The purpose of the software is to provide an environment for evaluation of the performance of both fixed and adaptive multiuser detectors for DS-CDMA. The nature of modern communications is complicated enough without introducing multiple users using the same bandwidth in a highly time varying system. Each user in the system has their own channel characteristics, timing, power, and spreading code, which means there are a lot of parameters which need to be specified to generate somewhat realistic data. There are also multiple ways of comparing the performance of different receivers, including output mean squared error, bit error rate, etc. So the problem becomes, ``How can you make software to simulate a multiuser system without overwhelming the user with options, but still obtain reliable and useful results?''. Also, due to the continuing research in the field of multiuser communications, the software needs to be upgradeable so new designs can easily be implemented and tested. The requirements can be listed as follows,
Given these requirements, we first need to decide on the tools needed to implement such a software package. There are many software packages available to develop GUI's, but not so many lend themselves to signal processing as much as Matlab. Matlab's signal processing and communication functions and graphical nature were the reason for choosing it as the programming language. The graphical user interface tools are also well documented and easy to use. Using a C based program would have resulted in faster simulations, however, the development time would have been much more extensive. It should be noted that Matlab functions can be implemented in C code for faster performance.