Arduino Yun WiFi signal scan.

Hello, I am working on a final year project in college. A team and I are designing a small RC car that will drive around and scan WiFi signal strength. However we have run into a few issues and was wondering could anyone help us. WE have a program that scans Wifi and prints signal strength, how ever it does not work at all when it's not connected to a computer. the second problem is we need to store the signal strength in a variable for later use. Any ideas? Thanks in advance.

mccannsean421:
WE have a program that scans Wifi and prints signal strength, how ever it does not work at all when it's not connected to a computer.

Does your setup() function have this construct in it, or something that looks like it, which is common in many examples?

while (!Serial);

This waits for a USB serial connection to be made before going any further. It's handy when you want to see the initial serial output that may go by before you establish a connection, but it means that it won't ever run without a connection.

If you have that, remove it or comment it out.

the second problem is we need to store the signal strength in a variable for later use. Any ideas? Thanks in advance.

I assume you mean a list of signal strengths, not just one (because one would be trivial, and if you're a final year student asking about that you're in big trouble.)

Since the RAM in the Arduino processor is limited, you won't be able to store many samples. Look at the Bridge library's FileIO classes, which will let you log your data to an SD card. Or, if you are writing that portion on the Linux side of things, saving the data in a file is even easier. I would suggest saving the data as a comma delimited text file that can be read directly into a spreadsheet for further analysis.

Install PIP for Python

http://forum.arduino.cc/index.php?topic=244536.msg1751021#msg1751021

Parse the output of iwlist scan to get the name, address, quality, channel, and encryption type of all networks broadcasting within Yun Wireless NIC's reach.

Name             Address             Quality   Channel   Encryption
wireless1        20:AA:4B:34:2C:F5   100 %     11        WEP
wireless2        00:26:F2:1E:FC:03    84 %     1         WPA v.1
wireless3        00:1D:D3:6A:3C:60    66 %     6         WEP
wireless4        20:10:7A:E5:02:98    64 %     1         WEP
wireless5        CC:A4:62:B7:D2:B0    54 %     8         WPA v.1
wireless6        30:46:9A:53:3C:76    47 %     11        WPA v.1
wireless7        A0:21:B7:5F:84:B0    44 %     11        WEP
wireless8        04:A1:51:18:E8:E0    41 %     6         WPA v.1

Insert WiFi signal data into SQLite

http://forum.arduino.cc/index.php?topic=261296.msg1844386#msg1844386

Schedule Tasks on Linux Using Crontab

Add GPS data as enhancement, insert them with WiFi signal data.

http://forum.arduino.cc/index.php?topic=208117.msg1533957#msg1533957

Setup PRIMARY KEY and automatic timestamp in SQLite

Use Google Map draw the route.

I'm a newbie, I following your step by step get wifi signal scan but i don't know how can I get data from IW_Parse to parameter and insert to DB

Thank you