Mobile Phone Signal strength ….. What does it mean?

I’ve been having generally poor reception recently on my Sony Xperia Z3 (on EE).

I’ve checked the signal strength shown on the phone …. It’s saying -106 dBm. 34 asu

What does this actually mean?? What is a good strength ??

Well, -87dB on my iPhone equals four ‘bars’, and I’ve just gone outside, and got -68dB, and five ‘bars’, so from that I think it’s telling you that your signal strength is really poor!
Higher the number, poorer the signal.
In iOS, there’s the facility to tap on the signal strength and switch it between dB and graphic ‘bars, not sure if that’s available on your OS.

There’s no standard for representing signal on phones. Varies per manufacturer and even between products, and then what they choose to represent. Signal strength, signal quality, some combination of the two, some random meaningless value.

You can actually still get a good quality voice connection with low signal strength, and vice versa, and then data quality can vary regardless of the two plus depending on the data connection (GSM, Edge, 3G, 4G, etc), which may vary. You could get 4G data connection with low signal. Then again a Quality of Service may apply in the network and throttle it down despite a good data connection.

As for the values you’re seeing, it’s a measure of signal strength or power in decibels. -106 dBm could indicate a low strength signal, but no indication of quality.

And then is it indicating just received strength or transmit as well. Transmit power varies on need. Low strength received may result in high transmit strength, and vice versa. Either may compensate for the other. Although high transmit power will drain the battery more.

Same phone, same issue.
Granted strength may not equal quality, but to me it’s a bit disconcerted that it now shows little/no signal at my desk and at home when the last phone (same network) had a good strong signal. Turning preference from 4 to 3g sees ‘bars’ increase, but that seems a step backwards in an area well covered by 4g.

For me 4G seems to work much better with fewer bars than with 3G. In other words it’s quite usable with one or even zero bars, whereas 3G never was

Hhhmmmm. Yes ,….. I never thought about changing to 3G or even 2G but when I did I get full bars ……

However I’ve just spent 90 mins in a car journey with someone and just about the whole journey. I saw signal 2 bars less or so Both on EE on 4G . But despite showing no signal I could make a call

Strange

In iOS, there’s the facility to tap on the signal strength and switch it between dB and graphic ‘bars

Not by default there isn’t. I suspect you are either using a jailbroken iOS addition or you have activated Field Test Mode at some point.

Not by default there isn’t. I suspect you are either using a jailbroken iOS addition or you have activated Field Test Mode at some point.

Never needed to fanny around jailbreaking my phone, can’t see the point, and as to the second, I only have a vague idea what you’re talking about.
[edit]Oh, right, that’s what it’s called, is it?, I remember reading something ages ago, but I’ve just had to google it to find out:
Tapping in *3001#12345#* then pressing call puts the phone into Field Test Mode, which I didn’t actually recall it being called when I did it, I left it in that mode, because I like to have the choice.

Hmm I thought it might be a jailbreak because the other day you described tapping on the time to get a list of tabs which is also functionality I don’t see.

Field Test Mode involves this:

How To Check The Actual Signal Strength On Your iPhone

The time thing is like this, scrolling down the page gives you the page header looking like so:

Scrolling the other way, or tapping on the time gives you this:

Showing the list of open tabs across the top of the page, once that shows, tapping the time again automatically takes you straight back up to the top of the page.
Simple, really.
Or it seems simple to me, it’s just built-in iOS functionality as far as I know, or at least on the pad; the phone is obviously different.

Usually its an RSSI a Received Signal Strength Indicator that you see on your phone.

What does that mean? It’s the Cell site signalling back to the phone how well it can hear YOU. After all a mains powered tower 20m in the air with multiple antenna is going to be belting out a signal that can be heard by the right kit for one of a hell of a distance. Compared to a battery powered device with no external antenna and a case designed for form over RF coverage, stuck in your arse pocket.. Which do you think is going to be the more efficient transmitting and receiving device.

Ps.. Disclaimer I work for a mobile phone company.. not in mobile but in LAN/WAN/WiFi so have done the 3G/4G training just out of academic interest and also been a radio amateur for over 30 years dabbling in the VHF/UHF digital side of things.

t least on the pad; the phone is obviously different.

Ah right, yeah I get tabs on the iPad, I thought you were describing phone functionality on that thread that I didn’t get. (My iPhone is ancient, 4S, so despite being on latest iOS 9 available for it, not everything is supported)

It’s saying -106 dBm

That’s very low!

The 3G signal level is identified by a measure called RSSI (Received Signal Strength Indication) and is measured in dBm. RSSI is a measure of the available signal plus the noise in band. A level of -50dBm is a perfect signal and at -110dBm (usually earlier) you’ll lose the 3G connection.

• -50dBm to -75 dBm – High Signal (good voice and data)
• -76dBm to -90 dBm – Medium Signal (good voice and data)
• -91dBm to -100 dBm – Poor Signal (good voice data, marginal data with drop-outs)
• -101dBm to -109 dBm – Very poor Signal ( voice may be OK, no data)
• -110dBm to -113 dBm – No signal

http://forums.whirlpool.net.au/archive/2473085

Your comment about having low signal strength and still being able to make voice call –

What may be happening is that you are on a 4G doing data, when you want to make a call it MAY redirect onto 3G to make the call, which may be from a different cell or a different frequency (or both). Both of which may mean you go from low 4G strength to high quality phone call. You could simulate this by turning off 4G (if you can??).

Also, Sony’s support more frequencies than some other makes. Therefore the operator MAY be pushing you onto a frequency that your old phone did not support – therefore suggesting that your new phone has weaker signal.

Each vendor implements the signal strength meter in their own way. Mostly just rssi based (which has nothing to do with how the base station hears you, its purely based on how your mobile “hears” the network)