Recognize DTMF tones in downlink

[heuven]

Hi,

would it be possible to recognize DTMF tones in the downlink using APS? How to (start) develop such a component?

To be clear: I do not want to send DTMF tones. I want to receive and recognize them!

BR,

Rene

[symbianyucca]

Here's couple of older threads on the topic:
http://discussion.forum.nokia.com/fo...DTMF+recognize
http://discussion.forum.nokia.com/fo...d.php?t=144166
http://discussion.forum.nokia.com/fo...t=receive+DTMF

[arijr]

Applied Goertzel algorithms are suitable for that job and are widely used in various points e.g. in telecom networks and functions. The topic has been widely covered in numerous DSP textbooks and a lot info can be found from the internet and Usenet groups.

Have a look in here, includes a demonstrative C source:

http://en.wikipedia.org/wiki/Goertzel_algorithm

BR,

-Ari

[lming]

I think that there is no public api to detect DTMF tones
probably you need to implement your own component to detect DTMF by using Goertzel Algorithm

[heuven]

Hi,

thanks! That answer sounds very reasonable and helpful. Will have a look.

BR,

Rene