LQI is in relation to how many code-bits are "good" AFAIK. For distance, even questionable RSSI readings seem more ... well, useful.
sing.stanford.edu/talks/emnets2006.ppt has some pretty graphics of LQI values. It's not too pretty. (Well, the "conclusion", and that was even from a localization perspective...) On Mon, May 12, 2008 at 9:11 AM, Dan <[EMAIL PROTECTED]> wrote: > Janos, > > Thank you so much. I did something to measure the distance by RSSI on > MICAZ and now I wanna do the same thing on IRIS. LQI seems prone to > err compared with RSSI. > > ~Dan > > On 5/12/08, Janos Sallai <[EMAIL PROTECTED]> wrote: >> Dan, >> >> Currently the rf230 stack does not support reading the RSSI. According >> to the rf230 datasheet (page 52.): "Note, it is not recommended to read >> the RSSI value when using the Extended >> Operating Mode." (the radio stack is using the extended operating mode) >> >> Depending on what you want to do, you might want to use the LQI value >> instead. Or, you can try reading the RSSI value from the register >> directly, but keep your fingers crossed... >> >> Janos >> >> -----Original Message----- >> From: [EMAIL PROTECTED] >> [mailto:[EMAIL PROTECTED] On Behalf Of Dan >> Sent: Sunday, May 11, 2008 8:14 PM >> To: tinyos-help@millennium.berkeley.edu >> Subject: Re: [Tinyos-help] How to control the radio power in iris >> platform? >> >> Thanks for your info. Actually I'm also doing the same stuff. I have >> another question: how to get RSSI value of received packets? It's easy >> to get this info for micaz(cc2420), but I can't find related functions >> in the directory RF230. Do I have to read the register directly? >> Thanks! >> >> ~Dan >> >> On 5/11/08, Janos Sallai <[EMAIL PROTECTED]> wrote: >> > >> > >> > >> > In my previous mail I meant: >> > >> > >> > >> > "If you _always_ want to send with some predefined transmit power, you >> need >> > to define the RF230_DEF_RFPOWER preprocessor variable (e.g. by adding >> > PFLAGS+=-DRF230_DEF_RFPOWER=9 to your Makefile)." >> > >> > >> > >> > Janos >> > >> > >> > >> > >> > From: [EMAIL PROTECTED] >> > [mailto:[EMAIL PROTECTED] On >> > Behalf Of Janos Sallai >> > Sent: Sunday, May 11, 2008 3:23 PM >> > To: Xiaojun Zhu; tinyos-help@millennium.berkeley.edu >> > Subject: Re: [Tinyos-help] How to control the radio power in iris >> platform? >> > >> > >> > >> > >> > Xiaojun, >> > >> > >> > >> > If you _always_ want to send with some predefined transmit power, you >> need >> > to define the RF230_DEF_RFPOWER preprocessor variable (e.g. by adding >> > -DRF230_DEF_RFPOWER=9). This defines the TX_PWR field of the >> PHY_TX_PWR >> > register. Please see pp 59-60 of the rf230 data sheet for the >> supported >> > power values (0:most power, 0xf: least power, >> > >> > http://www.atmel.com/dyn/resources/prod_documents/doc5131.pdf >> > ) >> > >> > >> > >> > Alternatively, you can set the transmit power on a per packet basis >> through >> > the PacketTransmitPower interface of DefaultPacketC. That is, you >> need to >> > set the transmit power every time before calling AMSend.send. >> > >> > >> > >> > You need to add this wiring to your configuration (assuming the module >> where >> > you set the transmit power is called MyAppC.nc): >> > >> > >> > >> > components DefaultPacketC; >> > >> > DefaultPacketC.PacketTransmitPower -> >> > MyAppC.PacketTransmitPower; >> > >> > >> > >> > Then, your module: >> > >> > >> > >> > uses interface PacketField<uint8_t> as PacketTransmitPower; >> > >> > //... >> > >> > implementation { >> > >> > //... >> > >> > call PacketTransmitPower.set(&my_message_t, /* some small >> > value here, see the rf230 datasheet*/); >> > >> > call AMSend.send(addr, &my_message_t, len); >> > >> > >> > >> > Janos >> > >> > >> > >> > >> > From: [EMAIL PROTECTED] >> > [mailto:[EMAIL PROTECTED] On >> > Behalf Of Xiaojun Zhu >> > Sent: Friday, May 09, 2008 11:46 PM >> > To: tinyos-help@millennium.berkeley.edu >> > Subject: [Tinyos-help] How to control the radio power in iris >> platform? >> > >> > >> > >> > >> > Hi all, >> > >> > >> > I want to make the mote not so powerful so that the message >> can >> > reach the destination only by multi-hop in a limited area,like in a >> room. >> > The reason is that I want to study the behavior of MULTI-HOP in my >> lab. I >> > search this list and find some one posted a question similar to this >> > without replying. Is that possible? I'm using Iris platform. >> > >> > >> > Please let me know if my expression is not so clearly. >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > Thanks, >> > >> > >> > >> > >> > >> > Regards, >> > >> > >> > Xiaojun >> > >> > >> > >> > >> > >> > >> > >> > >> > ________________________________ >> > >> > >> > Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try >> it >> > now. >> > _______________________________________________ >> > Tinyos-help mailing list >> > Tinyos-help@millennium.berkeley.edu >> > >> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >> > >> >> _______________________________________________ >> Tinyos-help mailing list >> Tinyos-help@millennium.berkeley.edu >> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >> > _______________________________________________ > Tinyos-help mailing list > Tinyos-help@millennium.berkeley.edu > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > _______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
