Signal Processing in CDMA
CDMA is a multiple-access scheme based on spread-spectrum communication techniques. It spreads the message signal to a relatively wide bandwidth by using a unique code that reduces interference, enhances system processing, and differentiates users. CDMA does not require frequency or time-division for multiple access; thus, it improves the capacity of the communication system. 
As CDMA systems reach capacity, infrastructure providers are extending them by offering multicarrier capability. The capacity of an n-carrier CDMA system should be at least n times the capacity of a single-carrier system. We can estimate the additional capacity that can be achieved by using carrier assignment disciplines. We can also produce the estimates from the CDMA system simulator by preprocessing the simulator inputs and post-processing its outputs. The capacity estimates of multicarrier systems can be made using simple carrier assignment disciplines, and of wideband CDMA systems. The latter estimates constitute an upper bound on the capacity of a multicarrier system with any carrier assignment discipline.