentional errors to degrade the position accuracy of GPS to about 100 meters. This intentional degradation is called Selective Availability (SA) and is implemented by tethering the satellite clocks and reporting the orbit of the satellites inaccurately. Military receivers are equipped with special hardware and codes that can mitigate the effect of SA. SA can be turned ON or OFF through ground commands by the GPS system administrators.

Summary

In this chapter, we learned:

We can adjust the receiver time to the accuracy of the GPS clock. This will make the inexpensive clock of the receiver as good as an atomic clock.

Four is the minimum number of satellites that we need to compute position and time. (But the more satellites we have the more accurate results we can get.)

Dual frequency receivers practically remove the ionosphere effects.

If the signal indirect path is considerably longer than the direct path, more than 10 meters, then the multipath effect can be substantially reduced by signal processing techniques.

WorldChanging: Another World Is Here: What's Next for Google Earth Mashups?

Okay, I admit it: I've become a bit enamored of Google Earth. It's fun to play with, sure, but the real reason is how well it illustrates big concepts. Avian flu progress and monitoring of polar environmental conditions are just two compelling WorldChanging-relevant examples of what can be done with the Google Earth application and networked access to structured data; additional WC-type examples that popped up this week include an overlay showing global fire data from NASA's Earth Observing Satellite network, and an overlay showing South American trade from the UN Comtrade database.

So what's next? Or, rather, what would we want to be next? What kinds of information about the planet, or human activity on the planet, would be enhanced by a digital world display? The ability of Google Earth to display multiple overlays at the same time -- the key information difference between Google Earth and the satellite view in Google Maps -- suggests that we might want to start thinking in terms of combinations. What pieces of global information would you find useful to compare & contrast?

Posted by Jamais Cascio at January 27, 2006 02:39 PM | TrackBack

ArcWeb Services | ArcWeb Explorer

ArcWeb Explorer is a Web-based map viewing application based on Macromedia Flash 8. The ArcWeb Explorer uses vector mapping technology to render maps quickly in the browser instead of having the server render them. The result is improved speed and performance, greater control over the map appearance, and desktop-like functionality over the Internet.

In addition, ArcWeb Explorer provides access to ArcWeb Services so you can easily find locations by street address, telephone number (land line), and IP address. You can also create a route and directions between locations and map locations from Excel spreadsheets.

O'Reilly: "Google Maps is the new open source."

At the SD Forum in Santa Clara, California Mr. O'Reilly, Sun Microsystems' Simon Phipps and IBM's Rod Smith participated in a panel on open source. First off, the three apparently refused to narrow the definition of open source (The Register), giving a sort of "it means whatever you think it means." For example, anyone who uses Apache, they argued, is part of the open source community. That of course would include Microsoft which is oft reported to use open source technology in dribs and drabs in its empire. (Now, who would want to be part of a club that included Microsoft? Groucho would have a field day!)

More relevant to the geospatial world was the O'Reilly's statement, "Google Maps is the new open source," which followed the suggestion that Google is a great example of an open source company because it uses vast Linux server farms to build and deliver software services to customers. The writer at the Register felt O'Reilly was referring to Google's "more open" interface allowing more users to create mashups than on Yahoo's or Microsoft's platforms.

If publishing an interface is all it takes to be open source than I'll offer that Mr. O'Reilly did indeed redefine open source, or at least the "new open source."

Serious Web Map Application, or Mere Mashup - Semantics
ws.co

Let's be clear or let's debate. Do you think the term "mashup" implies a semi-serious, homegrown, just for fun app...or something for commercial use (See definition). We've been cautioned via a letter to the editor and other communication that either the term "mashup" is misunderstood entirely or that it connotes an application that's "not ready for prime time." There is a reason to consider the semantics here and be concerned with its usage. It goes directly to the issue of licensing. When the Google Maps API was first offered (or soon thereafter), there were constraints to what you could do with your mashup. The API was open; you just couldn't make money with it. Microsoft's Virtual Earth API was structured differently and written to allow broader usage for commercial applications. But while "mashup" has entered the vernacular, it may be ill-suited to describe some excellent applications with "serious" money-making opportunities...Craigslist being only one example. What's your take?

Smartphones Know Ups And Downs

rosoft and Linux lead a smartphone market that grew more than 70 percent in 2005. But, according to In-Stat, tempering the good news is word that consumers aren't doing much with the phones once they pull them out of the box.

While the smartphone market is expected to grow over the next few years, the expansion comes at a price for two familiar companies, according to Bill Hughes, In-Stat analyst.

"The market's growth will involve major shifts in share among the OS platforms," Hughes said in a statement.

Microsoft and Linux will take the lead as Blackberry maker Research in Motion (RIM) and PalmSource slow down. And while PalmSource and RIM recede, they will still experience growth, according to Hughes.

Microsoft leads at a time when the industry could use the software maker's ability to sell.

"Right now there isn't a sales channel for smartphones," according to the analyst. Microsoft has been "very successful at creating an ecosystem for smartphones," he added.

