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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.
How about phones just print the dB signal loss and be done with it? A number should be far easier for someone to tell about signal strength than guessing by 0-5 bars.
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?
I'm quite sure that AT&T and Apple have always been aware that their phones were fudging the signal quality indicator on their product... Reality is hard to sell when your competitors fudge their numbers, too.
Holy hell the code for the Android OS StatusBarPolicy in the StatusBarPolicy.java file is a stinking mess. So much for Google having the best programmers in the world. A single public method -- installIcons() at the class level, and a pile of private methods doing all sorts of things. Hundreds of lines of different private variables and worst of all the slew of private anonymous classes.
This sort of mess make single responsibility principle weep.
that commented on /. about how Apple was making false claims about the incorrect signal bars? Surely if the responders on Friday had the balls to stand on a pedestal and make grand claims based on no evidence, they can have the balls to come back and admit they were wrong.
so what if the calculation is wrong or different between phones! It has nothing to do with the problem the iphone is having. If you normally have 4 bars with the wrong calculation, and you hold it and get no bars with the wrong calculation, then there is something wrong with the design of the phone, All apple is doing is trying to confuse the masses with technical facts hoping to confuse the issue and save money from all the lawsuits that are being filed.
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
You should perhaps rethink the temporal line on these events.
Why not use Frame Error Rate to indicate signal quality?
After all, Signal Strength tells you little if the Signal-To-Noise ratio is low. ... Alan
How about phones just print the dB signal loss and be done with it? A number should be far easier for someone to tell about signal strength than guessing by 0-5 bars.
Because 90% of the population has no fucking clue what decibels are? A logarithmic scale is a recipe for disaster in the consumer marketplace.
Actually, I think the unit in question is decibel milliwatts: http://en.wikipedia.org/wiki/DBm
Please help metamoderate.
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
I'll stick with Verizon where I have bars all over the state as opposed to AT&T where I didn't.
Voila! An actual, meaningful assessment of what the phone bars mean in real numbers from a calibrated instrument.
But but.. what would /. be without mindless speculation? Take your schmience elsewhere!
So... Why isn't the formula for calculating the bars standardised again?
Personally I'm wondering why part of it (on many phones) seems to involve dropping a couple of bars whenever I press the "call" button, without moving the phone. Presumably doing so invokes the "slightly less BS" mode. The other thing I'm wondering is why the more expensive the phone, the crappier the signal. I picked up a spare PAYG phone for about the same as what lunch cost me that day and it makes a very clear call everywhere. My old Ericsson K800i, not bad but not nearly as good. HTC Desire does better than the bars imply but still easily the worst of the 3.
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
Mod UP!!!
I am very sucseptible to "let's have another drink"
What do you mean a five-bar meter isn't a calibrated, precise, linear measure of signal strength? I know what the bars mean, I'm not stupid.
PANIC!!!
I am very sucseptible to "let's have another drink"
They compared the percentage, not the number of bars. From the article:
The iPhone 4 consistently displays a greater percentage signal strength than Android (as defined by the fraction of bars lit).
This space for rent.
I didn't think that sounded quite right, so I thought about it a bit. It turns out that your claim is partly true, iPhone OS will report a greater absolute number of "bars" about 1/2 the time, given a common baseline (both scales measure from the same zero, to the same peak "full" strength (which certainly isn't guaranteed).
Consider a scale from zero to twenty (chosen for the ability to represent this concept in ascii, as 5 x 4 = 20, conveniently giving us both multipliers 5 bars, and 4 bars, on the same scale, 0 to 20). Mapping between them shows that half the time they agree, the other half the time, iOS reports at most 1 more bar.
11111222223333344444 Google Android OS (four bar scale)
1111_222__33___4____ (numbers where they agree, _ where they differ)
11112222333344445555 Apple iOS (five bar scale)
Not surprisingly the scales agree most often where they start, and least often at the top of the scale. Of course, this comparison ignores the fact that each bar represents 20% of the scale on iOS, and 25% of the scale on Android. Your bars may (and do) vary.
If you mod me down, I shall become more powerful than you could possibly imagine.
Stick that in your hat, ya apple haters..
Still, how can a bug like that exist since day one and NO ONE noticed? Still smells like fish to me, and i like my iPhone.
