Abstarct: Nowadays, sending and receiving data correctly on noise channels is a very important factor in wireless communications. For this reason, error correction codes have been developed. In recent years, fountains have attracted a lot of attention due to the ability to detect and correct errors, and are therefore proposed for the different standards of the new generation of telecommunication systems. In addition to the great advantages of this type of coding, its use in wireless telecommunication systems faces challenges. One of the most important challenges related to the fountain codes, failures of their decoding process is that the decoder in the structure of the error consists of stopping sets, trapping sets and absorbing sets that do not allow the decoding process to correctly recovered the messages. In this thesis, research is carried out on one of the types of Fuuntain codes called LT codes, focusing on absorbing sets. After finding absorbing sets and declaring that the decoder is caught in absorbing sets, a new decoder is designed with the goal of release absorbing sets. The results indicate that the new decoder will improve the realized rate, the cost of the decoding and the performance of the error.