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本文研究了通信数据链系统的微弱小信号增强与接收检测算法。为了提升通信数据链系统中信号的接收性能,在低信噪比条件下,提出基于非线性系统的小信号检测算法。在非线性系统中,适当强度的噪声在一定程度上会增强输出信号的幅值,从而实现在强大的噪声背景环境下对微弱小信号的增强和检测功能。本文着重研究了非线性系统中的双稳态系统,分析了通信数据链系统中的 MSK 信号输入到双稳态系统中,利用 Matlab 仿真出输入非线性系统前后的信号时域频域波形图,进而分析了基于通信数据链系统的小信号增强与检测算法性能。Matlab 仿真结果表明,本文提出的算法可以有效改善低信噪比条件下的通信信号接收性能,在信号处理与接收领域有着重大的应用前景。 相似文献
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雷达通信一体化是指在实现二者硬件共用的基础上,进一步进行波形融合,即用一个信号同时执行雷达和通信功能的技术,以优化系统性能,节约频谱资源。阐述了一体化的技术内涵及发展阶段,分析了线性调频(LFM)信号在一体化系统中的应用潜力,总结了LFM一体化波形设计、高频宽带LFM信号以及LFM一体化波形光学产生和处理的研究进展。分析认为,微波光子将在雷达通信一体化系统中发挥重要作用,未来的雷达通信一体化系统不仅是光学和电学技术相融合的系统,也是模拟和数字技术相结合的系统。 相似文献
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通信侦察系统具有实时性要求,目前都采用宽开通信侦察系统,它可以大大提高搜索速度,提高信号的截获概率,但如何快速有效地分离出同时截获的多信号是一个急待解决的难题。文章提出一种基于盲分离技术的宽开通信侦察系统,具有良好的应用前景。 相似文献
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对综合电子战系统来说,最为重要的就是那些与武器系统有关的信号。这里面包括:雷达和数据传输装置信号以及通信信号。总的米说,雷达和数据传输装置信号比通信信号的威胁更大。因此,雷达数据是综合电子战系统的首选目标。同时,在指挥控制对抗中对通信网进行电子攻击也是必然的。军事通信干扰的主要目的是通过限制备军事系统之间的信息交流系统将指挥员与部队分离,限制其对形势的了解。对通信系统实施电子攻击可以破坏敌通信或向数据网传递假的或欺骗性的信息。最理想的破坏就是破坏通信网的枢纽。 相似文献
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宽开通信侦察中多信号盲分离应用研究 总被引:1,自引:0,他引:1
宽开通信侦察系统可以大大提高搜索速度,提高信号的截获概率,但如何快速有效地分离出同时截获的多信号是一个急待解决的难题,盲分离技术为多信号分离提供了一种新的思路,实验结果表明盲分离技术在宽开通信侦察中的有效性,并显示出它在通信侦察中的广阔前景。 相似文献
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随着光纤通信系统应用规模的扩大,信号传输工作中的损伤问题也越来越严重。文章首先对通信系统中的信号损伤及补偿进行了阐述,结合案例,对高速光线通信系统中信号损伤补偿技术进行了详细分析,旨在强化信号补偿技术,解决信号损伤问题,确保通信系统平稳运行。 相似文献
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The performance of a hybrid slow frequency hopped direct sequence multiple frequency shift keyed (SFH/DS MFSK) communication link in the presence of partial band multitone jamming is considered. The communication signal is characterized by a DS-spread MFSK signal bandwidth that may exceed the FH slot spacing, and the signal consists of multiple M-ary symbols per DS code period. An equation for the bit error rate (BER) is developed for the signal in the presence of multitone jamming. The equation is flexible enough to allow examination of optimization of jamming strategy. It is shown that the jamming strategy may be optimized by varying the number of tones, their placement, or both. It is shown that in the presence of optimized jamming, overlapping systems are more resistant to jamming than nonoverlapping systems with equal parameters (except for the number of FH slots). It is also demonstrated that, in some cases, the addition of DS spreading to an FH system, without increasing the total system bandwidth, can significantly improve the system's resistance to partial band multitone jamming 相似文献
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GSM网络作为无线智能监控系统的信息传输平台是一种很有效的方法,本文介绍了一个基于单片机、GSM网络收发技术和热释电红外传感器的红外报警器,这个对人们的住宅安全防护智能化的发展,满足人们对居住安全的强烈要求方面有一定的实际意义。本设计利用STC89C52单片机为控制器,SIM300作为无线通信模块,红外传感器作为监控单元,单片机和SIM300通过串口进行通讯。如果监控单元探测到有人闯入,作为信号产生的红外探测器发出一个信号,初始的热释电红外传感器信号经过滤波技术消除噪声从而平滑和变为一个方波信号,通过这个方波信号的作用,STC89C52能够控制SIM300模块发送短消息给用户报警。 相似文献
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MIMO无线传输技术是通信领域的一项重要技术突破,它能在不增加带宽与功率的情况下成倍地提高无线通信系统的容量和频谱效率,是新一代无线通信系统中的关键技术之一。本文探讨了MIMO系统中常用的几种空时处理的关键技术,主要包括MIMO信道建模、波束赋形、空时编码、空间复用等,及其这些技术所面临的问题以及进一步的发展方向。 相似文献
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聚焦北京地铁交通轨道应急抢险可视化通信与信号传输的应用领域,针对传统的有线通信系统存在的传输距离短、线路铺设灵活性差;无线通信系统中,无线自组网技术存在的收发单元间传输能力与适应性差;卫星与公网结合的通信系统存在的信号源不稳定等缺陷。提出了WIFI多级桥接应急多媒体通信系统架构,研究基于5.8GHz的WIFI多级接桥技术并研制相关设备,在无线自组网技术基础上,在传输能力与适应性方面进行了改进,能够有效适应远距离、遮挡及垂直差异存在的信号传输场景。提出采用广泛应用的公网4G信号构建通信系统,有效避免当车载基站作为信号源造成的不稳定性,当应急救援现场无4G信号覆盖时,结合WIFI多级桥接技术提供的网络传输保障功能,从而使得整体桥接与通信系统可满足所有的地铁抢险环境并实现相应功能要求。 相似文献
