Performance and Complexity of CDMA Networks With Coded Modulation

众所周知，扩频多址系统的最佳解调器是极其复杂的，除了在非常有限的用户数量下实现是不实用的。一些次优的接收器已经被发现达到了接近最优的性能（在没有编码的情况下），并且大大降低了复杂性。此外，众所周知，对于扩频系统，编码可以显著改善干扰和多址环境下的性能。该项目是对编码扩频多址系统性能的研究，该系统具有各种类型的接近最优，但降低了复杂性，解码器和解调器。其目的是设计降低复杂性的解码器和解调器，以实现复杂性和性能的有利权衡。

The optimum demodulator for spread-spectrum multiple access systems is known to be extremely complex and not practical for implementation except for a very limited number of users. Several suboptimum receivers have been found to achieve near optimal performance (in the absence of coding) with much reduced complexity. In addition, it is known that for spread-spectrum systems coding can significantly improve the performance in a jamming and multiple-access environment. This project is an investigation of the performance of coded spread-spectrum multiple-access systems with various types of near optimal, but reduced complexity, decoders and demodulators. The aim is to design reduced complexity decoders and demodulators that achieve a favorable tradeoff in complexity and performance.