美研制超级“量子雷达” 隐身战机显原形

这是对付转发干扰的

中国目前还没正式展开相关研究吗?
不管偷抢，先把美国的技术拿过来

这是对付转发干扰的
只发现一只鸟和没有发现一架飞机没区别……

hecz 发表于 2015-4-26 18:57
只发现一只鸟和没有发现一架飞机没区别……
转发干扰装置可以让一大堆的无人机看起来像是战斗机

反干扰不等于反隐。讨厌标题党。

转发干扰装置可以让一大堆的无人机看起来像是战斗机

没有这种转发装置吧？想判断飞机型号，飞机外形和回波强度和距离还有飞行姿态是非常重要的参考体系，如果能用自己的信号覆盖对方信号，不如直接创造假目标了。

看明白了，利益量子特征加密技术新型雷达，

主动扫描敌方时，能防止信号被截获，这样能有效地防止敌方干扰机返送出虚假信号把自己骗了；
被动时，当被敌方雷达扫描时，能利用量子特性，把信号重组，送给敌方虚假信号，欺骗敌方。能做到现时干扰机的电子隐身效果。

hecz 发表于 2015-4-26 19:21
没有这种转发装置吧？想判断飞机型号，飞机外形和回波强度和距离还有飞行姿态是非常重要的参考体系，如 ...
http://v.youku.com/v_show/id_XNjcwNTY1MjA0.html?from=s1.8-1-1.2


http://lt.cjdby.net/thread-1165188-1-1.html

F-35还可利用其采用数字射频存储(DRFM)技术的电子战系统来欺骗敌方防空系统，使后者得到虚假的RCS、距离、速度和角度信息，从而提高飞机的生存能力

这些都是可以做到的，比如传统干扰，有速度门，距离门，回波堵塞干扰等等。转发式干扰只是其中一个组成部分，针对同样技术标准的对手，做不到改变自己的回波特征变成另一架飞机。
一般来说，转发式干扰已经不先进了。旁瓣对消和脉内变频脉间跳频都可以很好的应付转发式干扰。

笑脸男人 发表于 2015-4-26 19:32
http://v.youku.com/v_show/id_XNjcwNTY1MjA0.html?from=s1.8-1-1.2

这些都是可以做到的，比如传统干扰，有速度门，距离门，回波堵塞干扰等等。转发式干扰只是其中一个组成部分，针对同样技术标准的对手，做不到改变自己的回波特征变成另一架飞机。
一般来说，转发式干扰已经不先进了。旁瓣对消和脉内变频脉间跳频都可以很好的应付转发式干扰。

雷达做目标识别的选择是敌我识别器（IFF）或非合作目标识别（NTCR）. NTCR的两种方式喷气发动机周期调制 JEM(Jet Engine Modulation)或者HRR成像。

隐身飞机通常会采用S型的进气道或者雷达屏蔽器遮蔽雷达对发动机叶片的探测

而对于HRR成像，传统的转发干扰设备无法有效干扰的

这就需要以数字射频存储器（Digital Radiofrequency Memory,DRFM）作为硬件基础的波形篡改/转发干扰（waveform doctoring measure）措施.DRFM可以将接受的数量巨大的雷达脉冲信号从模拟信号转化为不会随着时间而磨损的数字信号,一次为基础，计算机才能进行高速分析和调制.而波形篡改则是通过分析雷达信号在机体的特征明显的边缘,倾角和周边海域的反射信号,复制和调制虚假的回波信号以欺骗雷达.

而对付跳频也需要能收集到足够多的信号特征，才能进行分析，找到某种规律以进行反制，所以DRFM这类硬件一个重要的技术标准就是对信号的存储能力

hecz 发表于 2015-4-26 19:39
这些都是可以做到的，比如传统干扰，有速度门，距离门，回波堵塞干扰等等。转发式干扰只是其中一个组成 ...

雷达做目标识别的选择是敌我识别器（IFF）或非合作目标识别（NTCR）. NTCR的两种方式喷气发动机周期调制 JEM(Jet Engine Modulation)或者HRR成像。

隐身飞机通常会采用S型的进气道或者雷达屏蔽器遮蔽雷达对发动机叶片的探测

而对于HRR成像，传统的转发干扰设备无法有效干扰的

这就需要以数字射频存储器（Digital Radiofrequency Memory,DRFM）作为硬件基础的波形篡改/转发干扰（waveform doctoring measure）措施.DRFM可以将接受的数量巨大的雷达脉冲信号从模拟信号转化为不会随着时间而磨损的数字信号,一次为基础，计算机才能进行高速分析和调制.而波形篡改则是通过分析雷达信号在机体的特征明显的边缘,倾角和周边海域的反射信号,复制和调制虚假的回波信号以欺骗雷达.