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B. J. Mayr ÖVE IEEE H. Weinrichter ÖVE IEEE 《e & i Elektrotechnik und Informationstechnik》1997,114(3):123-130
Modern communication systems offer high speed and reliable data transmission services. The quality of these services is achieved by combining coded multi-level modulation techniques and modern digital signal processing (Viterbi-decoding) in the receiver. In this paper we first present an introduction to Trellis Coded Modulation (TCM) and then some new results on unversal techniques adapted for the AWGN-channel as well as for the fading channel. It is shown that TCM is well suited for communication channels with time variant characteristics (e.g. mobile communication channels), especially when our new codes are applied. 相似文献
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It is determined the throughput of multi-channel communication systems, where at each channel optimal linear predistortion and signals filtering are applied. It is compared the efficiency of such systems in case of different correlation degree in transmitted signal. 相似文献
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This article introduces a composable component model that can be used for performance analysis of complex digital signal processing (DSP) systems consisting of several computation resources communicating via some shared media. It reviews different methods of analyzing the performance of such communication-centric systems, including simulation, trace-based simulation, and symbolic methods. Finally, a component model that can be used to formally state the relationship between the usage and the processing capabilities of different computation and communication resources is established. 相似文献
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We present a tutorial review of adaptive signal processing applied to a digital communication receiver operating in a nonstationary environment. The topics covered include feedforward and recurrent neural networks and their applications to communication systems. The article also includes a discussion of turbo decoding, which involves a form of recurrent learning. It concludes with a discussion of the various aspects of adaptive signal processing as they relate to digital communication receivers. 相似文献
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《Signal processing》2007,87(2):337-351
In some antenna array-based wireless communication systems the received signal is multidimensional and can be treated as a tensor (3D array) instead of a matrix (2D array). In this paper, we make use of a generalized tensor decomposition known as constrained Block-PARAFAC and propose a tensor (3D) model for the signal received by three types of wireless communication systems. The considered wireless communication systems are multiuser systems subject to frequency-selective multipath and employing multiple receiver antennas together with (i) oversampling or (ii) direct-sequence spreading or (iii) multicarrier modulation. The proposed modeling approach aims at unifying the received signal model of these systems into a single PARAFAC model. We show that the proposed model has a constrained structure, where model constraints and associated dimensions depend on each particular system. The proposed constrained Block-PARAFAC model is demonstrated by expanding the tensor using Kronecker products of canonical vectors. As an application of this model to tensor signal processing, a new tensor-based receiver is proposed for blind multiuser equalization, which combines PARAFAC-based modeling with a subspace method. Simulation results are presented to illustrate the performance of the proposed blind receiver. 相似文献