Airborne Doppler Radar

作者:Schetzen, Martin

页数:185

出版时间:2006-6

价格:$ 101.64

isbn号码:9781563478284

具体描述

The author's extensive work in Doppler radar theory - specifically his development of an exact theory for the spectrum of an airborne Doppler radar - is thoroughly presented in this important book. Much of the material presented has not previously appeared in print and anyone involved in Doppler theory and applications, airborne Doppler radar, or aircraft stabilization and navigation will find this book invaluable. Starting with his recognized accomplishments gained while a member of the Apollo 11 lunar landing mission team where he was tasked with determining if radar performance over the Moon might differ from that over the Earth, Schetzen theorized that in guidance and control applications, the actual shape of the Doppler spectrum was not necessary; that only its center frequency and bandwidth were required. Following Apollo, he continued to expand his theory in order to make it more useful - developing equations from which the center frequency and bandwidth could be obtained without first determining the actual Doppler spectrum. As a result of these equations, the author derived his Airborne Doppler Uncertainty Principle which states there is a lower limit of the product of position uncertainty and velocity uncertainty. The book begins with a basic discussion of the Doppler effect and its various applications and how Doppler radar can be used for the stabilization and navigation of aircraft. A quasi-static approximation of the Doppler spectrum is presented along with illustrations and discussion to help the reader gain an intuitive understanding of the approximation and its limitations. A summary of the mathematical concepts required for development of an exact theory is then presented using the case of a narrow beam antenna. This is followed by the development of the exact theory for the general case which is graphically illustrated and compared with the quasi-static approximation. General conditions for which the quasi-static approximation error would be excessive - specifically as applied to laser Doppler radars and low-flying aircraft - are presented. Software, in the form of an executable Matlab[trademark] program which can be used to determine the Doppler spectrum parameters for any antenna pattern and any terrain backscattering, is included. The text develops concepts and theories in a manner that can be readily followed and is supported by graphic illustrations that assist the reader in understanding the theoretical predictions. Where appropriate, examples are presented to illustrate the theory. Final results are summarized for readers who choose not to follow the development of the theory itself.

用户评价

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这本书的叙事节奏堪称一绝，作者在铺陈背景时并没有采用传统的线性叙事，而是巧妙地将时间线进行碎片化处理，如同在空中盘旋的无人机镜头，时而聚焦于某一历史瞬间的微观细节，时而拉升到宏大的时代变迁。我特别欣赏它在描绘人物内心挣扎时的那种克制与精准，没有过多的心理独白，而是通过环境的渲染和人物间微妙的对话张力来展现深层次的情感暗流。比如，书中关于那次至关重要的“决策点”的描写，仅仅用了几页篇幅，却将那种山雨欲来风满楼的紧张感烘托到了极致，那种决策者在巨大压力下保持外表沉静而内心波涛汹涌的对比，读来令人窒息，仿佛我也身处那弥漫着咖啡和焦虑气息的密室之中。更值得称道的是，作者对于意象的运用达到了炉火纯青的地步，那些反复出现的“光影交错”、“金属的冰冷触感”等意象，不仅仅是装饰，它们如同暗语般串联起不同的章节，暗示着主题的深刻内涵——关于透明度与隐藏、关于技术进步对人性的潜在侵蚀。这种文学手法的成熟，让整本书的阅读体验充满了探索的乐趣，每一次重读都能发现新的层次，绝非那种一目了然的畅销书可比拟。

这部作品的结构设计简直是一次对传统叙事边界的大胆挑战，它似乎在探索“非线性时间”在小说中能达到的极限。我印象最深的是作者如何处理不同视角之间的切换，那种转换不是简单的“场景转换”，而更像是在不同的宇宙之间进行维度跃迁。一个场景可能始于微观的粒子碰撞，下一秒就跳跃到了千年之后的历史回响，其间的逻辑联系需要读者主动去构建和填补空白。这种阅读体验极具互动性，仿佛作者提供了一份未完成的蓝图，而读者必须成为那个将碎片重新拼凑起来的“解密者”。这种设计对耐心和专注力提出了极高的要求，我甚至需要时不时地停下来，在脑中绘制一张人物关系和时间轴的图谱才能跟上作者的思路。然而，一旦构建起这个复杂的网络，那种豁然开朗的满足感是无与伦比的。它超越了简单的故事讲述，更像是一场关于信息、记忆和认知的智力游戏，让人不得不惊叹于作者在构思上的宏大与执行上的精细。

我必须赞扬这本书在氛围营造上所达到的那种近乎完美的平衡感。它成功地将两种截然不同的情绪调性融合在了一起：一方面是对未来技术奇观的近乎敬畏的描绘，那些对新科技及其潜力的想象力是如此的瑰丽和富有想象力，让人对人类的创造力产生由衷的赞叹；但另一方面，这种赞叹又被一种持续不断的、低沉的、关于“代价”的忧虑所渗透。书中描写的那些未来场景，虽然视觉效果上光怪陆离，但在情感基调上却异常的压抑和疏离。作者并没有将科技塑造成一个绝对的救世主或者毁灭者，而是将其置于一个模糊的灰色地带，让它成为一把双刃剑，其锋利程度取决于握剑者的意图与能力。这种复杂性和模糊性，让这本书显得格外真实和深刻，它拒绝提供简单的道德裁决，而是将选择的重负交还给了读者，要求我们去思索：在无限的可能性面前，我们究竟愿意牺牲什么来换取进步？

这本书的语言风格，我只能用“冷峻而富于张力”来形容，它毫不留情地撕开了现代社会运行机制下那些光鲜亮丽表象下的粗粝纹理。作者显然对社会学和权力结构有着深刻的洞察，他构建的世界观是如此的精密和无懈可击，以至于让人在阅读过程中不断感到一种被监视、被分析的微妙不安。行文间，充斥着大量精炼、近乎学术论文般的句子，但却被流畅的叙事节奏巧妙地消化了，没有丝毫的晦涩感。特别是描述官僚体系内部运作的那几章，那些冗长但逻辑严密的报告摘录和内部备忘录的穿插，非但没有拖慢节奏，反而像冰冷的注射器一样，将冰冷的现实直接注入读者的血管。我必须承认，初读时需要放慢速度，去细细品味那些看似不起眼的术语和行业黑话，但一旦进入状态，那种被庞大、高效却又缺乏人性的机器所裹挟的宿命感便油然而生。这并非一本提供慰藉的作品，它更像一面镜子，反射出我们这个时代最令人不安的侧面，其价值在于促使读者进行深刻的反思，而不是提供简单的娱乐。