Please can we have Signal Strength Explained - Hero, G2 Touch General

I have always wondered what ment what and what was good and what was bad and what was the best.
I have my idea's that -100 is bad and -25 is good. but i just wanted to be sure...
My signal is -89 dBm and the moment
and i dont know what 12 asu means.....
Please can someone drag me out of stupidity for a few hours..
Marc

Okay, not 100 percent sure Bout this but ill use some of my physics and maths knowledge with a bit if Wikipedia help to try and explain. Dbm is shorthand for dbmw..ie decebel milli watts. It's a measure of the amout of power your phone is using to retain that signal. Since its decibels then its a logrithmic measurement,you can't get zero signal.
Baisically...-100dbm is like 0.00000000000033 watts
-25 dBM is around 0.0000003 watts.
It's just a way of measuring really small amounts of power.
Not too sure about the other thing tho. Hope this helps

In laymans terms, we use dB simply to make power levels more usable/manageable. You'll see that immya's response includes all kinds of crazy numbers which would not be fun to write every time. However dB don't really have any units. That is, if one signal is twice as strong as another then it is 3dB stronger. If I have ten times as many boxes of cheerios as you, then I have 10dB more than you. dB is always used as a ratio like that.
If you don't want to use it as a ratio comparing two things, then you need to know the unit. So, I can't say that my signal strength is 20db - it makes no sense. What is that measured in? Boxes of cheerios? We need to know if that signal strength is measure in milliWatts or Watts or whatever. Therefore, you just tag on either a m or W (usually) for signals strength. If you were to see a signal strength of +3dBm that would mean it is twice as strong as 1milliwatt (which of course is 2 milliwats). If you see +3dBW then it would be 2 Watts. Like wise if you see -3dBm that means it is half as strong as 1milliwatt or just 0.5milliwatts.
If you are following along then you can clearly figure out that 0dBm is the same thing as saying 1 milliwatt and 0dBW is the same thing as saying 1 watt.
Obviously, the actual received signal strength displayed on your phone is usually something like -90dBm which means it is really really week compared to 1 milliwatt........which is normal of course. And -80dBm is 10dB (no unit) stronger than -90dBm.
hope that helps

@clobber: it does indeed, thanks very much - I didn't know about the m & W notation previously

that is great - thank you.....

Related

Better signal strength ?

Is there anyway to improve the signal strength on the mini S ? It doesnt seem to be giving me anywhere near as strong a signal on O2 as I got with my Nokia 3650.
Im sure I remember reading something on a model of phone where you could improve the reception although it hit the battery a little.
your thinking of the nokia's and other phones where you could enter a keypress and it would increase the signal and reduce battery life or you could decrease signal and increase battery life. but with my jam in Texas i do have a really bad reception issue, but thats because i have the international jam thats 900/1800/1900 and cingular runs on 850/1900 so thats why i'm getting the k-jam which is quad band... maybe if you go to the power settings and click move the slider to best performance, see if that helps
How do you realize signal strength is lower? Have you actually noticed lower speech quality or is it only the lower count of antenna bars on your display?
Keep in mind that there is no standard on how signal strength has to be displayed. Nokia phones tend to show more bars, whereas a Siemens phone receiving the same signal strength (in dB) would show fewer bars. They do that intentionally, so customers think a Nokia has better radio quality.
inquisitor said:
How do you realize signal strength is lower? Have you actually noticed lower speech quality or is it only the lower count of antenna bars on your display?
Keep in mind that there is no standard on how signal strength has to be displayed. Nokia phones tend to show more bars, whereas a Siemens phone receiving the same signal strength (in dB) would show fewer bars. They do that intentionally, so customers think a Nokia has better radio quality.
Click to expand...
Click to collapse
My wife said I was going louder and quieter on one occasion although I could hear her fine. In some places its only on 1 bar on the signal strength indicator. I believe there are 3 or 4 in total arnt there ? So I would consider it a weak signal.

A cross-country trip, the Froyo Radio and what it might mean to you!