"Microsoft has taken a lot of effort developing the phone first," said JupiterResearch analyst Michael Gartenberg on the software giant's smartphone tactics. (JupiterResearch and internetnews.com are owned by Jupitermedia.)

And then there is Palm's transition to Windows Mobile.

Palm, which once used the PalmOS developed by PalmSource, has adopted Windows Mobile. Last year, Japanese software developer Access bought PalmSource.

"Palm's Treo 700 represents the best implementation of Windows Mobile," Gartenberg said. Balancing phone and data, the smartphone "serves both masters well."

The challenge to this positive growth, however, is a perplexing trend Hughes discovered: a lack of interest in upgrading.

"They look slick, but many people who own them still have other devices," Hughes said.

Smartphones are marketed as replacements for your cell phone and PDA. But Hughes found that smartphone users have twice the number of cell phones and PDAs than non-smartphone owners do.

Another aspect holding back smartphone adoption is the lack of interest in enhancing the smartphones. On average, consumers download only one new application even though the devices can handle many more.

The Windows platform could make it easier to increase the number of smartphone applications downloaded, according to Hughes. Another step: more companies offering employees smartphone applications. Currently, companies have expressed only a "lukewarm response" to such a measure, Hughes said.

Both consumers and the industry are unable to settle on a definition for a smartphone, he added. The Treo, which has both data and phone, is alternately described as a smartphone and a handset, according to which carrier you ask.

RIM, also hurt by Microsoft's ascension in the smartphone market, has been successful because it limited the device to data-only. "Less can often be more," Gartenberg said.

Reprinted from internetnews.co

Navicore adds dynamic navigation

Navicore announced Wednesday the UK availability of Navicore Personal 2006/1, the latest version of its GPS package, which enables consumers to turn their Symbian-based mobile phones into a full satellite navigation system.

The new release adds useful enhancements including the following the latest UK maps from Tele Atlas with improved graphics, new points of interest added, along with higher map resolution; full 7 digit UK postal code now support; traffic information updates provided free via GPRS offering dynamic routing thereby keeping drivers out of traffic jams as they happen.

Navicore uses traffic information data provided by iTIS Holdings Plc, one of the UK’s premier providers of traffic information and vehicle security services. iTIS collects traffic information from “floating” vehicles, automatic data collection systems, highway agencies, the AA, police and emergency services.

The application also includes safety camera downloads and updates for free via GPRS1 at user specified times; and support for addresses stored in your phone’s PIM (personal information management) makes it simple to navigate to friends, colleagues and family at the click of a button, without having to re-key in address information.

Navicore Personal 2006/1 is sold as a complete retail package containing everything necessary to start navigating straight away. The following is included in the box:

Navicore Personal 2006/1 UK was launched for Symbian Series 60 handsets. European map availability, along with additional operating system support for namely Symbian Series 80 and UIQ will be announced in Q1 2006.

The recommended retail price for Navicore Personal 2006/1 is GBP 200 for Symbian Series 60 handsets, which has been kept the same as the previous version.

Related News

* Navicore selected as the incubator business of 2005

Desire To Personalize Smartphones Expected To Drive Sales

The use of advanced cellular phones capable of running applications is expected to grow strongly over the next several years, as consumers look for devices that they can personalize to reflect who they are, a market research firm said Tuesday.

Based on the number of operating-system licenses sold, 31.5 million so-called "smartphones" were sold globally in 2005, a 70 percent increase over the 18 million the year before, In-Stat said. The 2005 number accounted for between 8 percent and 15 percent of the total number of mobile phones shipped.

The Symbian OS, which is popular in Europe, was in the largest number of smartphones shipped. Other operating systems considered by In-Stat were the Palm OS, Research In Motion's Blackberry OS, Microsoft's Windows Mobile, Linux and the HipTop OS from Danger Inc.

By 2009, smartphone shipments are expected to increase nearly fourfold to 115 million, In-Stat said.

Smartphones are gaining traction among businesses, which see the devices as enhancing productivity, particularly among sales staff and other remote workers, In-Stat analyst Bill Hughes. IT departments customize the phones for accessing email and corporate documents and forms.

The RIM Blackberrry device is an example of a popular business tool, but smartphone use in general is expected to increase in companies.

On the consumer side, which is the largest market, vanity is expected to open the door to savvy marketing by manufacturers.

"The basic trend I see in mobile phones is wanting the device to become more of a reflection of who you are," Hughes said. "Customizing the phone is very personal and represents who I am. The smartphone offers greater ability at personalization."

In addition, people "have a natural desire to want to have fewer devices," Huhes said, and the smartphone's multiple capabilities can accomplish that.

Nevertheless, manufacturers will need to provide phones with core applications that people want, and sell customers on how downloading software can create the personalization they seek.

Currently, about two thirds of smartphone users have downloaded either zero or one application, Hughes said. Also, any smartphone will have to have solid voice communications, since that remains the number one use of mobile phones, in general.

Among operating-system makers, Symbian has taken the broadest approach, working with handset manufacturers to build phones with applications targeting a specific audience, such as a salesperson or someone working for a police or fire department, Hughes said.

