detect cell phone ring signal

http://www.epanorama.net/circuits/telephone_ringer.html

Thanks dv_sa559
but i don't want to detect the telephone ring signal i want to detect cell phone ring signal

Cellular Phone calling Detector
http://www.redcircuits.com/Page47.htm

What receiver are you using to detect the ring from your cell phone?
if you use uController, you just simply use one transistor of the buzzer or vibra cell phone

Please can you give more detail about one transistor of the buzzer ?

I ever made a phone interface project using CDMA or GSM cellphone, which I normally use Nokia, Kyocera, Ericsson, .. when a incoming buzzer issued a logic low output with the ring volume requirements should be maximal

For this he must open phone and make connection. Of course and this is one of the solutions, why not.

hello
is there any approach to find only the ring signal detector?

How do you mean only ring signal detector ?

In my post #4 circuit will detect ring signal. Led will blink few sec before phone start ringing.

This certainly is one way of many ways that might help him for consideration and appropriate project that he created.

Yes I agree with that.

As you know the data send in some packets and this circuit detect the energy of these packets.while ringing and speaking to cell phone you see the output of that circuit always blink.and not detect only the ring signal

When phone is in standby, no call active, what can happen? First ring then activate call.

This is simple circuit try it. When establishing call (ringing), power of signal is different.

Thanks
i will check it

There's no easily detectable ring signal in GSM communication. The shown circuit can be considered as "RF activity" indicator. It will trigger when the phone acknowledges incoming calls, but also on housekeeping data exchange with GSM base station, sending/receiving SMS and other activities. No chance to detect calls selectively.