m****s 发帖数: 18160 | 1 【 以下文字转载自 Boston 讨论区 】
发信人: Sciex (LCMSMS), 信区: Boston
标 题: [供求][Job Opening]: Bioanalytical Scientist
发信站: BBS 未名空间站 (Wed Oct 31 11:18:01 2012, 美东)
My group will have an opening position for Bioanalytical Scientist soon.
This is a mid level position, so we don’t need PhD candidate. Meanwhile, we
only look for local candidate at Great Boston area. If you or someone has
interest, please drop me an email at p***[email protected].
Thanks,
Here is the job description:
Description of duties:
The successfu... 阅读全帖 |
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c******e 发帖数: 355 | 2 这个帖子是接这个帖子“一个新的商业模式”, 见
http://www.mitbbs.com/article_t1/StartUp/31270497_0_1.html
好多人等不及了,我公开这个商业模式吧。这个商业模式的理论基础见哈佛大学教授
Doc Searl的“Intention Economy”。有兴趣的可以去看看这本书。
这个商业模式是这样的:
“marketplace中的任何一件事情,都可以打包成一个叫做“intention”的虚拟产品,
这个虚拟产品首先经过一个叫做”量化“(标准化)的过程,然后在一个类似ebay的网
络竞拍平台上,出售给vendor,vendor出价越低,成越容易成交。
理解这个商业模式的关键是理解“intention”的概念。
intention指一个人想做一件事情的意愿。例如老王想买个电视,张三想找个家教,NSF
想投资一笔钱在一个环保项目,牛津大学想采购一批电脑。。。所有的这些都是
intention。 intention is the urge to spend money on anything.
所以这个商业模式包括两部分:
1. intenti... 阅读全帖 |
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c******e 发帖数: 355 | 3 这个帖子是接这个帖子“一个新的商业模式”, 见
http://www.mitbbs.com/article_t1/StartUp/31270497_0_1.html
好多人等不及了,我公开这个商业模式吧。这个商业模式的理论基础见哈佛大学教授
Doc Searl的“Intention Economy”。有兴趣的可以去看看这本书。
这个商业模式是这样的:
“marketplace中的任何一件事情,都可以打包成一个叫做“intention”的虚拟产品,
这个虚拟产品首先经过一个叫做”量化“(标准化)的过程,然后在一个类似ebay的网
络竞拍平台上,出售给vendor,vendor出价越低,成越容易成交。
理解这个商业模式的关键是理解“intention”的概念。
intention指一个人想做一件事情的意愿。例如老王想买个电视,张三想找个家教,NSF
想投资一笔钱在一个环保项目,牛津大学想采购一批电脑。。。所有的这些都是
intention。 intention is the urge to spend money on anything.
所以这个商业模式包括两部分:
1. intenti... 阅读全帖 |
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f***h 发帖数: 55 | 4 If you are familiar with this field, please let me know (j****[email protected])
Abstract
In this paper, mesoscopic RLC circuit with source is studied with Feynman's
path integral method. Resistance and source in the circuits make the
quantization process rather complicated. To solve the problem, fluctuation
analysis method is proposed to calculate the path integral propagator.
Further more, the wave function and quantum fluctuation of the system are
obtained, and time evolution characters of the syst... 阅读全帖 |
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s*****o 发帖数: 1540 | 5 给我站内发信,告诉我你能审那一篇的编号.要求
1:PHD already or almost obtained in CS or EE。为保证审稿质量,必须是相关专
业的。不可能给其它无关专业博士审理,见谅。
2: Due May 24th
3: let me know your edas id. (If you don't have an edas, I assume you are
not working in these fields).
