1. new_to_BB's Avatar
    is -60dbm signal level good or bad, does it mean im getting strong wifi signal(on a computer I could see it in % values or a bar chart, here I can't)?
    how does it compare to -70dbm?
    04-01-10 08:45 PM
  2. jeffh's Avatar
    I don't know what's typical on wifi. On a CDMA cellphone, the strongest signal I have ever seen was -80 dBm. -60dBm is a 10x stronger signal than -70dBm and 100x stronger than -80dBm.
    04-01-10 09:22 PM
  3. new_to_BB's Avatar
    I read that higher signal level means weaker signal strength, so -80 is the strongest signal strength(weakest signal level) from what you've seen?


    I don't know what's typical on wifi. On a CDMA cellphone, the strongest signal I have ever seen was -80 dBm. -60dBm is a 10x stronger signal than -70dBm and 100x stronger than -80dBm.
    04-01-10 09:33 PM
  4. jeffh's Avatar
    -80dBm is the strongest signal I have ever seen on a CDMA BlackBerry. It corresponds to 5 bars. I have trouble holding a call at -105dBm to -110 dBm. That's 0-1 bar. But it's important to remember that the conversion of dBm to bars is not calibrated and can vary substantially between carriers and phones.

    dBm is a ratio of the (Received Power) / (Reference Power = 1mW). Log(base10) of 1 = 0, so 0 dBm would mean the received power was equal to the reference power.
    04-01-10 09:40 PM
  5. NetworkGuy's Avatar
    I am currently 5 ft from my access point and have a level of 47dbm. I would think 60dbm is a good to excellent connection?

    Posted from my CrackBerry at wapforums.crackberry.com
    04-01-10 09:44 PM
  6. jeffh's Avatar
    Your numbers are actually negatives, but yes, that's a very strong signal compared to cell phone signals. I'm on wifi as well, but don't have any way to measure the wifi signal strength.
    04-01-10 09:48 PM
  7. new_to_BB's Avatar
    so i am correct on the inverse relationship betwee signal strength and signal level?
    04-01-10 11:21 PM
  8. jeffh's Avatar
    I'm not sure what distinction you are making. Signal strength and signal level are just different words for the same parameter. Negative values for signal level and signal strength mean the received power is less than the reference power. For dBm measurements, the reference power is 1mW. 0 dBm means the received power is equal to the reference power. Positive dBm measurements mean the received power is greater than the reference power. There is nothing inverse about the relationship.

    Posted from my CrackBerry at wapforums.crackberry.com
    04-02-10 09:38 AM
  9. new_to_BB's Avatar
    04-02-10 08:26 PM
  10. jeffh's Avatar
    I read the thread you linked. I don't understand the poster's question. I have no idea what he means by better signal vs signal strength. Since he's talking about channels, he might be referring to wifi. If that's the case, is he talking about received signal or transmitted signal? I don't know. Given that I don't understand the question, I can't judge larrygump's answer.

    I suggest you look up the wikipedia article on decibel scales. I've explained it as best as I know how, but I can't easily type the math symbols in a post, and there's no point in it when I'd just be repeating what you can easily look up and read for yourself.

    Here are some links to other threads where this issue has been discussed.
    http://forums.crackberry.com/f61/opt...nection-34208/
    http://forums.crackberry.com/f52/sig...uations-35108/
    http://forums.crackberry.com/f52/sig...what-s-136045/
    04-02-10 08:52 PM
  11. new_to_BB's Avatar
    ya i think he was talking about wifi signal strength(received), and the topic was signal level(on BB) vs signal strength(received). i'll take a look at those links.

    But just a side note, I am getting - 75 dbm at my house 10 feet from my router, while at school i am getting -50-60dbm and the router is nowhere to be seen in the library, by intuition i'd say -75dbm is a weaker signal level(stronger received signal strength since my blackberry doesn't have to blast up the signal level)
    Last edited by new_to_BB; 04-02-10 at 09:57 PM.
    04-02-10 09:53 PM
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