I used the CC2420Config interface for switching channels in my application. According to the comment in the interface file, the setChannel interface can be used to set channel from 11 through 26. But in my test, I found that the pair of micaz nodes that I used were able to communicate even when they used channels from 0 to 10 (in addition to 11 to 26) .
So what are all the valid channels we can use for micaz motes? ------Original Message------ From: Omprakash Gnawali Sender: [email protected] To: Sudha Krishna Cc: [email protected] Subject: Re: [Tinyos-help] rssi measurements using Micaz Sent: May 14, 2009 12:10 AM On Wed, May 13, 2009 at 5:51 PM, Sudha Krishna <[email protected]> wrote: > Hi, > > We are doing some localization expts for which we are collecting RSSI > values using the Xbow micaz motes. We use a transmitter and receiver, > with their power level set to 31 (0dBm) using the TinyOS makefile > (CC2420_DEF_RFPOWER=31). We are essentially using the RssiDemo code > with an additional field in the beacon message. I have attached a plot > that displays the RSSI values (y-axis, in dBm) taken at different > distances (X-axis in feet) in a free space outside environment. The > distances are [6,9,12,15,12,18,21,24,30,36]ft. We subtract -45 from > the raw RSSI values output by the RSSIdemo code to get the value in > dBm. Both the motes are in line of sight and placed well above ground > level and there is no other known source of interference. > > Generally the RSSI values are supposed to decrease with distance and > follow a log-linear path loss model. Strangely, as you can see from > the plot after some distance the RSSI values are higher. We are unable > to explain this behaviour, especially given that the multipath effect > is minimal in free space. We are not sure if this an artifact of the > micaz mote hardware or the CC2420 radio or something else we have > overlooked in the software. Has anyone else observed this behaviour > with micaz motes? If someone has an idea why this may be occurring > and how to fix this problem, we would be interested in knowing. You might want to look at figure 5 on Joe Polastre's paper: http://www.polastre.com/papers/spots05-telos.pdf - om_p Sent via BlackBerry by AT&T _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
