文档介绍：摘要
智能天线是近年来移动通信领域中的研究热点之一,应用智能天线技术可以很好地解决频率资源匮乏问题,可以有效地提高移动通信系统容量和服务质量。开展智能天线技术以及其中的一些关键技术研究对于智能天线在移动通信中的应用有着重要的理论和实际意义。但当天线接收信号存在主瓣干扰时,利用自适应波束形成技术抑制干扰会暴露出两个缺陷:一是副瓣电平增高;二是主波束变形且峰值偏移。
当存在主瓣干扰且有期望信号混入情况下,用常规自适应波束形成方法进行自适应干扰对消,不但会引起主瓣变形,而且期望信号也会被抑制,从而影响对消性能。本文提出一种新的阻塞矩阵方法,对接收数据进行预处理,消除它们对计算数据协方差阵的影响,再用其它方法确定自适应权值。理论分析和计算机仿真表明,用阻塞矩阵方法可以获得较大的性能提升。
关键词
智能天线;主瓣干扰;自适应波束形成;阵列信号处理
Abstract
In recent years,Smart Antenna,which is considered to be a solution to the problem of lacking frequency,es a hotspot in the munication area. With this technology,Capacity of munication system can be increased effectively and the quality of service can be improved at the same time. To study Smart Antenna and its key technologies is important both in theory and in practice. There are two disadvantages in adaptive beam forming in the presence of main lobe interference, one is heightening of side-lobe level, the other is distortion and peak offset of main beam.
When target signal is in the sample data, the performance of adaptive digital beam former (ADBF) will be degraded. If the interference falls into main lobe, the main beam will be distorted with conventional ADBF. A new block matrix (NBM) method is proposed which preprocesses the sample data via a block matrix so that the influence of signal-of-interest (SOI) and main lobe jamming is diminished. This method avoids main lobe distortion and has the better performance of interference cancelling than the direct sample matrix inversion (SMI) method. The results of simulation support the theoretical predictions.
Key words
Smart antenna; Adaptive beam forming; Main lobe interference canceling; Array signal processing
目录
摘要 Ⅰ
Abstract Ⅱ
第1章绪论 1
1
2
3
4
4
5
6
7
第2章智能天线 8
8
8
9
9
10
自适应波束形成算法 12
第3章基于阻塞矩阵的主瓣干扰抑制算法 14
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15