CDMA - Incoming Call Indication

[priyarajan]

Hi All,

I recently brought a mobile-holder which glows when calls come in.
I accidentally found that this feature was seen only with GSM phones and not with CDMA mobiles.

What may be the reason for this?

[carcomptoy]

Because GSM is way better...sorry I just had to say that. Honestly, I don't know...everywhere you see the flashing antennas and batteries etc. it always says will not work with Verizon and blah blah blah. Actually, I'm very interested as to knowing why it won't work either...

[psykon99]

I'm not positive on this, but if I remember correctly from my TDMA days, TDMA and GSM networks send a separate "ring" signal to a phone aside from the actual call itself. This "ring" signal is what the phone holders use to know when to flash.

Either CDMA does not have a separate "ring" signal to trigger the phone holder, or if it does, it's on a different frequency band than TDMA / GSM.

Sorry, that's the best I can do. It was sooo long ago. :)

[carcomptoy]

Ah that makes sense...I would think though that it's not the frequency band because don't GSM and CDMA use the cellular and PCS bands, at least in the US?

[psykon99]

Ah that makes sense...I would think though that it's not the frequency band because don't GSM and CDMA use the cellular and PCS bands, at least in the US?


Yea, they use 800 and 1900. But the "ringer" signal, if CDMA has one, is not necessarily broadcasting on the same specific band range that the TDMA/GSM standard is. Know what I mean?