共查询到19条相似文献,搜索用时 93 毫秒
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雷达接收机数字化分析 总被引:1,自引:0,他引:1
通过实践证明,雷达数字接收机与模拟接收机相比,无论从电路结构还是从性能上,都充分体现了其优越性。在介绍某种雷达中频数字接收机的基础上,重点阐述了直接数字频率合成技术、直接中频采样和数字下变频技术,并给出了这2种数字技术的实现方法。介绍了直接数字频率合成芯片AD9854,并根据易于宽带滤波器设计的原则,推导了给定参数下使低通滤波器过渡带最宽的最佳采样频率。 相似文献
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常规体制单脉冲火控跟踪雷达面临着相控阵体制雷达的严峻挑战。介绍了中频数字化技术、数字脉冲压缩技术在火控雷达接收机中的应用,阐述了低功率发射机、宽带雷达接收系统的性能优势,提出了新的雷达成像技术在火控雷达中的应用,对火控雷达的发展趋势进行了展望。 相似文献
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简要介绍了基于变频技术的软件无线电结构的形成,宽带中频采样接收机的变频原理及其过程,并以超外差接收技术和软件无线电理论为基础,从变频技术的视角分析了宽带中频带通采样接收结构的频率变换及频谱搬移过程,并给出了一种基于变频技术的软件无线电宽带中频采样接收机的硬件实现方案。 相似文献
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基于AD6644设计了一个中频采样模块,分别用于一种脉冲编码调制/调频遥测数字接收机和一种宽带雷达数字接收机中,实验结果证明两种数字接收机均能正确地解调信号,达到了预定指标。 相似文献
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In electronic-warfare (EW) receiver applications, real-time measurement of the radar signals' carrier frequencies is mandatory and considered to be one of the most important radar parameters. Accurate frequency detection can be used to sort and deinterleave signals in a dense signal environment where multiple signals arrive simultaneously presenting severe problems unless they can be differentiated appropriately. Researchers and engineers are actively looking for new algorithms for high resolution wideband receivers with easier implementation. This paper presents an adaptive gain control and dynamic thresholding wideband digital receiver to accurately detect two simultaneous high dynamic range signals, even when their signal frequencies are very close. The proposed fast Fourier transform (FFT) based receiver examines incoming signal characteristics and provides real-time accomplishment of these tasks, by way of using an adaptive gain-control amplifier, a squarer, two analog-to-digital converters, and two FFT's. The wideband receiver offers high probability of intercept over wide instantaneous RF bandwidths, high dynamic ranges and sensitivity. Two simultaneous signal accommodations and their characteristics are provided to demonstrate the improvements over presently used receivers in this field. 相似文献
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随着现代科学技术的迅猛发展及应用市场的迫切需求,现代雷达也出现了走向多功能综合一体化方向的趋势,用户希望在一部雷达上就能综合各种不同的功能,完成各种不同的任务,这就需要多波段工作的、可重构的雷达系统及多波段可重构雷达接收机。文中对各种不同的多波段接收机技术进行了分析,提出了一种新的多波段可重构雷达接收机结构,它不仅结构简单,可以全集成化,同时又能获得较好的性能。 相似文献
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Adiseno Mohammed Ismail Håkan Olsson 《Analog Integrated Circuits and Signal Processing》2002,30(1):59-67
In this paper, a modified front-end receiver configuration, which consists of an LNA and mixer suitable for zero-IF or low-IF receivers, is presented. The idea is to achieve a better linearity for receivers by combining circuit and system level solutions. Three circuit topologies, two in bipolar and one in CMOS technology, are presented in this paper with their simulation results. One of the bipolar topologies has been implemented and measurement results are presented. An IIP3 of up to +0.6 dBm of a combined bipolar LNA and mixer is achieved, depending on frequency of interest and with an acceptable noise figure performance at a current consumption of less than 13 mA from 5 V supply voltage in one circuit and 3 V supply voltage in the other one. An IIP3 up to +5 dBm is achieved for the CMOS topology at a lower overall gain and acceptable noise figure (14.4 mA and 3 V). All circuits presented in this paper are wideband circuits, suitable for area-efficient multiband receivers. 相似文献
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交叉采样是提升雷达接收机采样率的有效方法,但该方法会引入通道失配,通道失配将严重降低系统的性能。本文首先介绍基于OpenVPX平台的四通道交叉采样宽带雷达接收机的硬件设计;其次对采集系统通道失配误差及其估计方法进行分析;最后针对传统的通道失配校正方法耗费大量时间的问题,提出一种在线校正系统通道失配的方法,该方法提高了通道失配校正的效率。测试结果表明,该设计可实现以采样率9.6Gsps、精度10bit对频带为1GHz~4GHz的中频信号直接采集,能够满足宽带雷达接收机脉冲压缩处理的要求,已成功应用于某宽带雷达。 相似文献