[Click] Fwd: RSSI values from click

[Robert Owen]

I might have sent it to a wrong address.
My apologies if I'm flooding the list with another copy.

---------- Forwarded message ----------
From: Robert Owen <robyowen at gmail.com>
Date: Jul 6, 2006 5:22 PM
Subject: RSSI values from click
To: click at pdos.csail.mit.edu

Hi there,

I hope it's not off the topic of this list.
I did some RSSI measurements using click, and found that the RSSI values
almost do not change if the transmission power exceeds a certain threshold.
This seems to be contrary to what one would expect.

Here are the experiment setup and results:
I have two nodes, about 6-7 feet apart, one broadcasting and the other
receiving.
The sender broadcasts 1000 packets with 1 second interval.

tx power (mW)          1         5         10        20         30
40        50        60
mean RSSI       23.314  23.331  25.686  32.149  35.778  35.758  35.733
35.693

Initially, there's only slight RSSI increase with txpower from 1mW to 5mW.
Then it seems to be normal with txpower from 5mW to 30mW.
But from 30mW on, RSSI almost does not change.

I wonder if somebody out there did similar RSSI measurements using click.
Is it possible that the increase from 30mW on does not take effect at all?

Thank you!