Analysis and Development of Algorithms for Antenna Array Based Communications Systems

在多个同频道信号同时存在的情况下，需要使用天线阵列的通信系统。由多个天线单元提供的空间辨别允许单独提取频谱重叠的信号。虽然这类系统通常是在军事应用的背景下提出的，但一些重要的商业应用最近得到了关注。特别是，有人建议在陆基移动无线电系统中使用天线阵列，以提供增强的空间分辨能力，从而增加容量。这样的阵列可以潜在地在相邻小区中或在通信小区本身内提供频率重用。这项研究正在使用天线阵列检查信号复制、干扰消除和信源定位，特别强调在移动无线电通信中可能遇到的场景(例如，多径衰落环境、某些信号格式，例如模拟FM IS-3 AMPS、GSM、IS-54偏移量QPSK、IS-95 CDMA等)。这项研究的一个重点是开发和分析利用所有可用的时间和空间信息的算法。用于测向(DF)和信号复制(SC)的传统技术依赖于数据中的空间结构或时间结构，但通常不是两者都依赖。在阵列响应数据和有关信号结构的信息都可用的情况下，忽略两者显然都不是最优的。因此，将研究几种利用空间和时间信号结构来改善DF/SC的不同技术：迭代盲最小二乘法；基于阵列的判决指导算法；以及具有参数阵列不确定性的最优联合DF/SC。最后，本研究将特别强调使用真实的移动蜂窝无线数据来测试所开发的算法的有效性。

Communication systems employing antenna arrays are required in situations where multiple co-channel signals are present simultaneously. The spatial discrimination provided by multiple antenna elements allows spectrally overlapping signals to be individually extracted. While such systems have typically been proposed in the context of military applications, a number of important commercial applications have recently gained attention. In particular, it has been proposed that antenna arrays be used in land-based mobile radio systems to provide enhanced spatial discrimination and hence increased capacity. Such arrays could potentially provide frequency reuse in adjacent cells, or within a communication cell itself. This research is examining signal copy, interference cancellation, and source localization using antenna arrays, with particular emphasis on scenarios that might be encountered in mobile radio communications (e.g., multipath fading environments, certain signal formats such as analog FM IS-3 AMPS, GSM, IS-54 offset QPSK, IS-95 CDMA, etc.). A focus of this research is the development and analysis of algorithms that exploit all available temporal and spatial information. Conventional techniques for direction finding (DF) and signal copy (SC) rely on either spatial or temporal structure in the data, but typically not both. In situations where both array response data and information about the signal structure is available, it is obviously suboptimal to ignore either. Consequently, several different techniques that exploit both spatial and temporal signal structure for improved DF/SC will be studies: iterative blindleast-squares; decision directed algorithms array-based equalization of multipath channels; and optimal joint DF/SC with parametric array uncertainty. Finally, special emphasis will be placed in this research on the use f real mobile cellular radio data to test the effectiveness of the algorithms developed.