Location based services

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UNDERSTANDING LOCATION BASED SERVICES FOR MOBILE APPLICATIONS

There are a whole lot of benefits possible around location based services on mobile phones. Before we go on to understand sample of such services and the benefits let’s first understand how the location of a mobile device is detected.

Currently, there are two ways in which location of the mobile phone is established:

A-GPS vs GPS

GPS stands for Global Positioning System. Standalone/autonomous GPS operation uses radio signals from satellites, therefore, a GPS device communicates with 4 or more satellites to determine its exact location coordinates (latitude and longitude) anywhere on Earth. It works in any weather as long as the device has a clear line of sight to the satellites.

A-GPS stands for assisted global positioning system, while just regular GPS is non-assisted.

GPS satellites circle the earth twice a day in an orbit. These satellites continuously send information to the earth via radio waves. Messages transmitted by the satellites include (a) the time the message was transmitted, (b) the ephemeris or the information about the orbit, and (c) the almanac or the health and rough orbits of all the satellites. GPS receivers use these signals by calculating the time at which the signals were sent by the satellites and time at which they were received on Earth. Once the GPS receiver knows the position of at least four satellites and the transmit time of each (this is called time to first fix, TTFF), it is able to lock its own location.

This method of computing is called trilateration. This initial TTFF is often called a cold start, it can take anywhere from 30 seconds to a couple of minutes to acquire a signal. That time is dependent on ones’ location, amount of interference and horizon information; for example open fields are faster than urban environments where hi-rise buildings can interfere with the satellite-receiver line of site. The data rate of the satellite signal is only 50 bit/s, so downloading orbital information like ephemeris and almanac directly from satellites typically takes a long time, and if the satellite signals are lost during the acquisition of this information, it is discarded and the standalone system has to start from scratch.

A-GPS additionally uses network resources to locate and use the satellites in poor signal

conditions, making the whole process is much faster. Very often cellular network towers have GPS receivers (or a base station nearby) and those receivers are constantly pulling down satellite information and computing the data. This data is then passed on to the cellular phone (when requested) and acts like a cheat since the relevant satellites to your location are already identified and all that GPS computations is handled by 3rd party computers. This is the result of such a system, to you the end user:

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Faster location acquisition Less processing power is required by the device Saves battery life Location acquisition indoors or in non-optimal environmental settings.

In A-GPS, the Network Operator deploys an A-GPS server. These AGPS servers download the orbital information from the satellite and store it in the database. An A-GPS capable device can connect to these servers and download this information using Mobile Network radio bearers such as GSM, CDMA, WCDMA, and LTE or even using other wireless radio bearers such as Wi-Fi. Usually the data rate of these bearers is high; hence downloading orbital information takes less time.

A pictorial representation of GPS and A-GPS is shown below.





Summary of comparison between A-GPS and GPS is like this:

A-GPS GPS

Stands for

Assisted Global Positioning System Global Positioning System

Source of triangulation information

Radio signals from satellites and assistance servers e.g. mobile network cell sites

Radio signals from GPS satellites

Speed

A-GPS devices determine location coordinates faster because they have better connectivity with cell sites than directly with satellites.

GPS devices may take several minutes to determine their location because it takes longer to establish connectivity with 4 satellites.

Reliability

Location determined via A-GPS are slightly less accurate than GPS

GPS devices can determine location coordinates to within 1 meter accuracy

Cost

It costs money to use A-GPS devices on an ongoing basis because they use mobile network resources.

GPS devices communicate directly with satellites for free. There is no cost of operation once the device is paid for.

Usage

Mobile phones Cars, planes, ships/boats





LOCATION BASED SERVICES

Location based services are simply those applications that make use of the availability of the location of a mobile phone (thus user) innovatively for businesses. There are a whole lot of possibilities which could be built on the basis of availability of the location related of the users. The largest platform that makes use of location of users is of course Four Square but it is more social in nature.

We, at Saral Technomart, have built innovative application catering to the employees working in the field or on-site. The reporting from remote teams is a difficult proposition and almost all companies struggle with the issue. The reporting is mainly relied on the telephonic and/or email communication from these people to their respective reporting heads positioned in office. This kind of reporting is mostly not very authentic and some percentage of goof-up is assumed in this process, wherein the percentage will vary from person to person.

Our latest solution, Nimboli, the field force management solution enables employees to report directly from their mobile phones which can be substantiated with photos, audio or video recording in real-time. The category of the employee could be sales or service or any other profile. This, not only improves the speed of flow of information, but also increases authenticity since this information comes along with the location related details of the user pushing this information.

Similarly, dynamic information (lying in the company servers) can be pushed to the mobile phones of the field staff which could drastically improve their productivity. The solution can also be used for market intelligence or checking the progress of any work or activity at a remote site.

For details, check www.nimboli.in or call on 8800267070


http://www.nimboli.in/

Technology

Location based services