基于LDPC的MIMO卫星扩频通信系统

摘要

MIMO technique, namely the muhiple-input-muhiple-output technique, is widely used in various communication systems as it can enlarge channel capacity. In satellite communication systems, there are mainly two problems, co-channel interruption and noise, confronting MIMO application. In this paper, the MIMO linear de- tection system used in satellite communications aiming at overcoming co-channel interruption is introduced. Sprea- ding and the Shannon-limitation-approaching LDPC encoding are introduced at input, while at output dispreading and decoding are done. Thus, both the co-channel interference and noise are significantly reduced and a good perform- ance for this system is reached.%MIMO即多输入多输出通信技术,因其可以增大信道容量,而被广泛应用于各类通信系统中。在卫星通信系统中应用MIMO技术,主要面临同道干扰和噪声两个问题。文中介绍了克服同道干扰的MIMO卫星通信线性检测系统,并为解决上述问题,在输入端引入扩频技术和接近香农极限的LDPC编码,而在输出端进行解扩和译码,既减小了同道干扰,又明显削弱了噪声,从而实现了良好的性能。