基于交叉极化的混合双工方法

全双工技术使得信号的发送和接收可以同时同频进行而提升了频谱利用效率。与此同时,信号的同时同频发送和接收使得发送链路对接收链路造成较强的自干扰问题。自干扰消除使得信号收发器的结构较为复杂,而不适用于移动终端设备。提出了一种基于交叉极化的混合双工通信方法,该方法基于交叉极化-频率资源进行干扰隔离。由于频率和交叉极化本身具备一定的正交性,因此不需要复杂处理而降低移动设备端的复杂度。此外,基站端可以承受较高的复杂度而按照用户的距离对交叉极化资源进行分配,以弥补交叉极化正交性不理想的缺陷。仿真结果表明,相比完全全双工以及完全半双工的通信方法,提出的混合双工通信方法在降低实现复杂度的同时,可以保证较高的小区平均吞吐量。     

交叉极化对单脉冲雷达角度欺骗干扰仿真分析

介绍了单脉冲雷达的特点及工作原理,针对单脉冲测角雷达体制,提出并分析了对单脉冲雷达角度跟踪系统的交叉极化干扰。通过仿真,对交叉极化干扰的效果进行了讨论,指出交叉极化干扰是实际工程中一种较为可行的干扰方式。     

交叉极化干扰作战效能分析

系统地分析了交叉极化干扰对单脉冲雷达的干扰效果,详细分析了交叉极化干扰对防空导弹系统的中制导截获概率和末制导命中概率的干扰效能,通过理论分析和数字仿真,得到了交叉极化干扰能够使中制导截获概率降低到20％以下,使末制导命中概率降低到30％以下的结论.在此基础上,提出交叉极化干扰在未来电子对抗系统的应用前景.     

交叉极化鉴别率和交叉极化干扰抵消技术在实际中的应用

同频正交极化频率复用技术是提高微波接力系统传输容量的非常有效的手段之一,传输系统的交叉极化去耦度(XPD)及自适应交叉极化干扰抵消技术(XPIC)是系统抗交叉极化干扰的主要措施,本文列举了工程实测数据从实现方法及对干扰中断率的改善等方面进行了分析.     

高速数传中的交叉极化干扰对消设计

给出一种适用于高速数传解调器中的交叉极化干扰对消的方法。首先通过主信号的解调环路信息对干扰信号进行下变频和重采样,提取基带干扰信号,然后通过自适应算法调整滤波器系数,抵消主信号中的交叉极化干扰分量。仿真结果表明,该方法可适用于不同载波频率、不同调制方式、不同符号速率间的信号交叉极化干扰,有效减少交叉极化干扰带来的误码率恶化。     

交叉极化鉴别率和交叉极化干扰抵消技术在实际电路中的应用

同频正交极化频率复用技术是提高微波接力系统传输容量的非常有效的手段之一，传输系统的交叉极化去耦度（XPD）及自适应交叉极化干扰抵消技术（XPIC）是系统抗交叉极化干扰的主要措施，本文列举了工程实例数据从实现方法及对干扰中断率的改善等方面进行了分析。     

基于ICA的交叉极化干扰抑制算法

针对极化复用模式中引入的交叉极化干扰问题，利用一种基于独立成分分析（ICA）的盲分离算法，无需信号先验知识和后续解调即可从观测信号中分离出源信号，达到消除极化干扰的目的。该算法基于线性瞬时混合模型，对峭度对比函数进行精确线性搜索优化，选取最佳步长，解决了盲分离信号中的排序问题。文中对不同信噪比和极化隔离度下的分离效果进行了仿真，仿真结果表明，该算法具有较好的分离性能，且在强交叉极化干扰和低信噪比下的性能较为稳定。     

交叉极化干扰工程边界条件分析

深入讨论了交叉极化干扰的工程化问题,详细分析了自适应交叉极化信号产生的天线极化特性和幅相控制要求,阐述了该技术工程实现方面的边界条件,对该技术在实际装备的应用提供了指导意见。通过理论分析和相关计算表明:如果能将通道相位和幅度误差分别控制在*6°、*0.5d B,就能够满足交叉极化干扰的控制要求。     

小椭圆度圆波导的交叉极化效应

引用线性代数理论，详尽分析了小椭圆度波导的交叉极化效应。指出了消除其交叉极化效应的途径。实验表明，理论与实验非常吻合。     

基于复数FastICA的双极化干扰对消算法研究

为解决卫星通信中极化复用导致的交叉极化干扰问题，提出了一种基于复数快速独立成分分析方法，根据传输信道的对称性对算法作了简化处理，减少了计算量。该算法依据发送端的两个线极化信号的不相关性，在无源信号及混合矩阵的先验信息情况下，构造负熵函数并使其最大化来分离出独立成分，进而实现交叉极化信号对消。仿真实验以正交相移键控调制信号为例，从误差向量幅度、信干噪比、交叉极化隔离度、性能指数这几个指标上进行仿真，仿真结果显示基于复数快速独立成分分析方法对解决交叉极化干扰问题具有良好的性能。     

Evaluating the Use of Cross-Polarization Discrimination in Mitigating Interference from Unlicensed Devices onto DTV

This paper presents the results of the tests performed by the Communications Research Centre Canada (CRC) for determining cross-polarization discrimination of some consumer-grade UHF TV antennas that are available on the market. The test conditions were selected to resemble the situation when a UD (Unlicensed Device) transmitting antenna is operational in the vicinity of a TV receiving antenna. The results of this experiment will be helpful in evaluating the effectiveness of cross-polarization discrimination when it is used as a way of mitigating the interference effects from UD radiation onto DTV reception.      

