USRP1 and WBX, communication distance

GNU Radio
1

Hi,

I would like to ask you a question regarding the USRP1 and WBX. Have
anybody
made some tests withthese and other ISM band transceivers to see the
communication distance indoor and outdoor? For example if I have a
tranceiver on
433MHz and it has a transmission power of 17dBm, which should be the
minimum
distance in open air to be able to receive data packets sent from the
USRP1+WBX+LP0410, (what about indoor - it depends from nr. of walls and
thickness but anyway I would like to know your opinion, and your
experience with
this)? Right now I’m trying to make the packet
()with the help of functions from Gnuradio, and it’s
quite
difficult, and then to make FSK modulation and send it to my
transceiver. In
documentation for the USRP1 the transmission power is between 50mW - 100
mW
(17-20dBm)? For my transceiver that has 17dBm transmission power says
that it
can transmitt data as far as 800m outdoors, would it apply to USRP1,
too?
Indoors the transceivers works quite well, I can senddatafrom one module
to
other in my whole house, the distance is around 15m, through walls (max.
3 walls
between transceivers). Anybody tried to do such kind of things, and has
arived
to any results?

I would appriciate any comment on this.

Thank you very much,
Gunther.

2

On 04/19/2011 05:44 PM, Gunther Ferdinand wrote:

LENGTH>) with the help of functions from Gnuradio, and it’s
Thank you very much,
Gunther.
Answering that question requires a lot of “it depends”.

Maximum transmission distance is proportional to a number of parameters:

 o transmit power (or more precisely effective radiated power

towards the receiver)
o receiver sensitivity–which depends both on noise figure of the
receiver, and directivity of the receive antenna
o any impairments to the signal due to physical obstructions,
causing absorption and multi-path reflections
o bandwidth of the signal
o modulation scheme
o processing gain due to coding techniques, etc

So, you see, a complete model is quite complicated, so answering the
question without “fleshing out the model” is not really possible.

Can you communicate beyond the edge of your desk? Yes, almost
certainly. Beyond the edge of your living room? Probably? Beyond the
edge of your city block? Not sure.