So I just recently took a trip from northern California to Tennessee and had some interesting results with the Froyo radio. For reference I own the ATT-version Nexus One and have data roaming enabled.
When I used the phone before Froyo radio I had many problems with the 3G switching to Edge and back when needed which caused random data dropouts. Even turning the phone off and back wouldn't force the phone to switch connections to Edge when needed which would make me very frustrated in times of need.
On my trip I found something very interesting, not only did 3G and Edge switch almost perfectly, but Edge performed MUCH faster than before. While it isn't as important now in a world of 3G coverage, when I was on the "edge" of civilization I still got surfing speeds that were not far behind that of 3G speeds. My browsing, and most importantly Google Maps usage rarely suffered a performance hit despite where I was or what type of connection was available to my phone.
There was a difference between performance; 3G would act like Comcast and Edge would be a little behind, but in terms of actually surfing the Internet the extra 2-5 seconds it took to load up a desktop webpage didn't make a difference.
Technically the bandwidth speeds were much different. 3G performed from 1 to a max of 2 megabits down and .3-1 megabits up, while Edge showed speeds of 300-500 kbps down and 100-200 up.
One thing I did notice throughout the trip is the Nexus One's signal meter did not report correctly, there were times where it showed no signal and I had super fast connection, and also times when it would show full or near-full bars and there was no connection.
Hope someone finds this info useful!!! I'm very happy with the coverage my Nexus One gets with the Froyo radio now!
I have always found that my nexus holds calls and has fast data showing zero bars. One reason I've always loved the nexus
Just a point of clarification, EDGE has a maximum theoretical bandwidth of 473.6 kbits/s for 8 timeslots.
In real world conditions EDGE should have throughput of 236.8kbit/s with 4 timeslots(which is what most carriers employ).
Dan
Wonder if there's and app/mod to replace the signal bar with the actual signal #s?
Hey Sellitus, what else did you find working/not working on that trip?
I am considering a longer drive (SF to NY) and want to know about battery life, apps that were really handy, and which weren't.
SiNJiN76 said:
Wonder if there's and app/mod to replace the signal bar with the actual signal #s?
Click to expand...
Click to collapse
hey that would be nice. just like how cyanogen puts the battery percentage, it would be nice to have the dBm level of signal overtop of the signal meter.
RogerPodacter said:
hey that would be nice. just like how cyanogen puts the battery percentage, it would be nice to have the dBm level of signal overtop of the signal meter.
Click to expand...
Click to collapse
The dBm and signal bar IMO opinion are rather pointless in regards to data. Having a very poor 3G signal will always be faster than a full GPRS signal.
Also, a signal meter in terms of DB would jump around quite a bit...
sprinkles said:
Hey Sellitus, what else did you find working/not working on that trip?
I am considering a longer drive (SF to NY) and want to know about battery life, apps that were really handy, and which weren't.
Click to expand...
Click to collapse
Well for ATT I hit data roaming quite a few times, and although it worked on edge pretty quickly during those times it would randomly drop when the R was showing randomly. I think what happened a lot on the trip is when I was out in the middle of nowhere bouncing between towers would cause random dropouts, but they were usually no more than a few seconds.
I don't remember which apps specifically though a few also did not like the trip, but most would hang and resume in a few seconds after data was reconnected even if the signal strength showed it was connected the entire time with signal. Sometimes Google Maps hung, though it was rare and I noticed it more because I used it near constantly on the trip.
If I were to give advice to anyone looking at a cross country trip, buy a map or get offline GPS maps to help. We bought a map and it proved valuable at times, though we rarely needed it.
I wonder if the "enable data while roaming" setting had anything to do with that. Maybe an internal bug.
torchedlh said:
Also, a signal meter in terms of DB would jump around quite a bit...
Click to expand...
Click to collapse
I don't know how a number jumping around would be any different than a graphical signal meter jumping around. The iPhone has had this hack for a long time where you can replace the signal meter with the dBm reading. Though I've never owned the iPhone, but seen it on friend's iPhone before.
I know I'm often going into the android settings to look at my dBm reading, didn't jump around too much for me to see.
I've been having some reception issue lately with AT&T around my hometown (usually its quite good),so I did some googling, and found plenty of info on radio signal, and how to interpret -dBm, but I'm still baffled by the ASU. I really couldn't find much, just some random post on a random forum that left me with some questions:
In a 3G network your cell phone tries to open three channels to three radios so they can locate you and hand you off properly.
Those three channels make up you ACTIVE SET.
ASU is ACTIVE SET UPDATES or the rate at which your phone is able to update its location to the towers/radios.
This rate is affected by signal strength, load, and probably a lot of other factors that I haven't puzzled out yet.
Click to expand...
Click to collapse
Can anyone shed some more light on this? Usually at home I have 2 bars of HSDPA, somehwere in the -90s dBm, and anywhere from 4-8 asu.

