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Titan12

macrumors regular
Original poster
Jun 16, 2009
110
0
Hey Guys,
Ive noticed over the past few days (after testing it out several times) that although my iPhone has full tower, it sometimes wont immediately ring when it is called. On the calling end, I hear the fast ring tone that you normally hear when a phone has low/no tower, then it switches to the normal ring associated with a good connection. This also appears to happen on my wifes phone, as well as my mom's 3G. Could this possibly be due to the iPhones use of Edge data? or even possibly due to push notifications for mobileme, etc...? I was just wondering if anyone else sees this happen from time to time.
 
I'm pretty sure that's how it's always been, at least to my knowledge. You always get the ring to the tower and then the connected to the phone ring ... I may be wrong though.
 
Just tested it from my work phone. I'll hear about a full ring and a half on my end before my iPhone starts ringing. Maybe it's standard for AT&T?
 
Maybe it's standard for AT&T?
Maybe.

When I had my 2G iPhone sitting on the desk next to my speakers I would tend to hear the buzz that you often get with GSM phones. I could heard the buzz start in a certain pattern and knew a call was coming in a second or two before it started ringing. Pretty interesting. Doesn't happen with 3G/UMTS of course.
 
What the heck is that? I'd like to educate myself, lol.

I don't know either ... but this is what Google turned up:

Q In CDMA what is meant by "slot cycle index"? UP

A. [Credit: Bill Walker]
On the CDMA Paging Channel (this is the shared channel that all phones
listen to for incoming calls and other control info), time is divided into
"slots". To conserve power, phones that are currently idle only "wake up"
and listen for messages on the Paging Channel during their assigned
slots. The slot cycle index determines how often the phone's slot comes
around. If the slot cycle index is 0, the phone wakes up every 1.28
seconds. If it's one, it wakes up every 2.56 seconds. If it's two, it's
every 5.12 seconds, and so on. The larger the setting, the more power is
conserved, but the longer it takes to page the phone for an incoming
call. You can imagine that if it were set to 10.24 seconds, few callers
would hang on the line long enough for you to answer your phone.

There are two settings that govern this. One is the "preferred slot cycle
index" in the phone, and can be set via service programming. The other is
the "maximum slot cycle index" set in the base station and broadcast in
overhead messages on the Paging Channel. The phone has to use whichever
number is smaller.
 
Humm looking it up the SCI might just be a CDMA thing. I would assume a GSM phone has the kinda the same thing but will have to research as I'm interested in how GSM works with this. The SCI is how frequently the phone would check with the tower if a call was coming in or not so if a call came in right after it checked it would take the whole SCI before it saw a call was hitting a ringing. The benefits of a longer SCI was suppose to be a better battery life as the phone wasn't checking with the tower as much.
 
Humm looking it up the SCI might just be a CDMA thing. I would assume a GSM phone has the kinda the same thing but will have to research as I'm interested in how GSM works with this. The SCI is how frequently the phone would check with the tower if a call was coming in or not so if a call came in right after it checked it would take the whole SCI before it saw a call was hitting a ringing. The benefits of a longer SCI was suppose to be a better battery life as the phone wasn't checking with the tower as much.

That does sound very interesting, and would make sense as an explanation for what I'm experiencing. The reason I was leaning towards Edge as the culpret was the fact that the fast ring I hear is the same as the ring I get when I try and call my wife and she is browsing the web over Edge... the call rings fast and never connects.
 
I hear the fast ring tone that you normally hear when a phone has low/no tower, then it switches to the normal ring associated with a good connection.

What's this fast tone with no tower and normal ring with good tower? I've never noticed different ringing?
 
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