共查询到19条相似文献,搜索用时 328 毫秒
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分析了参考信号耦合有用信号时,实际自适应干扰对消系统的时域特性。分析表明,参考信号含有用信号导致系统时变,改变系统的最佳权值,使系统的干扰对消效果下降,并对有用信号的接收产生影响。根据实际共平台通信系统的收发耦合特性,从时域角度分析得到系统干扰对消比和有用对消比的计算表达式,并得到干扰对消比和有用对消比随相对时延相位变化的规律。提出一种时延匹配方法,通过匹配参考信号提取点至正交功分器输出与接收天线至合成信号注入点间的时延,可以有效抑制参考信号耦合有用信号导致干扰对消效果下降的问题。仿真结果表明,所提出的时延匹配方法能消除有用信号对干扰对消比的影响,还能提高干扰对消效果。 相似文献
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收发隔离度一直是电子战系统的关键技术,若隔离度不够,发射的干扰信号会耦合到侦察接收机,使接收机不能正常工作甚至产生自激.分析了传统收发隔离改善技术和自适应干扰对消技术的优缺点,提出了基于系统辨识的干扰对消方法,利用耦合通路的线性非时变性,拟合出干扰耦合通路的传递函数.仿真和实验结果表明,该方法能有效对消各种干扰信号,同时不会影响接收的雷达信号,能够满足系统隔离度的要求. 相似文献
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宽带泄漏信号自适应对消器的性能 总被引:1,自引:0,他引:1
自适应对消器可以有效地消除雷达发射机宽带泄漏信号对雷达系统本身的影响。本文依据环路模型建立了描述自适应对消器工作过程的随机微分方程,求得了随机微分方程的瞬态解及其统计特性。最后导出了衡量对消器性能的干扰对消比的理论公式。 相似文献
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相关干扰对旁瓣对消系统性能的影响 总被引:1,自引:0,他引:1
分析了相关干扰对旁瓣对消系统性能的影响,推导出了相关干扰下的单辅助通道的旁瓣对消系统的对消比的表达式.分析表明:相关干扰可以使旁瓣对消系统的性能退化,其退化的程度正比于相关干扰的功率和目标信号的功率.最后通过计算机仿真验证了理论分析的正确性. 相似文献
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针对宽带相控阵雷达中的关键技术如子阵划分、数字波束形成以及宽带自适应干扰对消等展开研究,给出了宽带阵列划分的准则和方法并以线性调频信号为例提出了一种数字波束形成方法和宽带自适应干扰对消算法。该方法应用数字时变相位补偿方法代替传统的时间延时单元形成主波束,降低了系统的复杂度并提高了波束形成的性能。基于拉伸处理的宽带自适应干扰对消算法对宽带旁瓣干扰和主瓣干扰都有较好的抑制作用,在强的宽带干扰下仍然可以很好地对目标进行高分辨成像。 相似文献
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The interference cancellation performance of actual co-site antenna interference cancellation system (CICS) under amplitude modulation jamming signal was analyzed.The expressions of the steady-state weights and theirs structure characteristics of the interference cancellation system under the AM signal were given.The formulae of the interference cancellation ratio (ICR) for carrier frequency and side frequency were derived.The influence factors and the influence rules of the ICR were analyzed.The steady state weights of the interference cancellation system (ICS) were the weighting of the carrier frequency optimal weights and the edge frequency optimal weights according to the power ratio.The increase of the signal bandwidth will increase the discreteness of the carrier frequency optimal weights and the edge frequency optimal weights and lead to the decrease of the interference cancellation ratio (ICR).The decrease degree of the edge frequency ICR was greater than that of the carrier frequency ICR.To improve ICR by increasing the gain was limited.The relationship between the interference cancellation ratio limit and the equivalent transmission delay was given.The design method of the interference cancellation system to improve the ICR under the AM signal was proposed.Finally,the correctness and validity of the theoretical analysis was verified by simulation. 相似文献
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依据自适应旁瓣相消原理,着重分析了宽带干扰信号对旁瓣相消性能的影响,针对宽带干扰影响下,主辅天线间的波程差、主辅天线通道频率特性的不一致性以及主天线旁瓣的频率敏感特性等引起的自适应旁瓣相消系统的主辅天线2通道信号的去相关作用,采用了主天线通道均衡和子带自适应相消2种方法改善带宽特性,并通过MATLAB仿真验证,仿真结果表明该两种方法均可明显改善系统的相消性能,达到良好效果。 相似文献
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The digital proportion control is introduced to improve the performance of the analog adaptive interference cancellation system (ICS). For the high frequency parts of the signals after multiplier are not required, the sampling frequency need not satisfy the sampling theorem for high frequency. Because the sampling, calculation and output expend time in digital control, the ideal condition, delay condition and delay-wait condition are taken into account. Through analyzing the system model with three conditions, we gain the stable conditions of the system, the optimization step factors that can make the system converge fastest and the formulas of the interference cancellation ratios (ICRs). One step convergence can be accomplished under ideal condition, whereas the system can not converge in one step under delay condition and delay-wait condition. The calculation results show the convergence speed of delay-wait condition is slower than that of delay condition. The ICR is improved with the increase of the step factor which is in stable bound, but the convergence speed is decreased if the step factor exceeds the optimization step factor. In order to avoid that confine, the method of amending the steady state weight to improve the ICR is proposed. The analyses are in agreement with the computer simulations. 相似文献
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文中介绍了自适应滤波算法的原理和干扰抵消器工作原理,并将LMS算法、NLMS算法和变步长LMS算法分别应用在了干扰抵消器中进行了仿真。仿真的结果表明,三种自适应算法运用到了干扰抵消器中,都可以很好地滤除干扰,提取有用信号。其中运用了变步长LMS算法的干扰抵消器无论在收敛速度和滤波性能上,都要强于其他两种算法。 相似文献
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本文提出一种适用于码分多址系统的低复杂度自适应干扰消除接收机。 在此接收机中,我们首先基于第i个用户的第m个比特的输出引入一组可靠度因子 ,然后根据这组可靠度因子估算出多址干扰,最后通过执行干扰消除可得到符号判决值。通过在加性高斯白噪声信道和多径衰落信道中进行仿真。结果表明,本文提出的这种接收机方案的性能优越于传统检测器和一些已经存在的干扰消除算法,同时保持有较低的算法复杂度。 相似文献