Dear Jobish John. You know the reason about why the measure of the Rssi in the Base is -3dBm, because after make a link budget calculus it should be: 10 dBm when the two antennas are touching?
Ptx+GainTx+GainRx= 0dBm+5dBi+5dBi= 10dBm Nevertheless the currently value obtained is -3dBm (The maximum value obtained in terms of wireless power) Thanks in advance for your kind answer. Alex CP CUC. On Sat, May 9, 2015 at 2:00 PM, <[email protected] > wrote: > Send Tinyos-help mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > > or, via email, send a message with subject or body 'help' to > [email protected] > > You can reach the person managing the list at > [email protected] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Tinyos-help digest..." > > > Today's Topics: > > 1. Re: Rssi convert to dBm in TelosB (Alex Cp) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sat, 9 May 2015 12:45:00 -0500 > From: Alex Cp <[email protected]> > Subject: Re: [Tinyos-help] Rssi convert to dBm in TelosB > To: tinyos-help <[email protected]> > Cc: ketan patel <[email protected]> > Message-ID: > <CAJk1sZ= > [email protected]> > Content-Type: text/plain; charset="utf-8" > > Dear Jobish Jhon and Alexander. > > Thanks a lot for all advices. Currently are worked fine, and the best is > the fact that I know the calculus is very trustworthy (accurate information > Jobish Jhon). > > Finally the file RssiDemo.java is now: > > ... > int source = message.getSerialPacket().get_header_src(); > double rssi = msg.get_rssi()-45; > System.out.println("Rssi Message received from node " + source + > ": Rssi = " + rssi + " " + "dBm"); > } > ... > > And mantaining the two TelosB motes very, very close (touching its > antennas) I've obtained: > > Rssi Message received from node 1: Rssi = -4.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -4.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > Rssi Message received from node 1: Rssi = -3.0 dBm > > Thanks a lot again!! > > Alex CP > CUC > > > On Sat, May 9, 2015 at 2:14 AM, JOBISH JOHN <[email protected]> > wrote: > > > Hi Alex, > > > > The datasheet (Page No: 11) of CC2420 says ? The range for RSSI is > > approximately from ?100 dBm to 0 dBm ?. Page No: 49 of CC2420 datasheet > > talks about substracting the offset value, -45 to get the dBm equivalent. > > Page No: 10 of datasheet talks about the Receiver Sensitivity (Typ: -95 > > dBm). > > > > Your previous readings shows approx. 0 dBm (when both the motes placed > > very close) > > > > Try to increase the distance between the motes. When they get > > disconnected, the Rssi Message received on your PC will be close to -50 ( > > so that -50 -45 = -95dBm) ( I am getting this value). > > > > Thus I believe subtracting -45 is enough. > > > > Thanks > > > > Jobish John > > > > > > > > > > > > On Sat, May 9, 2015 at 10:37 AM, Alex Cp <[email protected]> wrote: > > > >> Hi all. > >> > >> Im trying to convert in dBm the values obtained from the app: > >> > >> <http://tinyos.stanford.edu/tinyos-wiki/index.php/Rssi_Demo> > >> > >> In my case appears the next values: > >> > >> Rssi Message received from node 1: Rssi = 40 > >> Rssi Message received from node 1: Rssi = 41 > >> Rssi Message received from node 1: Rssi = 40 > >> Rssi Message received from node 1: Rssi = 40 > >> Rssi Message received from node 1: Rssi = 41 > >> > >> Because is very close both motes TelosB (Sending Mote and Rssi Base ) > >> > >> In the TinyOS tutorial appears the next: "...that this app prints only > >> the raw RSSI values ..." > >> > >> On the other hand I have the Data sheet of the RF Transceiver CC2420: > >> > >> <http://web.stanford.edu/class/cs244e/papers/cc2420.pdf> > >> > >> But is not clear to me How I can do the conversion from raw RSSI to dBm. > >> > >> > >> I read, someone in the TinyOS mail-list, who wrote that is only > necessary > >> substract -45: > >> > >> < > >> > https://www.millennium.berkeley.edu/pipermail/tinyos-help/2014-March/058162.html > >> > > >> > >> But I suppose is not a exact calculation. > >> > >> I'll be grateful if somebody can generously explain how is the correct > >> way to convert raw RSSI values from a TelosB to a dBm. > >> > >> Thanks in advance. > >> > >> Alex. > >> > >> > >> Date: Mon, 3 Mar 2014 12:13:27 +0530 > >> From: ashok <[email protected]> > >> Subject: [Tinyos-help] RSSI DEMO > >> To: [email protected] > >> Message-ID: > >> <CAKs3p-d4GxW_dJjVc9Hwmk-+X_ZKi+hnvzCr+C2TS2NkuKg4uA@mail. > >> gmail.com> > >> Content-Type: text/plain; charset="iso-8859-1" > >> > >> Dear All, > >> > >> I am getting RSSI value in tinyos like: > >> > >> Rssi Message received from node 1: Rssi = -14 > >> Rssi Message received from node 1: Rssi = -1 > >> Rssi Message received from node 1: Rssi = 2 > >> Rssi Message received from node 1: Rssi = -2 > >> Rssi Message received from node 1: Rssi = 2 > >> Rssi Message received from node 1: Rssi = 0 > >> Rssi Message received from node 1: Rssi = -2 > >> Rssi Message received from node 1: Rssi = 2 > >> Rssi Message received from node 1: Rssi = 2 > >> > >> and I want to conform that is this value is in Dbm? > >> > >> if not than how can i convert it? > >> > >> regards, > >> > >> -ashok > >> > >> _______________________________________________ > >> Tinyos-help mailing list > >> [email protected] > >> > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > >> > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > https://www.millennium.berkeley.edu/pipermail/tinyos-help/attachments/20150509/3814e7ec/attachment-0001.htm > > ------------------------------ > > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > > End of Tinyos-help Digest, Vol 145, Issue 8 > ******************************************* >
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