而对付跳频也需要能收集到足够多的信号特征，才能进行分析，找到某种规律以进行反制，所以DRFM这类硬件一个重要的技术标准就是对信号的存储能力

雷达做目标识别的选择是敌我识别器（IFF）或非合作目标识别（NTCR）. NTCR的两种方式喷气发动机周期调制  ...
脉内变频和脉间跳频是根据时间和频谱分布区分真假信号。旁瓣对消的原理是根据接收的旁瓣能量区分真假信号。
很显然都可以良好的对抗转发式干扰。

hecz 发表于 2015-4-26 20:19
脉内变频和脉间跳频是根据时间和频谱分布区分真假信号。旁瓣对消的原理是根据接收的旁瓣能量区分真假信号 ...
http://www.doc88.com/p-9085745959640.html

这种东西50年之后再说吧

这个东西就是一个信号特征的储存器，需要的时候调出信号特征，依赖于平时采集大量信号。可以适用于大部分干扰措施。想仅仅靠这个压制住现代抗干扰设计，显然还是不够。

笑脸男人 发表于 2015-4-26 20:29
http://www.doc88.com/p-9085745959640.html

这个东西就是一个信号特征的储存器，需要的时候调出信号特征，依赖于平时采集大量信号。可以适用于大部分干扰措施。想仅仅靠这个压制住现代抗干扰设计，显然还是不够。

hecz 发表于 2015-4-26 20:42
这个东西就是一个信号特征的储存器，需要的时候调出信号特征，依赖于平时采集大量信号。可以适用于大部 ...
所以MD需要平时大量采集目标信号

还要发展隐身无人机去做目标信号收集

原始文献是15年2月份发表在PRL上的一篇文章：S. Barzanjeh et al., Phys. Rev. Lett. (2015)。下面是PRL编辑的一个评论文章，懂鸟语的CDer可以看看。
“量子雷达”的主要目的是将目标信号从环境噪声中凸显出来，以达到探测隐身目标的目的。
当然，现在还只是原理性研究，距离实用还有很长距离，这应该是"DARPA"这种机构的研究项目。

Focus: Quantum Mechanics Could Improve Radar
Published February 27, 2015  |  Physics 8, 18 (2015)  |  DOI: 10.1103/Physics.8.18

A proposed device would extend a quantum entanglement scheme previously demonstrated for visible photons into the microwave regime, where it could boost radar performance.
Microwave Quantum Illumination

Shabir Barzanjeh, Saikat Guha, Christian Weedbrook, David Vitali, Jeffrey H. Shapiro, and Stefano Pirandola
Phys. Rev. Lett. 114, 080503 (2015)
Published February 27, 2015
+Enlarge image Figure 1
S. Barzanjeh et al., Phys. Rev. Lett. (2015)

Seeing the unseen. A quantum radar device could detect microwave reflections that would normally be swamped by the noisy background radiation. It would contain two devices capable of interconverting visible light with microwaves, a capability that exists with current technology. First the top converter couples two entangled beams, a microwave one (red wavy line) and a visible one (red straight line); then the microwave reflection is converted to visible light that interferes with the initial visible beam in the detector.

Quantum-mechanical effects can be exploited to enhance the sensitivity of microwave technologies such as radar, according to new calculations. The authors describe a scheme that would extend the notion of “quantum illumination”—which aids the sensing of weakly reflective targets in a noisy background—from visible wavelengths to microwaves, where its benefits should be more significant. If extended further to radio frequencies, the method could increase the sensitivity of magnetic-resonance imaging.

Quantum illumination was first outlined seven years ago by Seth Lloyd and co-workers of the Massachusetts Institute of Technology [1, 2]. A light beam is split into two beams that are quantum-mechanically entangled, meaning that the quantum states of the photons in each beam are strongly correlated. When two correlated beams interfere in a detector, the signal is amplified compared with uncorrelated beams. In quantum illumination, one of the two beams (the idler) goes straight to a detector, but the other (the probe) is sent out to sense a target. If the target is present, an echo is reflected from it and travels back to the detector, where it interferes with the idler beam. Even if the entanglement between the two beams is broken up by noise in the environment, some residual correlations remain that affect the interference, so that probe photons can be distinguished from background photons. This makes it possible to identify reflections from the target even when this echo is very weak.

Quantum illumination was demonstrated experimentally in 2013 for visible wavelengths [3], but Stefano Pirandola of the University of York in the UK and coworkers say that at longer wavelengths quantum illumination is both harder to achieve and potentially more useful. They describe a scheme for conducting the experiment at microwave (radar) frequencies and predict its effectiveness with currently available technology.