The other OS makers, in general, are more widely known for specific applications: Blackberry for email, Microsoft for Office productivity software and Palm for personal information management, Hughes said. Symbian, therefore, has managed to spread its use among more different groups of people.

Besides studying OS shipments, the In-Stat smartphone report included a Web survey in October of more than 1,000 consumers, including 180 with smartphones.
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Based on the number of operating-system licenses sold, 31.5 million so-called "smartphones" were sold globally in 2005, a 70 percent increase over the 18 million the year before, In-Stat said. The 2005 number accounted for between 8 percent and 15 percent of the total number of mobile phones shipped.

The Symbian OS, which is popular in Europe, was in the largest number of smartphones shipped. Other operating systems considered by In-Stat were the Palm OS, Research In Motion's Blackberry OS, Microsoft's Windows Mobile, Linux and the HipTop OS from Danger Inc.

By 2009, smartphone shipments are expected to increase nearly fourfold to 115 million, In-Stat said.

Smartphones are gaining traction among businesses, which see the devices as enhancing productivity, particularly among sales staff and other remote workers, In-Stat analyst Bill Hughes. IT departments customize the phones for accessing email and corporate documents and forms.

The RIM Blackberrry device is an example of a popular business tool, but smartphone use in general is expected to increase in companies.

On the consumer side, which is the largest market, vanity is expected to open the door to savvy marketing by manufacturers.

"The basic trend I see in mobile phones is wanting the device to become more of a reflection of who you are," Hughes said. "Customizing the phone is very personal and represents who I am. The smartphone offers greater ability at personalization."

In addition, people "have a natural desire to want to have fewer devices," Huhes said, and the smartphone's multiple capabilities can accomplish that.

Nevertheless, manufacturers will need to provide phones with core applications that people want, and sell customers on how downloading software can create the personalization they seek.

Currently, about two thirds of smartphone users have downloaded either zero or one application, Hughes said. Also, any smartphone will have to have solid voice communications, since that remains the number one use of mobile phones, in general.

Among operating-system makers, Symbian has taken the broadest approach, working with handset manufacturers to build phones with applications targeting a specific audience, such as a salesperson or someone working for a police or fire department, Hughes said.

The other OS makers, in general, are more widely known for specific applications: Blackberry for email, Microsoft for Office productivity software and Palm for personal information management, Hughes said. Symbian, therefore, has managed to spread its use among more different groups of people.

Besides studying OS shipments, the In-Stat smartphone report included a Web survey in October of more than 1,000 consumers, including 180 with smartphones.

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Print This Story
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The Best in Mobile, 2005 at MobHappy

Following The Worst In Mobile, 2005 that I wrote a few weeks back, it seemed proper to follow it up with the best of the year in the mobile industry, so here goes:

- 3 UK’s Gareth Jones Moves On: You probably best remember Jones, 3’s COO, as the guy that told New Media Age “People don’t want open access, that’s not what our customers tell us they want. Anyone in their right mind who tries to do anything on the Internet with a screen that size has to be nuts.” So anybody that wants to do stuff on their phone other than exactly what their operator has authorized is crazy — yeah, we’re really sad to see you go, Gareth. Don’t let the door hit you, etc etc.

- Opera Mini: Opera Mini is the best J2ME application I’ve ever seen. It’s a highly competent HTML browser that runs beautifully, and works better than pretty much every native browser I’ve seen on non-smartphone handsets. It renders complicated pages well, and works pretty quickly, even on my GPRS connection. It really is quite a big deal, as it can bring an easy, well-rendered mobile browsing experience to mid-range and low-end devices. Incidentally, it’s now freely available to all users, regardless of where they live. Of course, ol’ Gareth probably isn’t impressed by this, and it’s just furthering his opinion that I’m craaaazy.

- the Sony Ericsson K750i: Both Russell and I’s pick, the K750 is a fabulous device. I switched to it after a succession of smartphones, and I don’t miss them at all. Physically, it’s a great size and is well-designed. The screen is bright and sharp; its autofocus 2-megapixel camera takes excellent photos. The UI, though, really shines, blowing away the interfaces of similar phones from other manufacturers (particularly Nokia’s Series 40, which is really showing its age these days). An added bonus — the K750 survived being dropped and submerged in water unscathed.

- Yahoo and Google start paying some real attention to mobile: 2005 was notable in one regard, as the search giants began a real mobile effort with things like Yahoo’s nice, powerful SMS search and Google Local Mobile, a sweet little J2ME app. With the way things have played out so far in 2006 — both with Google and with Yahoo Go — makes me think it should be even more interesting.

- Mobloggers force O2 rethink: Alfie Dennen and his posse from moblogUK got O2 to quit sending MMS as links to Web pages when they were sent to email addresses, effectively preventing people from using any outside moblogging or image-hosting service. Of course, O2 had a moblog service it offered alongside Kodak that worked just fine (for a while anyway). Good year for Alfie and the moblogUK crew, given this and their prominence in the cameraphone coverage of the London bombings.