Re: 3G Signal CSQ

That's 1/2 a lie, they support RSSI, which is the value they return from
AT+CSQ.  RSSI is an arbitrary unit that's assumed to be linear in scale
(unlike dBm).  CSQ is defined to be 0 - 31, and internally in NM that's
normalized to a 0...100 scale.  Technically GetSignalQuality*does*
return RSSI, but may not be reported in the modem's native RSSI scale.
On some devices (Ericsson MBM) the scale is 0...5 even.

If you're looking for a much deeper RSSI, like radio diagnostic data,
then that's actually impossible to get for most devices

Very thanks for your help.

Aleksander already said me (in spanish). But with my modem seems to be a
bug with "echo", solved in next versions of NM (fedora 16 still have old

Specifically, the logs show that even if we try to disable the echo, the modem doesn't do it, so the replies to AT+CSQ and every other command come with the echo:

modem-manager[2430]:<debug> [1332115236.128042] [mm-at-serial-port.c:298] debug_log(): (ttyACM1): --> 'AT+CSQ<CR>' modem-manager[2430]:<debug> [1332115236.134616] [mm-at-serial-port.c:298] debug_log(): (ttyACM1):<-- 'AT+CSQ' modem-manager[2430]:<debug> [1332115236.136292] [mm-at-serial-port.c:298] debug_log(): (ttyACM1):<-- '<CR><CR><LF>+CSQ: 24,0<CR><LF><CR><LF>OK<CR><LF>'

Newer MM 0.5.2 comes with the built-in echo removal thingy, which should help to fix this issue.


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