For “stealth” objects like aircraft and boats developed by the military, radar reflections are reduced by special surface coatings and may be swamped by the ambient thermal background. But if the probe signal contained photons “labeled” by quantum illumination, a faint radar echo would still stand out.

At the core of the proposed method is a means of interconverting microwave and optical signals using a so-called electro-optomechanical converter [4, 5]. This device would consist of optical and microwave cavities for storing each kind of radiation, with a nanoscale vibrating object (such as a piezoelectric crystal or a metallic membrane) serving as the connection between the two. The oscillator can couple electromagnetic vibrations in the two cavities, despite their different frequencies.

In the first step of their proposed experiment, a converter entangles the radiation in the two cavities, and the microwaves are then released as the probe beam, while the visible photons become the idler beam. If the probe bounces off the target and returns to the device, a second electro-optomechanical converter converts it to a visible-light beam, which is then allowed to interfere with the idler in a detector. The researchers call their scheme “quantum radar.”

“Our work supports the use of quantum correlations as a general resource for quantum sensing in a very noisy background, like that in the microwave regime,” says Pirandola. In principle the method could work with such weak sensor beams that it would be totally “noninvasive”—for example, a military aircraft wouldn’t register that it had been probed.

Applied physicist Michael Devoret of Yale University calls the work “very interesting and valuable,” adding that “the basic ideas behind this kind of scheme are exciting intellectually.” But whether the proposed method will work remains to be seen. ”I’m not sure it could be applied to real radar, because the photon absorption in air might scramble everything,” says Devoret. Constructing a working device “is challenging and will require some time,” Pirandola acknowledges.

But the researchers say that it might also be possible to extend the idea to radio frequencies. That would open up new opportunities for non-invasive detection, for example using magnetic-resonance methods such as NMR and MRI for looking at delicate biological samples where absorption of radiation must be minimized.

This research is published in Physical Review Letters.

–Philip Ball

Philip Ball is a freelance science writer in London and author of Curiosity: How Science Became Interested in Everything (2012).


References

    S. Lloyd, “Enhanced Sensitivity of Photodetection via Quantum Illumination,” Science 321, 1463 (2008).
    S.-H. Tan, B. I. Erkmen, V. Giovannetti, S. Guha, S. Lloyd, L. Maccone, S. Pirandola, and J. H. Shapiro, “Quantum Illumination with Gaussian States,” Phys. Rev. Lett. 101, 253601 (2008).
    Z. Zhang, M. Tengner, T. Zhong, F. N. C. Wong, and J. H. Shapiro, “Entanglement’s Benefit Survives an Entanglement-Breaking Channel,” Phys. Rev. Lett. 111, 010501 (2013).
    J. Bochmann, A. Vainsencher, D. D. Awschalom, and A. N. Cleland, “Nanomechanical Coupling between Microwave and Optical Photons,” Nature Phys. 9, 712 (2013).
    R. W. Andrews, R. W. Peterson, T. P. Purdy, K. Cicak, R. W. Simmonds, C. A. Regal, and K. W. Lehnert, “Bidirectional and Efficient Conversion between Microwave and Optical Light,” Nature Phys. 10, 321 (2014).


原始文献是15年2月份发表在PRL上的一篇文章：S. Barzanjeh et al., Phys. Rev. Lett. (2015)。下面是PRL编辑的一个评论文章，懂鸟语的CDer可以看看。
“量子雷达”的主要目的是将目标信号从环境噪声中凸显出来，以达到探测隐身目标的目的。
当然，现在还只是原理性研究，距离实用还有很长距离，这应该是"DARPA"这种机构的研究项目。

Focus: Quantum Mechanics Could Improve Radar
Published February 27, 2015  |  Physics 8, 18 (2015)  |  DOI: 10.1103/Physics.8.18

A proposed device would extend a quantum entanglement scheme previously demonstrated for visible photons into the microwave regime, where it could boost radar performance.
Microwave Quantum Illumination

Shabir Barzanjeh, Saikat Guha, Christian Weedbrook, David Vitali, Jeffrey H. Shapiro, and Stefano Pirandola
Phys. Rev. Lett. 114, 080503 (2015)
Published February 27, 2015
+Enlarge image Figure 1
S. Barzanjeh et al., Phys. Rev. Lett. (2015)

Seeing the unseen. A quantum radar device could detect microwave reflections that would normally be swamped by the noisy background radiation. It would contain two devices capable of interconverting visible light with microwaves, a capability that exists with current technology. First the top converter couples two entangled beams, a microwave one (red wavy line) and a visible one (red straight line); then the microwave reflection is converted to visible light that interferes with the initial visible beam in the detector.

