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多频共塔工作模式的使用,为中波发射台节省投资和占地面积提供了便利,但多频共塔模式的使用给信号发射带来一定干扰,影响广播质量。本文对528中波发射台发射功率为100KW的819KHZ和发射功率为50KW的603KHZ多频共塔干扰进行分析,在此基础上,从调配网络设计、陷波网络选择和发射台维护等方面对多频共塔的干扰消除问题展开分析,以便为关注这一话题的人们提供参考。 相似文献
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Dragan Samardzija Narayan Mandayam Ivan Seskar 《The Journal of VLSI Signal Processing》2002,30(1-3):257-271
In this paper we propose a multistage nonlinear blind interference cancellation (MS-NL-BIC) receiver for direct-sequence code-division multiple-access (DS-CDMA) systems. The receiver uses higher order statistics of the received baseband signal. Specifically, we use the second and fourth moments of the received signal to determine a component of the received vector that has significant mean energy and low variability of the energy, both of which are favorable characteristics for application in an interference cancellation scheme that uses hard decisions. The structure of the receiver is multidimensional and can be viewed as a matrix of receivers. Each row in the matrix consists of receivers that perform (hard decisions) cancellation of successive components that have significant mean energy and low variability of the energy. The columns of the matrix essentially resemble multistage receivers that iteratively refine performance from earlier stages. Simulation results show that unlike linear receivers, the MS-NL-BIC is exceptionally efficient in systems with strong and highly correlated interferers, as may be the case in overloaded DS-CDMA systems. 相似文献
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XU Guo-xiong GAN Liang-cai HUANG Tian-xi 《半导体光子学与技术》2005,11(3):154-160
The parallel interference cancellation for multi-carrier DS-CDMA (which is termed FDC-PIC) is proposed by integrating frequency diversity combination. The simulations are made over FDC-PIC with respect to different decision ways hard, soft and linear decisions, respectively, and we conclude that FDC-PIC acquires superior performance improvement over correlation reception of multi-carrier DS CDMA. With an increase in interference cancellation stages, the system performance is improved further. The initial 2 stages bring about the most dominant performance improvement, but up to the 3rd stage the system performance is improved little. It is also shown by the simulation results that FDC-PIC with soft decision would exhibit the best performance with a high implementation complexity, while FDC-PIC with linear decision acquires performance comparable to that of FDC-PIC with soft decision with a reduced-complexity if the number of the interference cancellation stages is the same, which indicates that FDC-PIC with linear decision has optimal performance/complexity tradeoff and therefore will be suitable for practical application in future. 相似文献
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We propose the use of soft feedback estimates for the PIC detector in aDS-CDMA system with FEC. The soft estimates are computed by the a posterioriof the log-MAP decoder. We compare this method with the conventional methodof using tentative hard decisions to perform interference cancellation at eachstage. Simulations under AWGN and multipath asynchronous channels areperformed for comparison. We supply a suitable a posteriori for the log-MAPdecoder, and obtain a suitable soft feedback from the decoder. 相似文献
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基于串行干扰消除的V—BLAST检测 总被引:2,自引:1,他引:2
贝尔实验室分层空时结构(BLAST)是实现多输入多输出(MIMO)无线通信系统空时复用并获得容量增益的一种重要技术.本文将以垂直BLAST(V-BLAST)为主要对象,综述基于串行干扰消除的V-BLAST检测算法及相应的复杂度和误码性能,并对其发展作了有关展望。 相似文献
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为降低TD-SCDMA系统同频组网时同频邻区对终端信道估计造成的同频干扰,提出了一种时域的平行干扰消除算法,相对于串行干扰消除算法,在有多个强同频邻区干扰的条件下,表现出了更好的性能。 相似文献
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无线Ad Hoc网络是一个干扰受限系统,网络的容量取决于网络中的干扰信号功率的大小。在目前针对无线Ad Hoc网络容量进行研究的文献中没有使用有效的抑制干扰信号功率的方法,使得网络容量受到很大限制。提出通过设置保护区域的方法来降低干扰信号强度,重新对无线Ad Hoc网络进行建模,并推导了传输容量的上下界。通过仿真结果可以知道,设置保护区域能够极大程度降低网络中的干扰信号强度,合理地设置保护区域大小能有效提高传输容量。 相似文献
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本文提出了一种适用于多载波直扩码分多址系统(MC-DS-CDMA)上行信道的低复杂度部分并行干扰对消(LC-PPIC)算法.该算法充分利用MC-DS-CDMA系统的信道估计与子载波分集,在各个子载波上将用户分为可靠,普通和无效三类,对可靠用户进行干扰对消处理并消去后,再对普通用户进行相同操作,并放弃无效用户,最后将各个子载波上的结果通过最大比合并(MRC)输出.这样,在降低运算复杂度的同时,更好地抑制了多址干扰(MAI).通过仿真比较,可以看出LC-PPIC算法的误码率(BER)性能明显优于置于载波合并前后的两种部分并行干扰对消(PPIC)算法,特别是在系统负载较重和信噪比较高的情况下,这种优势十分显著. 相似文献
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针对LTE系统小区间干扰不可避免的问题,重点介绍基于交织多址接入(IDMA)的干扰消除,阐述了小区间干扰消除系统模型结构与原理,并给出了LTE系统基于IDMA的干扰消除仿真以及数据分析。 相似文献
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