Hello,

the RSSI value can be obtained by using

newRSSi = (int8_t)(call CC2420Packet.getRssi(mess) - 45);

in this way you obtain a negative value between ~ -100 (weak signal) and ~
-25 (strong signal)
I do not exactly remember the range, however the value must be in the first
100 negative numbers.

Hope this helps,
Marco

On 13 September 2011 08:02, Xiaowei <[email protected]> wrote:

> Hi all,
>
> I'm doing some experiments to measure the Rssi value of the telosb motes in
> TinyOS. I did this by sending blank packet to base station and calling
> the CC2420Packet.getRssi(msg) command in the receive() method of Base
> Station and storing the returned value in the packet. Then I get the value
> in raw packet with java Listen tool. I measured Rssi from different
> distances and the value I get is either around 0 or 65500.
>
> Am I measuring Rssi correctly in this way? Is the raw value I get from the
> packets the real Rssi value?
> I know the value could be influenced by the environment, but could it also
> be influenced by some default packets (although I didn't set anything on
> sender mote, just sending some blank packets) ?
>
> Anyway, what I want to verify is  whether the Rssi value of a sensor mote
> measured by a Base Station from different distance stable enough to
> distinguish it from others?
>
> Appreciate if you have any comments or ideas.
> Thanks in advance!
>
>
> -Sean
>
> _______________________________________________
> Tinyos-help mailing list
> [email protected]
> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
>
_______________________________________________
Tinyos-help mailing list
[email protected]
https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help

Reply via email to