Slashdot Mirror
Android vs. iPhone 4 Signal Strength Bars Comparison
thisisauniqueid writes "In light of the clamor over the iPhone 4 Grip of Death, AnandTech recently reverse-engineered the phone's signal-strength-to-bars mapping. Because Android is open source, we can determine the corresponding mapping for Android in combination with the 3GPP spec referenced in the source, allowing the signal-strength-to-bars mapping for both Android and the iPhone 4 to be plotted on the same axes. This shows that the iPhone 4 consistently reports a higher percentage signal strength (as defined by the fraction of bars lit) than Android GSM devices at the same signal strength."
These measures aren't very useful without considering the noise floor...
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
The actual signal is amplified across most frequencies by an obscure side effect of the reality distortion field. If you were an Apple antenna engineer you'd know that.
All mobile phones have tradeoffs in antenna design in order to look pretty, because people don't like visible external aerials. Apple have come up with what should be a very good design but compromised it by not coating the metal in a dielectric layer. Apple have created bad publicity for themselves by coming up with a BP-like response to the complaints, but this won't affect their sales because Apple buyers don't take any notice of negative publicity for Apple products.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
my wife's iphone constantly reports 3-4 bars and 3g in places where my motorola milestone reports 1 or no signal. it's not until she goes to make a call that -- oops! no coverage.
His graph is erroneously labeled in dB, which is an arbitrary scale, whereas it ought to be labeled in dBm, which is received signal strength.
In case you're wondering,the B is a Bel, which is a factor of 10. A dB is a deciBel, which is 1/10 of a Bel. dBm is decibels relative to a milliwatt of signal strength.
The determined Real Programmer can write Fortran programs in any language.
...they independently confirmed a bug that Apple had already confirmed?
Probably 99% of the population has no idea that -80 dB is extremely good and -100 dB is awful. Further, the curve is logarithmic, which makes things confusing because most people are only particularly familiar with linear.
The article is worth reading. Right on the first page it explains what is really going on with the "grip of death".
In other news reports I have seen about iPhone 4, it was explained that the iPhone 4 has a strip of metal wrapped around the body of the phone that serves as the antenna. Not so! There are two strips, of different lengths, serving as two antennas. One antenna is for WiFi and GPS, and the other antenna is for cell phone service. The "grip of death" happens when you make an electrical contact between the two antennas (on the lower-left corner of the phone).
According to the article, bridging the two antennas with your hand causes a drop in cell phone signal to noise ratio of about 24 dB. This can be enough to cause a dropped phone call, if you are already in an area with weak cell signal strength. If you are in an area with good cell strength, you won't drop the call and you might not even see the signal strength bars change.
And according to the article, as long as you don't bridge the two antennas, this phone really does do a better job of locking on to a weak cell phone signal.
So, if you have an iPhone 4, definitely invest in some sort of case that insulates the two antennas. And the article scolds Apple for not having put some sort of insulation over the antennas; presumably a future iPhone will do so.
Other pages of the article discuss other things. I did like the page where Anand explains why Apple's claims are valid that the screen is sharper than the human eye can resolve.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
Of course. Because the average phone user knows what a dB is and would much rather see it than a bar graph. My mother was just telling me the other day that she gets a -10dB attenuation in the kitchen compared to the lounge.
They don't know that right now.
Switch every phone over to display dB directly and everyone in the world would understand it in 6 months, though some would bitch about it for years to come.
People don't need to know what the numbers MEAN, they need to know that at 100 it doesn't work, and at 96 just barely works, but 80 is golden, and they'll figure that out fairly quickly.
Of course in reality all people really want is the phone to give them a good reason why they lost their call, can't get calls or have shitty data rates, and that could more accurately be represented with a simple block of text when the users asks and a green or red light in place of the bars.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
Seriously?
You're comparing the iPhone using some physical technique to infer the signal level to bar mapping, taking into account all the variables of the phone hardware ...
And on Android you're just looking at the source ... not even the phone itself ...
And this is supposed to be some sort of comparison? Whats next? Submarine A goes 25 knots submerged, Space Shuttle X launches into space at 36k knots. Which one will get you to BurgerKing first?
When you compare things using completely unrelated ways of gathering your input data you find that your results are ALWAYS wrong, even if you can't see it or they agree/disagree with what you thought.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
After I got my iPhone 3G the very next software update included a change to the "bar algorithm" that was marketed as "improving user understanding of the signal meter" or somesuch. It was in response to user complaints of low signal strength, and somehow (miraculously) the reception improved... more bars.
So they're rolling back this change?
MJC
IANARFEE, but I am a EE who works with RF.
For all of the millions of dollars being lost on productivity aimlessly discussing 'bars'..
Can someone please dissect the antenna and then connect it to a calibrated spectrum analyser? This is so mindbogglingly trivial to do it is beginning to hurt my soul. I do similar exercises at work with new, untested antenna designs. I am sure I am not the only one.
For comparison, do the same to other phones and publish actual measurements of received signal drops and the effect from the disturbance caused from closing your hand around the antenna. This is similar to how touching an old rabbit-ears style antenna effects the picture on a analog TV broadcast, if the effect is as I suspect.
Voila! An actual, meaningful assessment of what the phone bars mean in real numbers from a calibrated instrument.
An uncalibrated receiver, such as the iphone, is not a proper tool to do this.
*grumble* *off my lawn* *grumble*
..don't panic
that's okay, my Spinal Tap smart phone goes to 11 bars !!
who prays for Satan? Who in 18 centuries has had the humanity to pray for the 1 sinner that needed it most? ~Mark Twain
An alternative could be to have it show a percentage between 0 and 100. As this might be too distracting perhaps just show them in groups of 20% each. To save space, you could leave out the number and just show a block.
That way you can easily show the strenght of the reception and made it understandable for everybody.
Don't fight for your country, if your country does not fight for you.
You fucking idiot..I asked you to test the the phone for bars...not test the phone in a bar...
Why not leave user interface design to people who know that there are a lot of colorblind people out there?