signal strength vibrant vs. g1

the more i look around the more i wonder if its hardware not software....
s/n ratio on this thing sux. sitting on my front porch line of sight to the closest tower is .5 miles. with the vibrant im getting 0-1 bar 3g with speeds 0f 512kbp on average. my g1 getting next to it shows full bars, and averages 4.5mbp have seen almost 7mbp in the same spot with the g1. the vibrant picks up 7-9 satellites with aan average s/n of 15-18 db, and might lock on to 1 or 2 after about 10 min. the g1 in the same location hits 12 satellites with a minimum of 35db and locks on to 5+ within seconds on wifi, the vibrant shuld have a clear advantage being able to use wireless-n, but on the front porch im seeing about a 30-35db signal, the g1 in the same spot, but on wireless-g see's 50+ db, the g1 stays connected all the way to my mail box, the vib drops less than 1/4 of the way there. so, hopefully a software update cures this, otherwise it sounds like its hardware related.... ( im pretty sure that i didnt buy an i phone)
after 5 days of checking, im averaging 60-75% of the time with out service according to the phone.
any one else care to share actual figures comparing to another device in same location, not just how many bars etc...
i purposely did all my measurements outdoors/close to a tower within line of sight to ensure a good solid stable measurement. my porch is within 20 feet of my router , line of sight thru an open door for the wifi tests.
None of these numbers make any sense, furthermore is the G1 on the same CID as the Vibrant? Have you done tethering and not a speedtest on the phone?
heygrl said:
None of these numbers make any sense, furthermore is the G1 on the same CID as the Vibrant? Have you done tethering and not a speedtest on the phone?
Click to expand...
Click to collapse
lol.... they dont make sense? they are actual signal level readings @ a hardware level. that wey we arnt trying to compare any of the falce readings that the software covers up..... like gee, why does my batt icon still show almost full when in actuality it is at 25% remaining.
and yes, i have teathered to it. it still does not change the fact that compareing actual signal strengths of a brand new top of the line device are crushed by a antique first gen device.
i have spoken with samsung, i recomend any one woth poor radio performance to contact them and start a help ticket. at 1-877-EZ2GALAXY (1-877-392-4252)
t1h5ta3 said:
lol.... they dont make sense? they are actual signal level readings @ a hardware level. that wey we arnt trying to compare any of the falce readings that the software covers up..... like gee, why does my batt icon still show almost full when in actuality it is at 25% remaining.
and yes, i have teathered to it. it still does not change the fact that compareing actual signal strengths of a brand new top of the line device are crushed by a antique first gen device.
i have spoken with samsung, i recomend any one woth poor radio performance to contact them and start a help ticket. at 1-877-EZ2GALAXY (1-877-392-4252)
Click to expand...
Click to collapse
I've never seen signal strength of 55db on WiFi. Same for the rest of them, they don't make sense.
Run your speedtests while tethered and not on the phones themselves.
Use Service Mode for RSSI readings on the Vibrant
The battery meter doesn't show full with 25% remaining
my bad, i was trying to do it all from memory not looking @ my notes.... signal on the g1 was -30dbm the vib was -55dbm on the porch
gps signal strength ( *#*#1472365#*#* gps test) data was in dBHz
just did it again, got my best TTFF/TTF of 148 seconds and im seeing my best ever accuracy bouncing between 15-20 meters
sad that these readings are the best performance ive seen...
i have this growing suspicion that there was a reason samsung installed an optional GPS antenna socket on the phone (next to the sim card, by the beveled corner)
are there other phones out there with a socket for an optional gps antenna?

