Possible Duplicate:
Android: How to monitor WiFi signal strength
Is there a way to know the signal strength of a wifi network using code?
Naveen
Take a look at these:
getScanResults()
level
http://developer.android.com/reference/android/net/wifi/WifiManager.html
http://developer.android.com/reference/android/net/wifi/ScanResult.html
来源：https://stackoverflow.com/questions/5411626/android-wifis-signal-strength