- Joined
- Sep 9, 2003

- Messages
- 1,078

- Location
- Chicago, IL

- Carrier(s)
- Verizon Wireless

- Device(s)
- iPhone 5s

From Wikipedia (if this is even correct):

Zero dBm equals one milliwatt. A 3 dB increase represents roughly doubling the power, which means that 3 dBm equals roughly 2 mW. For a 3 dB decrease, the power is reduced by about one half, making −3 dBm equal to about 0.5 milliwatt. To express an arbitrary power P as x dBm, or go in the other direction, the following equations may be used:

x = 10 \log_{10}(1000P)\, or x = 10 \log_{10}P + 30\,

and

P = 10^{(x/10)}/1000 \,

Case in point: if one phone shows -75dBm and another right next to it shows -72dBm, is that a significant difference? What's the threshold of "noticeable difference"?

Are there even acceptable ranges that the signal strength should fall within?

I'd like to compare two phones side by side here, so any info someone can share would be helpful. Thanks!