Novel distributed UEP rateless coding scheme for data transmission in deep space networks

In deep space data transmission systems, deep space networks can be constructed on different orbits, and the data from each orbit are always associated with the different reliability requirements. In this study, a novel UEP (unequal error protection) transmission scheme based on distributed LT codes is proposed in order to ensure that all the data can be transmitted according to their own reliability requirements and obtain high transmission efficiency property. In the proposed scheme, the sub-codes on each node (orbits) were performed by a classic LT encoding process. By assigning different degree distributions to the sub-codes, all types of data can be transmitted with better transmission efficiency in comparison to the traditional scheme, and can be recovered at the destination with their own reliability requirements. Moreover, the design of the proposed scheme is much easier than that of the traditional scheme, and is also suitable to the strictly limited processing capacity property of deep space networks. By carrying out asymptotic analysis on the proposed scheme, and by obtaining the numerical and simulation results, it can be seen that the proposed scheme can approximately achieve the same UEP property and much better transmission efficiency than the traditional scheme. Additionally, the results demonstrate that the proposed scheme is much more suitable to deep space network data transmission, in comparison to the traditional scheme.