B1: Concurrency communication, Polygonally Arranged Wireless Data Center,
all Line-of-Sight Links, 60 GHz millimeter-wave, beam-forming, k−pod
fat-tree data center topology mapping to the wireless network, scheduling
algorithm for the wireless network
B2: Data deliver... 阅读全帖 |
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A*****a 发帖数: 485 | 6 不懂电商和网购,看到下面这篇,想起新加坡的bid,好奇。
或许这可以成为本地电商和网购的新思路……
发信人: comehere (come here), 信区: StartUp
标 题: 一个新的商业模式--谜底
发信站: BBS 未名空间站 (Sat Feb 2 18:04:17 2013, 美东)
这个帖子是接这个帖子“一个新的商业模式”, 见
http://www.mitbbs.com/article_t1/StartUp/31270497_0_1.html
好多人等不及了,我公开这个商业模式吧。这个商业模式的理论基础见哈佛大学教授
Doc Searl的“Intention Economy”。有兴趣的可以去看看这本书。
这个商业模式是这样的:
“marketplace中的任何一件事情,都可以打包成一个叫做“intention”的虚拟产品,
这个虚拟产品首先经过一个叫做”量化“(标准化)的过程,然后在一个类似ebay的网
络竞拍平台上,出售给vendor,vendor出价越低,成越容易成交。
理解这个商业模式的关键是理解“intention”的概念。
intention指一个人... 阅读全帖 |
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g*****y 发帖数: 7271 | 7 其实是啃班把一个level,quantize成4份,所以才有所谓的0.75,不是精度到了1%。
haha |
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t******g 发帖数: 17520 | 8 Bryce Seligman DeWitt 是 理论物理学家
He systematically approached the quantization of general relativity, in
particular, developed canonical quantum gravity and manifestly covariant
methods that use the heat kernel. B. DeWitt formulated the Wheeler-deWitt
equation for the wavefunction of the Universe with John Archibald Wheeler
and advanced the formulation of the Hugh Everett's many-worlds
interpretation of quantum mechanics. With his student Larry Smarr he
originated the field of numerical relativity... 阅读全帖 |
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s**********y 发帖数: 8135 | 9 So do you think he believed that the energy of light is quantized?
no
most |
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b*s 发帖数: 82482 | 10 Einstein himself is well known for rejecting some of the claims of quantum
mechanics. While clearly contributing to the field, he did not accept many
of the more "philosophical consequences and interpretations" of quantum
mechanics, such as the lack of deterministic causality. He is famously
quoted as saying, in response to this aspect, "My God does not play with
dice". He also had difficulty with the assertion that a single subatomic
particle can occupy numerous areas of space at one time.
So ... 阅读全帖 |
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a*******u 发帖数: 6324 | 11 嗐!轩哥,那不就是叫做Vibrato嘛。
就抖啊,就震啊,就一个词根啊。
http://en.wikipedia.org/wiki/Vibrato
http://zh.wikipedia.org/wiki/%E9%A1%AB%E9%9F%B3_(%E9%9F%B3%E6%A
颤音 (音乐)
维基百科,自由的百科全书
颤音是一种乐器技巧。
Vibrato
From Wikipedia, the free encyclopedia
Vibrato is a musical effect consisting of a regular, pulsating change of
pitch. It is used to add expression to vocal and instrumental music. Vibrato
is typically characterised in terms of two factors: the amount of pitch
variation ("extent of vibrato") and the speed with which the p... 阅读全帖 |
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m*******n 发帖数: 16 | 13 模拟和数字一直是人们争论的话题,但是并不是像楼主说的那样大多数的人都认为
analog is better. 而正好相反,真正明白其中道理的人都回告诉你digital device
is much better!
数字的好处显而易见,他们可以非常准确的复制,不受任何外界的干扰,唯一影响的因
素就是quantization error,但如果有足够的 bit resolution就不会有问题,CD格式
下信号是16bit, 它的S/N是96dB,音质已经足够高。反观模拟器材,你的模拟信号每通
过一个模拟效果器或者其他模拟器件,就必然会被填加进噪音,噪音大小和你的器件有
关,这种noise是无法避免的。模拟器处理信号时直接deal with voltages,无法保证
准确性,比如说,最简单的例子,一个低通滤波器,在模拟电路中是由一个电阻和一个
电容组成的,电阻值和电容值本身就不精确,而且还受温度影响,所以你就无法保证这
个滤波器的准确程度;而数字滤波器就可以避免这种情况。这只是一个很小的例子,数
字的优越性是模拟所不能比较的。
死活不承认数字比模拟优越的人大都不是真正的audio eng |
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G**Y 发帖数: 33224 | 14 我觉得一个数量级的优化还是可能的。
另外一个paper里,他们大概就是说他们的结果,应该比Shannon, Nyquist啥的还NB,
当然是在特定的假设下。这是摘要:
Conventional approaches to sampling signals or images follow Shannon's
theorem: the sampling rate must be at least twice the maximum frequency
present in the signal (Nyquist rate). In the field of data conversion,
standard analog-to-digital converter (ADC) technology implements the usual
quantized Shannon representation - the signal is uniformly sampled at or
above the Nyquist rate. This article surveys the theo... 阅读全帖 |
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o******1 发帖数: 12177 | 15 this is the fundamental part. as a matter of fact, time is quantized. why ?
because the rabby has a step, and no smaller distanced can be travelled than
a step. the time for the rabby to travel a step is the quantum of time.
