【作者】 于蕾；

【导师】 杨莘元；

【作者基本信息】 哈尔滨工程大学 ， 通信与信息系统， 2004， 硕士

【摘要】 论文介绍了目前在通信和信号处理领域研究的热点之一—自适应波束形成算法的基本的技术形成、原理、历史发展和远景目标。盲自适应波束形成以其不需要参考信号的优点，成为近年来众多学者的研究热点。本文主要研究了盲自适应波束形成中的一类重要的算法—恒模算法。 恒模信号是一类非常重要的通信信号，尤其在CDMA通信系统中，大多数信号都是恒模信号。而专门应用于恒模信号的恒模算法具有计算复杂度较低，实现起来比较简单，对阵列模型的偏差不敏感等显著的优点。因此，恒模算法引起了众多学者的广泛关注。本文系统的研究了恒模算法的收敛性能，通过仿真表明恒模算法的收敛性能很好，在波束形成领域中的应用是很有潜力的。不仅如此，恒模算法在其它领域中的应用也颇受关注，例如在通信过程中利用恒模算法消除多径干扰和消除共信道干扰的研究取得了较好的效果。但是恒模算法的缺点在于步长因子的选择不好将导致算法发散及无法识别多路恒模信号，论文在此基础上研究了最小二乘恒模算法和多级恒模算法。 但是我们也清楚地看到恒模算法以及其它的盲波束形成算法仍然处于不断发展和完善的过程中，受系统处理速度所限，他们还不能应用于实际的自适应天线系统中。更多还原

【Abstract】 The paper introduces one of the hottest spots in the communication and signal processing fields, adaptive beamforming algorithm’ s basic technology, principle, history development and future. Because of its merits that do not need reference signal, blind beamforming algorithm has becoming the research goal of many specialists and scholars in the world. The paper major in researching one kind of important algorithm in the blind beamforming-the constant modulus algorithm.The constant modulus signal is one kind of the more important communication signals. Especially in CDMA system, most signals are constant modulus. And the constant modulus algorithm(CMA), which is used special of the constant modulus signal, has so many marked merits that easily computing, simply realized, unsensitivity to the error of the array model. So CMA has drawn more and more attention of the scholar of the world. The paper study systemicly the convergence behavior of CMA. Emulation shows that the performance of CMA is good. The paper presents the algorithm of LS-CMA and muticonstant algorithm on the base of CMA.But we should now that CMA and other blind beamfarming algorithms are still in developing, and they could not used in real adaptive array system due to the speed of system processing.更多还原