CDMA is a multiplexing technique on the basis of set of orthogonal codes. CDMA is complex compared to traditional multiplexing technique yet CDMA has become the preferred choice of multiple access air interfaces in mobile telephone. This project aims at implementing code division multiplexing in hardware level, during the initial phase. In the final phase a simulation based study of CDMA system was performed. This report presents the detailed description of work carried out within project duration and the results obtained. Implementation of Code Division Multiplexing in FGPA has been successfully accomplished and the report explains in depth, the system design, implementation in VHDL, synthesis onto an FPGA and verification process in detail. Similarly, the simulation of CDMA system in MATLAB has also been completed with some limitations. The report describes the simulation model used and the analysis of results obtained. A robust multiplexing technique is imperative to serve multiple users over a common air interface channel in mobile communication. TDMA and FDMA are two traditional multiple access schemes and are used in GSM. A new multiple access technique based on identifying a unique user based on a set of orthogonal codes is called Code Division Multiple Access (CDMA). CDMA uses code division multiplexing (CDM) technique which is based on mathematical concept of orthogonal codes. CDM allows all users to share a common time and frequency domain and yet be uniquely identified on the basis unique codes. CDM technique proves to be advantageous over TDMA and FDMA techniques is becoming the preferred choice of multiple choice air interfaces in future generations of mobile technology. The IS-95 cellular mobile system from Qualcomm was the first system to use CDMA as the multiple access technique in mobile telephony. CDM is complex technique compared to TDMA and FDMA. Further, intuitive understanding of CDM is difficult due to mathematical theory involved. However this technique is proved to be more spectrally efficient, increased capacity and secure compared to prevalent technologies. The commercial popularity of CDM technology in mobile telephony has made CDMA an important technology. This project aims at understanding this very multiplexing technology. In the initial phase operation of CDM was implemented at hardware level. In the final phase a theoretical simulation study of CDMA based communication system under different operational conditions was performed.

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