TD-SCDMA和PHS系统干扰共存初探

本文利用确定性分析方法,研究TD-SCDMA和PHS系统间干扰共存问题.通过计算得出各种干扰情况下2个系统之间需要的隔离损耗,并针对工程实施中经常使用的几种解决干扰问题的方法,进行详细的分析讨论,这些将对TD-SCDMA无线网络工程实施提供有价值的参考.     

TD LTE与TD-SCDMA及GSM干扰共存的研究

采用确定性分析方法,研究TDLTE与TD-SCDMA及GSM系统之间干扰共存问题,通过分析计算出各种干扰情况下系统之间需要的隔离损耗,并就工程实施中经常使用的几种解决干扰问题的方法进行分析。     

2GHz频段移动通信系统间干扰隔离分析

首先在介绍干扰分析原则的基础上,重点阐述了采用确定性方法计算采用2GHz频段的WCDMA、cdma2000、TD-SCDMA和GSM 1800系统间共存(共站)干扰隔离,并给出了共存(共站)的简要结论。     

广域覆盖场景中GSM与3G系统间干扰分析

结合山区覆盖特点,对GSM与WCDMA及CDMA1X系统间的干扰情况进行了确定性计算分析,给出了GSM与两系统共存与共站情况下的隔离要求与干扰规避方法。     

固定无线接入系统对卫星地球站的干扰分析

为了使共用同一频段的3.5 GHz固定无线接入系统（FWA）和C波段固定卫星业务（FSS）实现共存,就需要对这两个系统间的干扰进行分析。采用确定性计算方法主要研究了在建筑物密集但排列比较整齐的地形中3.5 GHz固定无线接入系统对C波段卫星地球站产生的同频干扰,给出了同频干扰的计算方法,并进行了仿真分析,从而验证了在这种地形下实现两系统干扰共存的可行性。     

CDMA无线多媒体网络中蜂窝间干扰分析

蜂窝间干扰分析是CDMA无线通信网络中研究的一个重要方面,但干扰分析的传统方法存在3个主要缺陷,不能准确地反映蜂窝系统的实际情况。该文提出了一种新的计算蜂窝间干扰的分析方法,该方法克服了传统方法中存在的3个不足之处。用该方法对蜂窝间干扰进行了定量计算,得到了干扰均值和方差的解析表达式。最后通过数值计算,对不同环境下的干扰进行了分析。结果表明,随着蜂窝间距离的增加,干扰值下降的速率不断减少。     

TD-LTE与TD-SCDMA系统干扰共存研究

TD-LTE和TD-SCDMA系统信号干扰共存一直是无线通信领域的重要研究热点,主要通过结合确定性分析方法研究了TD-LTE和TD-SCDMA系统信号干扰共存的问题。首先介绍确定性分析方法原理;然后详细分析TD-LTE系统基站和TD-SCDMA系统基站相互干扰的影响;最后结合实际施工环境提出解决办法,为日后通信网络施工有效避免信号干扰提供了参考依据。     

223～235 MHz频段离散载波聚合宽带系统频率使用可行性分析

为提高223~235 MHz频段频谱的使用效率,满足行业用户宽带应用需求,在该频段引入了离散窄带载波聚合宽带系统。为解决系统间电磁兼容问题,对宽带系统和带内窄带无线数据传输系统进行了单站干扰分析和集总干扰分析,还对宽带系统和带外广播电视系统进行了确定性计算干扰分析。最后,基于干扰计算结果提出了频率使用的可行性建议。     

TD-SCDMA和WCDMA系统基站的共容分析

主要探讨了WCDMA系统与TD-SCDMA系统基站间的共存问题,并从邻频干扰的角度进行了深入的分析,采用确定性计算方法和静态仿真方法研究TD—SCDMA基站对WCDMA基站产生的邻频干扰,并提出相应的解决方法。     

TD-SCDMA基站和WCDMA基站的共存分析

主要探讨了WCDMA系统与TD—SCDMA系统基站间的共存问题，并从邻频干扰的角度进行了深入的分析；采用确定性计算方法和静态仿真方法研究TD—SCDMA基站对WCDMA基站产生的邻频干扰，并分析了采用智能天线后带来的改善。     

DME系统二次传播路径干涉效应分析

DME 是国际民航组织推荐的近程无线电导航系统，在实际使用过程中，某些覆盖空域可能会出现测距误差超差的情况，经过分析验证，排除无限电干扰因素，主要还是地形反射形成的信号“零区”效应引起的。本文主要通过对 DME 系统二次传播路径干涉效应的分析，对 DME 天线辐射场型的“零区”分布情况进行了分析仿真，为 DME 地面信标的场地选择和天线架设高度提供理论参考。     

移动通信基站信号对空间侦察系统的干扰分析

结合空间侦察系统姿态、波束特性,建立一个近似的波束覆盖基站模型,并通过仿真分析蜂窝移动通信基站信号对空间侦察系统的干扰,特别是干扰功率与侦察角之间的关系、有效干扰基站数目与侦察角之间的关系。仿真结果表明：在一定的条件下,蜂窝通信系统对空间侦察系统的干扰是不容忽视的,甚至是致命的。这对空间侦察系统设计、运行具有一定的参考价值。     