Quantum-mechanical effects can be exploited to enhance the sensitivity of microwave technologies such as radar, according to new calculations. The authors describe a scheme that would extend the notion of “quantum illumination”—which aids the sensing of weakly reflective targets in a noisy background—from visible wavelengths to microwaves, where its benefits should be more significant. If extended further to radio frequencies, the method could increase the sensitivity of magnetic-resonance imaging.

Quantum illumination was first outlined seven years ago by Seth Lloyd and co-workers of the Massachusetts Institute of Technology [1, 2]. A light beam is split into two beams that are quantum-mechanically entangled, meaning that the quantum states of the photons in each beam are strongly correlated. When two correlated beams interfere in a detector, the signal is amplified compared with uncorrelated beams. In quantum illumination, one of the two beams (the idler) goes straight to a detector, but the other (the probe) is sent out to sense a target. If the target is present, an echo is reflected from it and travels back to the detector, where it interferes with the idler beam. Even if the entanglement between the two beams is broken up by noise in the environment, some residual correlations remain that affect the interference, so that probe photons can be distinguished from background photons. This makes it possible to identify reflections from the target even when this echo is very weak.

Quantum illumination was demonstrated experimentally in 2013 for visible wavelengths [3], but Stefano Pirandola of the University of York in the UK and coworkers say that at longer wavelengths quantum illumination is both harder to achieve and potentially more useful. They describe a scheme for conducting the experiment at microwave (radar) frequencies and predict its effectiveness with currently available technology.

For “stealth” objects like aircraft and boats developed by the military, radar reflections are reduced by special surface coatings and may be swamped by the ambient thermal background. But if the probe signal contained photons “labeled” by quantum illumination, a faint radar echo would still stand out.

At the core of the proposed method is a means of interconverting microwave and optical signals using a so-called electro-optomechanical converter [4, 5]. This device would consist of optical and microwave cavities for storing each kind of radiation, with a nanoscale vibrating object (such as a piezoelectric crystal or a metallic membrane) serving as the connection between the two. The oscillator can couple electromagnetic vibrations in the two cavities, despite their different frequencies.

In the first step of their proposed experiment, a converter entangles the radiation in the two cavities, and the microwaves are then released as the probe beam, while the visible photons become the idler beam. If the probe bounces off the target and returns to the device, a second electro-optomechanical converter converts it to a visible-light beam, which is then allowed to interfere with the idler in a detector. The researchers call their scheme “quantum radar.”

“Our work supports the use of quantum correlations as a general resource for quantum sensing in a very noisy background, like that in the microwave regime,” says Pirandola. In principle the method could work with such weak sensor beams that it would be totally “noninvasive”—for example, a military aircraft wouldn’t register that it had been probed.

Applied physicist Michael Devoret of Yale University calls the work “very interesting and valuable,” adding that “the basic ideas behind this kind of scheme are exciting intellectually.” But whether the proposed method will work remains to be seen. ”I’m not sure it could be applied to real radar, because the photon absorption in air might scramble everything,” says Devoret. Constructing a working device “is challenging and will require some time,” Pirandola acknowledges.

But the researchers say that it might also be possible to extend the idea to radio frequencies. That would open up new opportunities for non-invasive detection, for example using magnetic-resonance methods such as NMR and MRI for looking at delicate biological samples where absorption of radiation must be minimized.

This research is published in Physical Review Letters.

–Philip Ball

Philip Ball is a freelance science writer in London and author of Curiosity: How Science Became Interested in Everything (2012).


References

    S. Lloyd, “Enhanced Sensitivity of Photodetection via Quantum Illumination,” Science 321, 1463 (2008).
    S.-H. Tan, B. I. Erkmen, V. Giovannetti, S. Guha, S. Lloyd, L. Maccone, S. Pirandola, and J. H. Shapiro, “Quantum Illumination with Gaussian States,” Phys. Rev. Lett. 101, 253601 (2008).
    Z. Zhang, M. Tengner, T. Zhong, F. N. C. Wong, and J. H. Shapiro, “Entanglement’s Benefit Survives an Entanglement-Breaking Channel,” Phys. Rev. Lett. 111, 010501 (2013).
    J. Bochmann, A. Vainsencher, D. D. Awschalom, and A. N. Cleland, “Nanomechanical Coupling between Microwave and Optical Photons,” Nature Phys. 9, 712 (2013).
    R. W. Andrews, R. W. Peterson, T. P. Purdy, K. Cicak, R. W. Simmonds, C. A. Regal, and K. W. Lehnert, “Bidirectional and Efficient Conversion between Microwave and Optical Light,” Nature Phys. 10, 321 (2014).