-1

So my question is to ask if Signal Strength is accurate ?

this is how I calculated my DBM

 public void onSignalStrengthsChanged(SignalStrength signalStrengths) {

        super.onSignalStrengthsChanged(signalStrengths);
        int SignalStrength_ASU= signalStrengths.getGsmSignalStrength();

        signalStrength= (2 * SignalStrength_ASU) - 113; // -> dBm
}

this is an example of the data I went out today and collect in a dense park and to be honest is it possible to have a signal of 85? a positive signal?! BTW I am using note2

example of signal data

Moe Far
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UserBlanko
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  • Documentation says `Get the GSM Signal Strength, valid values are (0-31, 99) as defined in TS 27.007 8.5` a 99 value would give you the 85 you see there. I assume 99 have some significant meaning, probably specified in TS 27.007 8.5. Whatever that is – M4rtini Jun 20 '15 at 17:19
  • They mention this (here's PDF): http://www.etsi.org/deliver/etsi_ts/127000_127099/127007/08.05.00_60/ts_127007v080500p.pdf – Marcin Orlowski Jun 20 '15 at 17:22
  • how about is there another link that describe how many bars= -95 cause i know different provider have different calculation – UserBlanko Jul 03 '15 at 04:27

1 Answers1

1

The specification says this about signal strength values:

0 -113 dBm or less
1 -111 dBm
2...30 -109... -53 dBm
31 -51 dBm or greater
99 not known or not detectable

source (page 81)

The 99 value would givee you the calculated value of 85 that you see there. What to do when you get that value is up to you.

M4rtini
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  • thanks so when it is undetectable does it mean ghost? Or is there any reason it is undetectable? – UserBlanko Jun 20 '15 at 17:47
  • The specification does not say what could cause the signal strength to be ' not known or not detectable'. it is simply unknown. – M4rtini Jun 20 '15 at 17:50
  • okay just a side question i use my samsung S4 to collect the same data at the same position i had two different value of dBm so i concluded that different device have different dBm value? – UserBlanko Jun 20 '15 at 18:08
  • Different devices with different receivers\antennas, would probably show some variations in signal strength yes. – M4rtini Jun 20 '15 at 18:09