The GSM platform is a extremely successful wireless technology and an unprecedented story of global achievement. The GSM platform is growing and evolving and offers an expanded and feature-rich voice and data enabling services. General Packet Radio Service, (GPRS), will have a tremendous transmission rate, which will make a significant impact on most of the existing services. Additionally, GPRS stands ready for the introduction of new services as operators and users, both business and private, appreciate the capabilities and potential that GPRS provides. Services such as the Internet, videoconferencing and on-line shopping will be as smooth as talking on the phone. Moreover, the capability and ease of access to these services increase at work, at home or during travel. In this research the traffic channel of a GSM system was studied in detail and simulated in order to obtain a performance analysis. Matlab, software from Mathworks, was used for the simulation. Both the forward and the reverse links of a GSM system were simulated. A flat fading model was used to model the channel. Signal to Noise Ratio, (SNR), was the primary metric that was varied during the simulation. All the building blocks for a traffic channel, including a Convolutional encoder, an Interleaver and a Modulator were coded in Matlab. Finally the GPRS system, which is an enhancement of the GSM system for data services was introduced.