therefore, time can not be divided for infinitely small ... |
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H********g 发帖数: 43926 | 16 所以按wikipedia的说法,本生灯不开氧气门的时候会产生很小的碳粒,它的热辐射(
白炽发光)产生黄光。
氧气打开之后,产生的碳粒非常少,剧烈的氧化反应产生大量被激发的自由基(主要是
CH),发射蓝光。
http://en.wikipedia.org/wiki/Flame#Flame_color
In a laboratory under normal gravity conditions and with a closed oxygen
valve, a Bunsen burner burns with yellow flame (also called a safety flame)
at around 1,000 °C (1,800 °F). This is due to incandescence of very fine
soot particles that are produced in the flame. With increasing oxygen supply
, less black body-radiating soot is produced due to... 阅读全帖 |
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z*********e 发帖数: 10149 | 17 不懂,但是感觉很牛
http://tech.sina.com.cn/d/i/2017-07-21/doc-ifyihrit1116695.shtml
撰文 | 吕浩然
7月21日,学术期刊《科学》(Science)在线发表了由美国加利福尼亚大学洛杉矶
分校(UCLA)王康隆课题组主导,斯坦福大学张守晟课题组及上海科技大学寇煦丰课题
组等8家单位合作完成的一项研究成果——研究团队首次在磁性拓扑绝缘体薄膜与超导
体结合的异质结构中发现了一维手性马约拉纳费米子存在的证据[1]。此次工作也是继
去年6月上海交通大学贾金锋课题组发现基态马约拉纳费米子存在的证据之后,该领域
又一重大发现,这让我们距离彻底揭开马约拉纳费米子的神秘面纱又近了一步。
粒子世界有两大家族:费米子家族和玻色子家族,它们分别以物理学家恩利克·费
米(Enrico Fermi,1901—1954)和萨特延德拉·纳特·玻色(Satyendra Nath Bose
,1894—1974)的名字命名。人类已知的所有基本物质粒子都是费米子,是构成物质的
原材料(电子、夸克、中微子),而传递作用力的粒子(光子、介子、胶子、W和Z玻色
子... 阅读全帖 |
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b****s 发帖数: 1300 | 18 这个你正好说反了,Loop到现在还没把黑洞熵掰扯清楚。在90年代中期,Loop的人才还
不少,正因为黑洞熵这个危机,大部分人都撤退了,才成了现在这个局面。
另外,你说100个物理系的不到一个看过dirac的那本哈密顿约束量子化的书?怎么可能
?即使要把规范系统的量子化、brst量子化搞清楚也得从约束系统开始看吧,应该很多人都看过了。除了狄
拉克那本小薄书,老温的书里也讲了约束系统,我还看过一本quantization of gauge systems,里面也花了很大篇
幅讲。 |
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g****t 发帖数: 31659 | 19 LQG那个黑洞熵是因为差个常数?展开科普下?
Dirc那个约束哈密顿的方法我记得有不少人举过反例.从数学方面物理方面都有.
所以后来应该是在量子场论里面非主流了.这点我觉得他说的是对的.
这个你正好说反了,Loop到现在还没把黑洞熵掰扯清楚。在90年代中期,Loop的人才还
不少,正因为黑洞熵这个危机,大部分人都撤退了,才成了现在这个局面。
另外,你说100个物理系的不到一个看过dirac的那本哈密顿约束量子化的书?怎么可能
?即使要把规范系统的量子化、brst量子化搞清楚也得从约束系统开始看吧,应该很多
人都看过了。除了狄
拉克那本小薄书,老温的书里也讲了约束系统,我还看过一本quantization of gauge
systems,里面也花了很大篇
幅讲。 |
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u*******r 发帖数: 143 | 20 其实把科学和信仰放在一起讨论是非常不合适的。
但是关于楼主的问题,随便说一点吧,以下仅从目前我所了解的一点物理知识(可能有
错)出发:
楼主的论点隐含着好几个前提假设:
1. 时间绝对 (时间和物质存在无关,所以可以用时间刻度来衡量所谓“创世”)
2. 时间连续 (时间没有断点,也就是不能所谓的“量子化”)
3. 时间均匀 (时间总是平均地流逝,所以现在的时间尺度可以衡量XX亿年以前,甚至
“创世”)
4. 时间平坦 (时间没有曲率(所以具有单向的时间箭头?))
据我所知,狭义和广义的相对论已经推翻了1,3,4三点,量子理论也提出了quantized
spacetime, 测不准原理提出一个系统的时间与能量之间没有可能精确测量是一个事实,
quantum entanglement 表明时空具有因果性和定域性,......