开关电源EMI滤波器设计与验证

开关电源已广泛应用于电力电子设备中,作为一种EMI源,在设计电源电路中需前置EMI滤波器抑制传导干扰。CE102作为检测电源线传导干扰的一项电磁兼容性试验,成为电子设备尤其是军用电子设备的必测项目,测试超标即意味着设计的失败。设计了一个EMI滤波器,通过CE102测试和分析发现并解决设计存在的问题,并通过整改后的试验验证,证明设计的有效性。     

多小区MU-MIMO系统中基于泄露干扰迫零的分布式块对角化预编码设计

该文对多小区MU-MIMO中的预编码设计进行了研究。通过将单小区块对角化预编码进行扩展,将泄漏到邻小区的干扰纳入考虑范围,采用泄露干扰迫零的块对角化预编码,利用发送端提供的额外自由度直接将泄露干扰进行子空间迫零,消除泄露干扰,并且小区内用户之间也进行子空间迫零,消除用户间干扰;从而降低小区间干扰对多用户MIMO系统的不利影响。并且对本文所提算法复杂度进行了定量分析,表明该方案具有较低的计算复杂度。最后通过仿真全面分析了不同参数条件下的系统性能,结果显示该方法能够提高系统的传输速率。      

Optical interference in subcarrier multiplexed systems withmultiple optical carriers

It is shown that, when multiple optical carriers are used in a subcarrier multiplexing system, optical interference noise limits the system bandwidth or the number of available channels. Results of a statistical analysis are presented for a system with multilongitudinal mode semiconductor lasers. The results of the statistical calculations indicate that, when one channel per optical source is transmitted, then the system will be limited to only 16 video-quality channels. However, this number can be increased carefully by choosing and maintaining separate wavelengths for the lasers, in order to minimize the interference noise     

基于FRFT的伪码引信自适应LFM干扰对消方法

该文分析了LFM干扰对伪码引信相关输出的影响,当干扰强度超出伪码引信自身的抗干扰容限时,相关输出严重恶化,因此必须采取相应的抗干扰措施。考虑到LFM干扰与伪码引信有用信号间存在着强的时频耦合,提出了基于FRFT的自适应干扰对消方法。该方法首先对观察信号进行FRFT,估计干扰的特征参数,利用估计出的干扰参数构造自适应干扰对消器,将干扰去除。仿真表明,该方法能够有效滤除LFM干扰,相关输出得到显著改善,该方法对单分量和多分量干扰均有效,不受交叉项影响。     

The Structure of General Interference Functions and Applications

This paper provides a theoretical framework for the analysis of interference-coupled multiuser systems. The fundamental behavior of such a system is modeled by interference functions, defined by axioms “nonnegativity, ”scale-invariance,” and “monotonicity.” It is shown that every interference function has an interpretation as the optimum of a min-max problem, where the optimization is over a closed comprehensive positive coefficient set. This provides new insight into the structure of general interference functions and its elementary building blocks. Conversely, it is shown that every closed comprehensive positive set can be expressed as a level set of an interference function. This shows a close connection between the analysis of interference functions and multiuser performance regions, which are typically closed comprehensive. The generality of this framework allows for a wide range of potential applications. As an example, we analyze the problem of interference balancing.      

Analysis, computation, and mitigation of the interference to aremote receiver from two collocated vehicular transceivers

The widespread use of mobile communications makes the installation of two transceivers in the same vehicle commonplace. This paper presents the analysis, computation methods, and mitigation techniques for the mutual interference caused by two collocated transceivers on a remote receiver. It is, in fact, a complement to a paper presented by Gavan (see ibid., vol.43, no.3, p.447, 1994) that analyzed and computed the mutual interference effects between the two collocated transceivers only. The remote transceiver is less affected by desensitization with increasing separation distances. More important become the effects of single-tone spurious and intermodulation distortion interference, which are thoroughly treated. The qualitative analysis is followed by quantitative computations of the mutual interference effects for a typical VHF/FM-FSK vehicular radio system. Deterministic and semiempirical computation methods are applied and effective mitigation techniques are presented. The presented methods are also efficient for different frequency ranges and modulation methods. Application of these methods by simulation from the initial development phase of new radio systems intended for use in collocated operations will optimize the system performance and improve the frequency spectrum utilization and management     

An Analysis of Average Response Computations Based Upon Aperiodic Stimuli

Average response computation has come to be a widely-used method for the study of evoked potentials recorded from the central nervous system. A mathematical analysis of the mean and variance of the average response computation is presented here. It is shown that an average response computation based upon periodic stimuli will not effectively reduce certain forms of neuroelectric interference. It is further shown that if the stimuli are suitably aperiodic, then the interference can be suppressed.     

Radiometric detection of direct-sequence spread-spectrum signals using interference excision

Direct-sequence spread-spectrum (DS-SS) transmission are difficult to intercept. The theoretical analysis of intercept performance against such systems has always been a difficult task if the noise samples are correlated. Thus, many results are purely experimental and lack a generality which can only be achieved from theoretical considerations. The target system described is a DS-SS communications system operating environment which consists of additive white Gaussian noise and continuous wave interference. The interceptor uses a radiometer in conjunction with interference excision techniques to detect the presence of the target signal. It is shown that much of the interceptor's effectiveness is restored by the interference excision.<>