Happens often to me
your phone is broken? idk never happened to me. you jailbroken and install somthing?
I'm not jailbroken and this happens to me. I even have the magical
http://wps.ncs.gov/ active on my phone due to my job. This would be an interesting attack, but likely not have the planned impact. Cellular networks turn down the radio power as they see more 'active' users within the cell.
Best thing AT&T could do to help with these issues would be to launch the microcell nationally, or ship one to every iPhone user that has dropped calls. Apple (at least) gets the intelligence for the number of dropped calls fed into their feedback system from the phone diagnostic data.
eg:
Library/Logs/CrashReporter/MobileDevice/Jared Mauchs iPhone/Baseband
Check out the contents of the *-stats.txt* files.
When you see the phone drop several times in a 10-15 minute period, here in the good ol midwest, it's not something just seen in NYC/SFO. Phone works fine when I am in Japan on a pure UMTS 3G network..
11:51:45 -0500 ST [clm] disconnect: duration=1227;cause=kNoNetworkService;ceer=355;txPower=13;maxTxPower=24;txPowerLimitType=1;rat=2;cgi=310:410:26507:34749
11:52:10 -0500 ST [rm] reset: reason=call drop;uptime=95993;count=3;callactive=true;pdpactive=false/false/false/false;rat=0
12:05:02 -0500 ST [clm] disconnect: duration=769;cause=kNoNetworkService;ceer=355;rat=0;cgi=310:410:26009:10717
12:05:12 -0500 ST [rm] reset: reason=call drop;uptime=96776;count=3;callactive=true;pdpactive=false/false/false/false;rat=3
12:08:31 -0500 ST [clm] disconnect: duration=187;cause=kNoError;ceer=0;rat=0;cgi=310:410:26009:10717
12:15:06 -0500 ST [clm] disconnect: duration=300;cause=kNoError;ceer=0;rat=0;cgi=310:410:26507:34289
16:39:39 -0500 ST [rm] reset: reason=modem reset: +xlog=4 rsp is err;uptime=113257;count=4;callactive=false;pdpactive=false/false/false/false;rat=2
16:39:39 -0500 ST [rm] crash: state=Resetting