---- Booth was a patriot ----
you're forgetting what kind of people you're talking to.
new sig
Remind me never to hire you.
If you mod me down, I shall become more powerful than you could possibly imagine.
I usually lose track of bars after I goes to 6 or 7 of them.
rewriting history since 2109
You fucking idiot..I asked you to test the the phone for bars...not test the phone in a bar...
dBm is an accepted abbreviation for a system where 0 dB = 1 mw. You can also write it dBmw but dBm is an accepted industry standard way of abbreviating it. bBm is a real common way of expressing transmission, and reception, power of radio waves. A powerful FM transmitter might be 80dBm, a GSM phone 33dBm max (though usually much less) and the signal received by said phone in the -100dBm to -80dBm range.
There's plenty of cases where you add a letter behind the dB and it is understood to mean a certain scale. dBC is understood to mean decibels of sound pressure level where 0dB = 20 micropascals but using a C-weighted response with respect to frequency. dBu means 0dB is equal to 0.755 volts RMS in to a 600 ohm load, and is used for pro audio levels often.
Scales that commonly use decibels as their function of measurement frequently have a 1 or 2 letter suffix to indicate you are use them. dBm is a real, real common one especially in radio, but in other electronics as well.
Ask any Blackberry for detailed info, it'll give you the signal strength it sees in dBm.
I do not suspect that any of the iPhone 4 users would be interested in letting me do this. We do own multiple spectrum analyzers at work, and there are enough Apple fanboys around that at least one of them is going to have an iPhone 4, but the chance that they let me tear it apart is about nil.
Just remember that the Android is open, so I can change the source code myself and get 11 bars! Show me another phone that gets that kind of signal strength!
- For the complete works of Shakespeare: cat
Why do they use bars at all? Why don't they use numbers? I suspect it has something to do with early phones and a little dedicated LCD space of bars was cheaper than a full numerical display, but we're well beyond that now.
No sig for you. YOU GET NO SIG!
Ours go up to eleven.
Have gnu, will travel.
I was actually summarising the articles I've read on this subject since the story broke. I didn't make the BP comparison, but several articles on the Internet did. Basically, both companies were arrogant in their initial response and slow to react. This seems to be typical behaviour of large corporates. And there was no "equating" of the scale of the problems; you're reading that into it. I merely reported what I had read.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
1. There is no problem!
2. You're holding it wrong!
3. The bars are wrong!
Based on what I see Apple has done two major mistakes with the phone; Creating an antennae setup that is VERY "error" prone (yes, more even than the competitors who use similar setups with their antennae). And "faking" a superior signal via extra bars displayed. The latter was obviously done to make their phone look that much cooler.
But you can't fault Apple for lying.. after all, all the fanboys are looking for is some excuse to hang on to prove everything is alright in their little world.
One reason exaggerating the signal reporting ain't cool is that the weaker the reception a phone gets the more it beefs up the transmission power. So for example some of us want to know whether or not if we keep our phone overnight by the bed it gets a significantly lower signal than if it's by the window so that we know where we ought to leave it when it's sleepy time but if this phone reports a full signal in either location (but the transceiver behaves differently) then not having that information may lead to unideal nocturnal positioning. You dig?
Wonder if AT&T had anything to do with that. Anyway, nice to know they kept their distance from my Nexus One, crapware and misleadingware alike.
Calling out bogus battery capacity claims.
Why not just get a stronger smart phone that goes to 5?
The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
I have never seen dBm/sqrt(Hz) before and I'm not sure what that wound mean. At work, we use dBm/Hz all the time, and I know that means: x_dBm = 10*log10(x_mW/Hz). Where x_mW is a measure of milliwatts from 1 Hz of bandwidth (BW). Power scales with BW, not the sqrt of BW, so I don't know where your unit could come from.
May be true but unlike the iPhone, you have a lot more than one or two phone options with the Android platform. The Droid doesn't have any issues. The Droid X doesn't seem to have this issue, but we won't know for sure until the 15th when it hits the masses. I don't hate the iPhone. I still use the G1 myself and have been happy with it. I like having a qwerty keyboard which the iPhones will never offer. The Moto Droid is one of the strongest overall phones to date, for me. Everyone has a difference or preference though, which is why the iPhone simply can't be for everyone. That and I wouldn't be caught dead running on the AT&T network.
...will introduce 'reception' as a feature.