Signal Strength Booster?

I get poor reception on my Incredible whereas my parents get great reception on their phone. A little googling and this popped up:
http://www.onlyincredible.com/incredible-booster.html
is this legit at all? i'm not a technical guy so I have no idea.
I call bull****. They used to sell these things for regular cellphones. They didn't work then, either.
slorange said:
I call bull****. They used to sell these things for regular cellphones. They didn't work then, either.
Click to expand...
Click to collapse
I was thinking the same thing but trying to be hopeful ya know? I really need some signal boost. I average around -90 dBm
If you're desperate, it's not like $2 is a huge sacrifice for a likely useless piece of plastic. I don't know I usually get between 80-100dBm at my house and i have no complaints about the service... The bars don't necessarily tell the whole story. 85dBm is 5 bars on my 6bar signal meter, so keep in mind that bars don't necessarily tell how mcuh signal you have. With the stock 4 bar meter, I would never have 4 bars at my house; usually 1 or 2; sometimes 3.
Jes7er said:
If you're desperate, it's not like $2 is a huge sacrifice for a likely useless piece of plastic. I don't know I usually get between 80-100dBm at my house and i have no complaints about the service... The bars don't necessarily tell the whole story. 85dBm is 5 bars on my 6bar signal meter, so keep in mind that bars don't necessarily tell how mcuh signal you have. With the stock 4 bar meter, I would never have 4 bars at my house; usually 1 or 2; sometimes 3.
Click to expand...
Click to collapse
I go by the dBm and just sitting my room I can go from -85 up to -120
I always thought that it would be normal for my dBm to be in the -60 range. Am I wrong or is -80 to -90 okay?
I get -91 to -106 in my room and I have good enough signal to do anything I want. Also my friend bought one of those for his Eris and thinks it actually hurt his reception but I can't imagine there's a difference with or without it
morph3k said:
I go by the dBm and just sitting my room I can go from -85 up to -120
I always thought that it would be normal for my dBm to be in the -60 range. Am I wrong or is -80 to -90 okay?
Click to expand...
Click to collapse
Sent from my Incredible using XDA App
If you want something to boost your signal this is one of the only things I've found that will actually do it..... http://www.tigerdirect.com/applicat...CODE=GOOGLEBASE&cm_mmc_o=VRqCjC7BBTkwCjCECjCE
They are normally priced at $120 but can be had for $15. I bought one and currently use it in both my vehicle and home. It will boost the signal for me from around -105 dbm in my house to around -90 dbm, but I've seen it get as good as -81 dbm. I plan on buying another that way I don't have to keep moving it around.
They say it works within a 6 ft radius of the plug but I've found that you need to be a little closer than that to it.
-80dbm is the best signal possible. Also, cdma signal fluctuates. Don't expect it to stay at a consistent number. Unless you're having issues with dropped calls or slow data, I wouldn't spend another second concerning yourself over it.
Thanks for this... now would two of these work better then one?
androidtrkdr said:
If you want something to boost your signal this is one of the only things I've found that will actually do it..... http://www.tigerdirect.com/applicat...CODE=GOOGLEBASE&cm_mmc_o=VRqCjC7BBTkwCjCECjCE
They are normally priced at $120 but can be had for $15. I bought one and currently use it in both my vehicle and home. It will boost the signal for me from around -105 dbm in my house to around -90 dbm, but I've seen it get as good as -81 dbm. I plan on buying another that way I don't have to keep moving it around.
They say it works within a 6 ft radius of the plug but I've found that you need to be a little closer than that to it.
Click to expand...
Click to collapse
Sent from my Incredible using XDA App
patches152 said:
-80dbm is the best signal possible.
Click to expand...
Click to collapse
How do you figure this?
I've seen my signal get better than -80 dbm.
patches152 said:
-80dbm is the best signal possible. Also, cdma signal fluctuates. Don't expect it to stay at a consistent number. Unless you're having issues with dropped calls or slow data, I wouldn't spend another second concerning yourself over it.
Click to expand...
Click to collapse
I know people here don't take bars for much, but why is -80 only 2/5 bars if it is all i can expect? I've only had a couple dropped calls so you are probably right that i shouldn't worry about it.
androidtrkdr said:
How do you figure this?
I've seen my signal get better than -80 dbm.
Click to expand...
Click to collapse
I've never seen mine better than -78 unless it was some weird fluctuation for a second
0 would actually be the best possible. But it can never happen, so, meh.
As far as highest signal strength possible, I've been in the -30's before. That's the highest I've ever seen.
Same, -32 was my best
dpwhitty11 said:
0 would actually be the best possible. But it can never happen, so, meh.
As far as highest signal strength possible, I've been in the -30's before. That's the highest I've ever seen.
Click to expand...
Click to collapse
Sent from my ADR6300 using XDA App
Your head absorbs wireless signals.
So, use the speakerphone more often, or better yet, use a good quality Bluetooth ear piece so the phone can sit near a window still.
morph3k said:
I know people here don't take bars for much, but why is -80 only 2/5 bars if it is all i can expect? I've only had a couple dropped calls so you are probably right that i shouldn't worry about it.
I've never seen mine better than -78 unless it was some weird fluctuation for a second
Click to expand...
Click to collapse
keep in mind that CDMA phones with VZW use two radio frequencies. one is voice, the other is data. so the "bars" and 3G doesn't do much to specify which of those two network connections its representing. my guess is that it's representing data strength, not voice.
-80dbm is the "best" signal strength i've ever seen a verizon wireless cell phone have. and that's based on other phones, such as blackberries, winmo, etc...i'm not sure if it gets any lower than that on CDMA networks. i know my WI-FI, when at the strongest, is usually -40 or -60 dbm.
for example, sitting at home my signal is -84 dBm, and that is pretty much full strength
also, the value we are discussing is how "loud" the signal is. take into consideration that network traffic will also impact service in varying ways.

