Today's communication systems should allow multiple users to communicate at the same time, specifically when used as cellular networks, radio data this is done with different techniques, these techniques are known as Access and allow a certain number of users to communicate simultaneously, using the channels available. There are three types of basic access techniques: FDMA (Frequency Division Multiple Access), TDMA (Time Division Multiple Access) CDMA (Code Division Multiple Access). This article will try DSSSCDMA technology, which modulates in time frequency, assigning a code to each user, to use the same frequency spectrum. Initially in this paper provides a conceptual review of the techniques listed above then a simulation with MATLAB tool of encoding decoding technique using DSSS-CDMA