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Showing posts from March, 2016

Getting started with Programming ESP8266- ESP07 modules

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 Recently I had to use esp8266 modules to do my research on wifi radio tomography. To program them was a challenge because of my lack of knowledge in electronics. It was very new to me and I got a huge support from my research supervisor and research lab friends to do this. Below are the steps I followed and reference I used to understand and program.   Specifications: Linux Ubuntu version 14.04 Arduino 1.6.8 Steps to follow: 1. Download and install Arduino To install and start with Arduino on linux, this is good link->  arduino 2. Start the arduino IDE. Open 'preferences' from file menu. Enter this text/link in the field -> http://arduino.esp8266.com/stable/package_esp8266com_index.json 3. Open 'board manager' from Tools->Board menu and search for esp8266 platform. Install it. 4. Select "Generic ESP8266 Module" from Tools-> Board, and select the following settings. Flash Frequency: 40MHz CPU Frequency: 80MHz U

Radio Tomography Imaging

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Since I conduct research on tomography area, I thought writing a small article as an introduction to many who does not know about this. Radio Tomography Imaging (RTI) is a technique used to generate 2D images of the change in the electro-magnetic field inside the area covered by the radio transceivers to spot the presence and movements of animates (e.g., people, large animals) or large metallic objects (e.g., cars). Below are some graphs of the basic experiments I conducted to see this effect. I have plotted two plots per graph. Clear Line of  Sight (LOS) and a man standing in the middle(LOS) disturbing the link which allows us to see the difference clearly. Plot is for a single link, using many distances. Plotted graphs using matplotlib. Here is the link for the code.

Using SCP command to transfer folder from local machine to remote machine

We use SCP command to transfer/copy files/folders to remote machine to a specified location, in the following way. Execute the commands from your local machine. Copy a file: [dilushi@debian ~]$ scp examplefile yourusername@server:/home/yourusername/ Copy the whole directory, use -r option: [dilushi@debian ~]$ scp -r directoryname yourusername@server:/home/yourusername/ . Reference