Thanks, I agree that for most environments specifying a fixed channel is sufficient.
The problem is we're creating a product that could be installed in any number of environments (apartment buildings for example), where we have no control over what interference may be present. To avoid denial of service (intentional or accidental), it would be desirable if the radios could dynamically avoid interference. It is my understanding that freq hopping will resolve this (to some degree at least), which I would need to implement in the MAC software. Why would a cheap cordless phone be smart enough to avoid the mote channel, but the mote is not smart enough to avoid the cordless phone? :) >From the CC2420 Datasheet, page 58 section 34.1 "With CC2420 it is also possible to combine both DSSS and FHSS in a proprietary non-IEEE 802.15.4 system." Cheers, Matt Thompson Michael Schippling wrote: >> Umm...why is chan 26 not a permanent solution? >> >> Anyway, IMHO as they say, you just have to find a setting that doesn't >> interfere in your environment. The contrib\xbow\apps\MakeXbowlocal >> file has a list of frequencies and recommendations for 802.11 avoidance. >> If your phone is FHopping I would think it would be smart enough to >> avoid the tmote channel, so maybe it is set to a single freq? >> >> not much help, I know. >> MS >> >> >> >> Matt Thompson wrote: >> > > >>>> Hi, >>>> >>>> I was wondering if anyone has experienced this, and/or knows a >>>> resolution. >>>> >>>> When I turn on a GE 2.4GHz Analog cordless phone, there is absolutely no >>>> communication between two Tmote sky modules (CC2420 Radio). 802.11 does >>>> not seem to interfere, nor does a set of old Radio Shack 2.4GHz wireless >>>> video senders, although I have not yet tried all channels. I can avoid >>>> the cordless phone interference by using channel 26 on the motes, but >>>> this is not a permanent solution. >>>> >>>> It seems the only way to resolve this would be to implement FHSS >>>> (Frequency Hopping). Is this correct? >>>> >>>> Cheers, >>>> Matt Thompson >>>> Lochisle Inc. >>>> _______________________________________________ >>>> Tinyos-help mailing list >>>> [email protected] >>>> https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >>>> >> >> >> > > _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
