wireless signal strength

[Christian Verdani]

Hello,

i want to query the signal strength of the nearby accesspoints on my
notebook.
I found out that i have to query the NDIS drivers, however the MSDN does not
offer smaple code how to do that (or i am to silly to find one).
I am working with visual c++. Can anyone tell me how to do that or can
anyone tell me a better solution?


sincerly,
Cristian

 

[Maxim S. Shatskih]

Try WMI, this is possibly the easiest way.

You can also try to send OID_802_11_RSSI to the kernel-mode components via
IOCTL_NDIS_QUERY_GLOBAL_STATS.

 

[Christian Verdani]

thanx,

can you tell me where i can find more detailed information?

 

[Michael Grobelkovsky]

See DDK for OID_802_11_RSSI.

Download also Oidscope.exe aplication.
It simulates OID_802_11_RSSI.

Michael.

 

[Christian Verdani]

Hello,
i have fought throught the MSDN and a few web pages. now i have a solution,
hoever, i don't know how to extract the data from the result.

The code snipet looks like this:


hres = pSvc->ExecQuery(
bstr_t("WQL"), bstr_t("SELECT * FROM
MSNdis_80211_ReceivedSignalStrength Where active=true"),
WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY, NULL,
&pEnumerator);


IWbemClassObject *pclsObj;
ULONG uReturn = 0;

while (pEnumerator)
{
HRESULT hr = pEnumerator->Next(WBEM_INFINITE, 1, &pclsObj,
&uReturn); //WBEM_INFINITE

if(0 == uReturn)
{
cout << "Need to BREAK!" << endl;
break;
}

VARIANT vtProp;
VariantInit(&vtProp);

// Get the value of the Name property
hr = pclsObj->Get(L"Name", 0, &vtProp, 0, 0);
// wcout << " OS Name : " << vtProp.bstrVal << endl;

VariantClear(&vtProp);
}





is there any location that describes the results i get from my query?





sincerly,
christian

 

[Arkady Frenkel]

Look at http://www.pcausa.com/Utilities/macaddr2.htm
Arkady

 

[Pavel A.]

No, MSNdis_80211_ReceivedSignalStrength is the RSSI value of the
currently associated AP.
You need to get the scan list (SSIDs with their RSSI).
If you prefer using WMI, please search in the WMI newsgroups
( microsoft.public.windowsxp.wmi ...)

Or follow the advise of MVP Arkady Frenkel.

To interpret results of all these queries, you need description of
the 802_11 specific OIDs in the latest DDK documentation.
(if you haven't read it yet, do this now).

--PA

 

[Arkady Frenkel]

Maybe Cristian mean how to treat received value , in this case miniport have
to return it in
decibel milliwatts ( dBm ) and typical range are from -10 to -200
Arkady