[BUG] Signal Strenght Indicator

so here i got 3 Android phones
all sitting on the same spot
2 of them (SGS / XT720) shows 3 or 4 bars signal strength, but SNS only shows 1 bar, 2 at best.
however a quick test using 3G speedtest confirms the same download/upload speed as the 2 other phones.
and there's no problem calling even when it only shows 1 bar.
Can any body confirm this?
Go to settings > about phone > status and post the signal strength of each of them (should be in dBa). If they're the same, then ya either the SGS phones are overinflating their strength or the Nexus is reporting lower than it should.
AllGamer said:
so here i got 3 Android phones
all sitting on the same spot
2 of them (SGS / XT720) shows 3 or 4 bars signal strength, but SNS only shows 1 bar, 2 at best.
however a quick test using 3G speedtest confirms the same download/upload speed as the 2 other phones.
and there's no problem calling even when it only shows 1 bar.
Can any body confirm this?
Click to expand...
Click to collapse
your prolly just holding it wrong
*sarcasm*
slowz3r said:
your prolly just holding it wrong
*sarcasm*
Click to expand...
Click to collapse
I c wut u did thur!
Touche, good sir, touche.
SGS -97 dBm 8 asu
SNS -107 dBm 5 asu
XT720 -84 dBm 7 asu
does that mean anything to you guys?
AllGamer said:
SGS -97 dBm 8 asu
SNS -107 dBm 5 asu
XT720 -84 dBm 7 asu
does that mean anything to you guys?
Click to expand...
Click to collapse
seems like it is displaying signal strength wrong, I believe it is the farther from 0 the better the signal
im at -75 and full bars 3G
anyways... that's what i'm saying the actual usage is good, and 3G speed is good
but the bar indicator is always like in 1 bar or 2 bar... which is kinda wrong
AllGamer said:
anyways... that's what i'm saying the actual usage is good, and 3G speed is good
but the bar indicator is always like in 1 bar or 2 bar... which is kinda wrong
Click to expand...
Click to collapse
try restarting your phone? so it re-associates itself with the network
that would have been the first thing i do when i try to nail a bug
that's why i wanted to hear the experiences from the rest of you
just trying to find out if this is a bug specific to my phone, or if it's something that is affecting everyone
-97db with three bars displayed here.
Sent from my Nexus S using XDA App
The farther it is from 0 in the negative, the worse the strength is. The best strength I've ever seen on an android phone was -69. Worst is in the -100's so it looks like the Nexus is actually getting worse signal, not just reporting worse...maybe an antenna problem =(
dinan said:
The farther it is from 0 in the negative, the worse the strength is. The best strength I've ever seen on an android phone was -69. Worst is in the -100's so it looks like the Nexus is actually getting worse signal, not just reporting worse...maybe an antenna problem =(
Click to expand...
Click to collapse
quite the opposite, 0 is just a reference point, the farther from zero the better
Mine is -101 with 2 bars.
I'm not sure where you're getting this from, but you're saying -100dbm is better signal reception than -70dbm? If that's the case then the signal strength reporting is completely reversed... as I have full bars in my apartment and it shows -72dbm, and at work I have 1 to 0 bars and it says -101dbm. It's been like this for all of my phones.
Also speed tests at home give me 500k/s down and 50k/s up while at work I only get 60k/s down and 20k/s up...
slowz3r said:
