Re: [Discuss-gnuradio] Power line communications

[Johnathan Corgan]

On Mon, Feb 20, 2012 at 07:32, Johnathan Corgan
<address@hidden> wrote:

>> If you ever do this again, I would love to see some of the channels over
>> time.  I ordered some basic PLC equipment, but all I really have access to
>> are packets :P
>
> I'll try to grab a spectrum analyzer plot from my lab.

Below are two images of the RF spectrum as received through a power
coupler plugged into a wall socket in my office building.

The first is DC-500MHz:

http://gnuradio.org/data/power-line-500MHz.jpg

The green line is the thermal noise floor in the RF bandwidth used
(the measurement setup has a NF of about 9dB).

There are no quiet parts of the spectrum, and many narrowband signals.
 FM radio stations are obvious around 100 MHz.

The 125MHz spectral line and 100 MHz harmonics go away when I unplug a
USRP N210 on the same power strip :-)

A zoom of the first 50 MHz:

http://gnuradio.org/data/power-line-50MHz.jpg

It's pretty noisy all over.

Johnathan