中文摘要：

针对深空通信中时延长、误码率高、信道非对称及短码长LT码冗余度高、译码成功率低等问题,提出一种基于优化LT（OLT）码的深空数据传输策略。首先通过调整度分布函数、采用新颖的数据包选择策略以及联合译码算法,提出OLT码。然后,提出基于OLT码的深空数据传输策略：发送端对数据文件进行OLT码编码并发送;在接收端,使用联合译码算法对接收到的编码包进行译码得到原始数据。仿真结果表明,与LT码相比,OLT码能够提高译码成功率并降低冗余度;与CFDP相比,该策略可以有效降低时延,提高数据传输的有效性和可靠性;在高丢包率的情况下,该策略的优势更加明显。

英文摘要：

Focusing on the shortcomings such as long delay, high Bit Error Rate（ BER）, asymmetric channel in deep space communication, high redundancy and low decoding success rate of short LT codes, a new deep space data delivery strategy based on Optimized LT（ OLT） codes was proposed. First, the OLT codes was given by adjusting the degree distribution function, and adopting new packet selection strategy and joint decoding algorithm. Then, a deep space data delivery strategy based on OLT codes was presented, in which the sender encoded the data file and sent it out, and the receiver got the data by decoding the encoded packets by use of joint decoding algorithm. The simulation results show that compared with LT codes, OLT codes can improve decoding success rate and reduce redundancy. Besides, compared with CFDP, the proposed strategy can effectively reduce the delay and improve the validity and reliability of data delivery,especially in the case of high packet loss rate.