quite the opposite, 0 is just a reference point, the farther from zero the better
Click to expand...
Click to collapse
AllGamer said:
SGS -97 dBm 8 asu
SNS -107 dBm 5 asu
XT720 -84 dBm 7 asu
does that mean anything to you guys?
Click to expand...
Click to collapse
It seems like the SNS is getting far worse ACTUAL reception than the other two phone.
-107 is very bad comparing to -97 and -84.
Are all 3 phones on the same carrier?
clubtech said:
It seems like the SNS is getting far worse ACTUAL reception than the other two phone.
-107 is very bad comparing to -97 and -84.
Are all 3 phones on the same carrier?
Click to expand...
Click to collapse
XT720 and SNS both are on Wind 1700/2100
SGS is on Fido 850/1900
AllGamer said:
XT720 and SNS both are on Wind 1700/2100
SGS is on Fido 850/1900
Click to expand...
Click to collapse
That's interesting as there is a huge difference between the SNS and the XT720.
-84dbm means very good reception and -107 is at the end of the workable spectrum (at -113 you basically can not place calls).
I am also noticing very bad reception on my SNS but i thought that it is due to T-Mobile's crappy network. i have no other T-mobile device to compare it with though so i start to wonder if its the Nexus S that has crappy reception or T-mobile.
Try to do more tests in other locations with the XT720 and the SNS and see if you always see such a huge difference when both devices are in exactly the same spot.
I am interested in your findings.
And as for your initial question, there is no bug in the signal indicator as -107db is very bad signal so the indicator is correct.
Okay please allow me to clear up some misunderstanding in this thread...
First of all, dBm is a logarithmic measure of signal strength with respect to 1mW. So, a smaller (i.e. more negative) reading means that you have lower signal strength.
Just to give an example: -50dBm is a much better signal than -100dBm.
Alright, so now let's move on to the next issue: You can't compare signal strength on two phones which are running on different networks. Why? It's possible that you have a strong signal from Fido and a weak signal from Wind, or vice-versa. If you want to compare the RF capabilities of two phones, you should make sure that they are connected to the same network and even the same cell (you can check the service menu to make sure that they are on the same cell).
And finally: The Settings>About Phone>Status is usually not a very accurate measure of signal strength, since they are rounded off to some pre-determined list of values (So for example, if it is jumping between -100 and -110, it might actually be jumping between -104 and -105). You should instead go to the phone's service menu (i.e. you type in some code into the keypad) where you will get an exact measurement.
My friend happened to have the XT720 while I have SNS, and we happened to be at a same location where my SNS can't maintain the connection (only able to connect at one room spot with 0 bars and unable to hear a thing due to choppy voice when I tried to check voicemail) and XT720 still got 2~3 bars anywhere in the room and able to make phone calls. We are both from same carrier. We left our phone on table side by side without touching it. So despite the bars on phone nor the signal number in setting menu, real life experience tells me XT720 does have better reception than SNS sadly D: I was embarassed that night when other friends laughted at my supposely better phone

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