-32763.0 dBm

Aleksander Morgado aleksander at lanedo.com
Thu Sep 27 08:05:09 PDT 2012


>>>>> Your output with Get Signal Strength was before:
>>>>>
>>>>> ECIO:
>>>>>         Network 'umts': '-126.0 dBm'
>>>>>
>>>>> That was given from a raw read value of '252' treated as unsigned. If we
>>>>> treat that value as signed we would get '-4', which multiplied by (-0.5)
>>>>> gives us +2dBm.
>>>>
>>>> Which takes us to the next issue, which is that EcIo is not supposed to
>>>> be positive as you usually have more interference/noise than signal
>>>> energy...
>>>
>>> Really? Well, anyway, the last patch seems to give consistent readings:
>>>
>>
>> I pushed the fix now; if someone wants to investigate a bit more
>> regarding the reported Ec/Io values it would be great.
> 
> EC/IO given in dBm should actually be always negative; values of less
> less than 3 (ie, -2 or -1 which would be really, really good signal)
> typically aren't seen since they're so good, just like you never get a
> WiFi signal better than -20 dBm.
> 
> Quick overview:
> 
> http://www.telecomhall.com/what-is-ecio-and-ebno.aspx
> 

Can anyone else check the reported Ec/Io values with other modems? I'm
still stuck with modems with pretty old NAS, which they don't report
Ec/Io at all... :/

-- 
Aleksander


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