一种针对旁瓣消隐雷达的假目标干扰方法

旁瓣消隐技术是现代防空雷达中常用的一种空域抗干扰措施,其对脉冲式欺骗干扰的抑制尤为明显。为了最终形成航迹欺骗干扰,文中在研究旁瓣消隐系统的工作原理基础上,采用交叉极化干扰突破旁瓣消隐系统来形成假目标,利用旁瓣消隐雷达假目标检测概率作为评价指标来分析干扰效果,还分析了极化正交性及干扰功率对干扰效果的影响,最后通过仿真验证了这一方法的有效性。     

正交偶极子的极化特性分析

双极化相控阵天线的极化特性及其对目标极化散射矩阵测量的影响,将决定相控阵体制雷达获取目标极化信息的精度和能力,是相控阵雷达极化技术的基础。以正交偶极子为阵元模型,分析了双极化阵列天线的空域极化特性及其对雷达目标极化散射矩阵测量的影响。由于两阵元辐射电场在偏离视轴方向的非正交性,不可避免地会引起两天线交叉极化之间的相互干扰。根据传统交叉极化评价指标的定义,分析了正交偶极子天线的交叉极化特性,并从目标极化特性测量性能的角度,定义了双极化雷达系统的交叉极化隔离度,将其表示为极化测量系数矩阵条件数的形式,以衡量全极化相控阵雷达天线的交叉极化特性。     

System Implications of 14/11 GHz Path Depolarization. Part II: Reducing the impairments

Dual-polarized co-channel operation via international communications satellites places stringent requirements on the amount of interference that can be allowed from all sources. System design must allow for the depolarization caused by rain and ice crystals, the principal source of additional interference. In the 14/11 and 14/12 GHz bands, some paths are depolarization limited, particularly at lower path elevation angles, or become so with up-link power control. Others are attenuation limited. Therefore, a means must be found to reduce the level of path depolarization to meet the requirements for path availability. In Part I or this paper, reference joint statistics of cross-polarization discrimination/attenuation statistics were derived for a number of paths and climates to establish the additional fade and cross-polarization discrimination margins required. This second paper addresses methods for reducing the system effects of path depolarization. Appropriate orientation of the polarization vectors at the spacecraft is shown to be an attractive alternative for spot-beam applications. For all other situations, it is concluded that single-parameter, phase-only compensation at the earth terminal will meet all practical system requirements.     

微波SDH关键技术

本文简要介绍了ＳＤＨ数字微波传输系统中采用的几 项关键技术：高性能高速多状态调制解调技术;自 适应交叉极化干扰抵消技术;前向纠错技术;自适 应对抗多径衰落技术;自适应发信功率控制技术。     

Digitalized Cross-Polarization Interference Canceller for Multilevel Digital Radio

This paper proposes a newly developed, highly precise cross-polarization interference canceller (XPIC), utilizing digitalized transversal filters. Performance of the digitalized XPIC is solely determined by quantization and tap numbers and is not affected by any circuit imperfection. Moreover, it can be universally applied to different bit rates and various modulation schemes. Performance of the XPIC is analytically estimated for various modulation schemes and various interference conditions. Then, the digitalized XPIC is realized and applied to a 12.5 MB 256 QAM digital radio system. Experimental results have closely conformed with theoretical estimations and it is confirmed that the XPIC is a powerful countermeasure against multipath fading for a future digital radio.     

A Terrestrial Rain Depolarization Compensation Experiment at 11.7 GHz

Depolarization caused by rain at 11.7 GHz is due to both differential phase shift and attenuation. In dual polarized communications systems it gives rise to interference which may be severe enough to cause an outage even though the allotted fade margin has not been exceeded. Described is a depolarization compensation experiment over a 10 km path with near circular polarization at 11.7 GHz. It made use of a turnstile junction feed system under computer control. Data presented demonstrate the stable performance of the method used during several rain events. At fades below about 15 dB significant isolation improvements were achieved, compared to a fixed cross-polarization channel. Finally, a method using the turnstile is suggested to receive two nonorthogonal signals without interference.     

单元交叉极化对自适应阵列性能的影响

该文分析了在存在双极化干扰机条件下的自适应阵列的性能，由于接收天线单元交叉极化方向图不一致性的存在，通过改变两正交极化干扰分量之间的相位，可以导致阵列单元之间的幅相不一致发生变化，这种变化是无法用简单的校正固定幅相误差的方法来加以校正的，从而导致自适应阵列的性能下降。     

A simple polarization-recovery algorithm for dual-polarizedcellular mobile-radio systems in time-variant faded environments

Dual-polarized signaling constitutes an effective frequency-reuse technique to enhance the cell capacity in cellular mobile-radio systems. In the present paper, we present a new cross-polarization interference canceler (XPIC) which accomplishes the polarization-recovery task in time-division multiple-access (TDMA)-based cellular radio systems. The main new attractive feature of the proposed XPIC is that it is able to work even in the presence of unknown and possibly time-variant random phase fluctuations, as those due to imperfect phase recovery at the receiver side