Relation between Signal Level, Noise Level and RSSI

Pavel Roskin proski
Mon Jun 2 06:03:35 PDT 2008

On Mon, 2008-06-02 at 18:23 +0530, Raghavendra wrote:
> Hi,
> I have following two data, which display Signal Level = -79dBm, Noise Level 
> = -88dBm and RSSI of 177.
> Can any one tell me whats the relation between these three? any 
> equation..etc. basicaly I want to know how RSSI value is determined as 177?

It looks like RSSI is signed integer, so it's -79, the same as the
signal level.  177=256-79

There is no relation between noise and signal.

All details should probably be asked in the mailing list for your
driver, as they are hardware and driver specific.  If you want to know
more about physics or information theory, Google is your friend.

> Also if any one have idea about
> -90 ~ -80dbm: level 1
> -79dbm ~ -69dbm: level 2
> -69dbm ~ -59dbm: level 3
> -59dbm ~ 0: level4.
> what these level stands for?

That might be empirical levels used for displaying signal quality as
bars for the end users.

Pavel Roskin

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