TDM/FDM or CDMA

[sympton]

I am just wondering most of the cell phones, what kind of algorithms use from following list.

TDM
FDM
CDMA

Which is more relaible and secure.

thanks
sympton

[SQNWK]

The future with 3G is going to be CDMA

[bex]

I would say the future 3G would be CDMA and maybe OFDM. OFDM is a FDM access technique that is used in WiMAX and known to be a candidate for future "super 3G" and 4G. There are pros and cons with all access techniques, but in general you can get a better spectrum utilization if OFDM is used (higer bps/hz value). Which technique that is more reliable depends on the application.