Mobile Network Geolocation: Obtaining the Cell IDs & the Signal Strength of Surrounding Towers From a GSM Modem & Triangulating Device Location

Mobile Network GeolocationTo perform basic triangulation of the client GSM device’s location, the GSM modem can be queried to return information about the towers in the area, including their unique Cell Ids, and the signal strength obtained from each.

Using this information, a circle can be drawn around each cell, with the circle size relative to the signal strength of each tower. The point where these circles intersect can be considered the client’s probable location.

Here we explore methods of communication with an internal GSM modem over a serial interface, some of the applicable Hayes or AT commands used to communicate with the hardware and how the information provided to us buy the modem can be used to determine the device’s location by triangulating it’s position against known cell tower locations.

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Creating an HTML5 Paint App

HTML5 Paint App
There are several apps available today that allow one to draw freely on your touch screen smartphone. Be it to take notes, annotate photographs, capture signatures digitally or to play games like the popular OMGPOP Draw Something App.

In this article we’ll explore a way to achieve this using the HTML5 canvas element and a little JavaScript.

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