Cdama communication base station interferance

In cdma systems base station recive a lot of msgs from mobile users at same time ,same frequency and same power. How can base station frontend can understand a signal?

CDMA came from Code Division Multiple Access.
Each mobile use different code and the base station is able to differentiate the users by their code (and not by power, time, etc.)

Still i have some doubt... same frequency data will add or sub? If they combine then reciver only gets only one code that may the sum off all code?

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http://www.bing.com/search?q=explana...onid=&pc=EUPP_