这些所有的结果,都是从科学角度推翻了我们对于时间本质的经验认识。我相信将来还
有更多的发现能更新我们目前的认识。
楼主,我从没在这个版块发过贴,我挺钦佩您孜孜不倦的斗争精神。
至于我自己,我承认我的智慧太有限,算是个挺愚蠢的人。我只知道凭借我的小脑袋,
我根本搞不清“... 阅读全帖 |
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E*********g 发帖数: 185 | 21 转载。英文链接在最后。
以你对物理学所作的断言来看,你对南传所作的断言对我来讲也没有任何可靠性可言。
既然我不太了解南传,正如你不了解大乘, 我们就不用再讨论下去了。
============================
时间是不是量子化的
时间是不是量子化的?换句话说,时间是不是不连续的可以被分割为一个个基本的单位?
加利福尼亚大学数学学院教授John Baez说:
“回答这个问题很简单:没有人知道!当然,没有一个实验证据表明这样的一个最小的
时间单位的存在,但也没有证据反对这种观点。事实上,我们在构造这样的一个最小时
间单位时没有物理理论的支持,要使他和广义相对论相统一还存在着诸多基本的障碍。
最近的量子引力理论表明,可能存在一种粗略的方法来描述这个问题——但是不是针对
时间的最小单位,而是像对于二维区域的最小面积,三维的最小体积,四位或多维的最
小单位‘超体积’。”
哥伦比亚大学物理天文学院的William G. Unruh给出了这样的回复:
“因为我们没有证据证明时间或者空间是不是量子化的,所以问题就转变成了我们可不
可以找到或者构造一个理论结构来很好的描述时间的这种量子化... 阅读全帖 |
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S**U 发帖数: 7025 | 22 I think it is useful to consider the question this way: are phenomena(both
mental and physical) better modeled as continuous functions, or discrete
functions? If they are better modeled as continuous functions, are there
singularities (hint: is rebirth a singularity?)
For that matter, classical physics model physical variables as continuous
functions. Quantum mechanics model physical variables as discrete functions
(quantized), with continuity as statistical artifacts at macro scale. |
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Y**u 发帖数: 5466 | 23 ☆─────────────────────────────────────☆
insight007 (insight007) 于 (Wed Oct 10 14:07:20 2012, 美东) 提到:
欢迎大家引用杂阿含和相应部讨论 :)
☆─────────────────────────────────────☆
insight007 (insight007) 于 (Wed Oct 10 14:21:15 2012, 美东) 提到:
杂阿含经65:
佛陀指出禅观是如实观察:
”爾時,世尊告諸比丘:
「常當修習方便禪思,內寂其心,所以者何?
比丘!常當修習方便禪思,內寂其心,如實觀察。
云何如實觀察?“
那么如实观察的内容呢?
”此是色,此是色集,此是色滅;此是受……想……行……識,此是識集,此是識滅。
云何色集?受、想、行、識集?“
观察五阴的集与灭为如实观察,不是自己在静坐中自己想象,比如不净观,慈心观之类。
那么什么是五阴的集?
”愚癡無聞凡夫於苦、樂、不苦不樂受不如實觀察此受集,受滅,受味,受患,受離;
不如實觀察故,於受樂著生取,取緣有,有緣生,生緣老、... 阅读全帖 |
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t******g 发帖数: 17520 | 24 就像我说宇宙蛋的时候, 那不是所有particles 都entangled?
但是事实上是吗? 不是, 为啥, 当时超级高温, 没有spacetime,
处于一种超级活跃或者超级不活跃的状态, 没有我们现在的意义上的 纠缠了
所以大胆推测没问题,
意识是可以quantized
multiverse 和轮回联系在一起
我同意上面这句话
但这个问题太大了,究竟怎么理解,物理学还远远没有走到这一步。 |
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y******n 发帖数: 421 | 26 光明日报:张伟平:心中藏着“数学强国梦”编辑:管理员来源:南开大学新闻网时间
:2014-03-30点击:
本报记者 陈建强 通讯员 吴军辉
新闻回放
日前,国际数学顶尖杂志《Acta Mathematica》(《数学学报》)2014年第1期刊登
了南开大学陈省身数学所张伟平院士与法国巴黎第七大学麻小南教授合作的论文。作者
在论文中运用解析局部化的思想和技巧,解决了著名数学家、法国科学院院士Vergne在
2006年国际数学家大会中提出的非紧空间上的几何量子化猜想。
《Acta Mathematica》(《数学学报》)是国际数学领域享有盛誉的顶级数学期刊之
一。由南开大学陈省身数学所张伟平院士与法国巴黎第七大学麻小南教授合作的论文《
Geometric quantization for proper moment maps: the Vergne conjecture》,就
刊登在3月出版的2014年第1期上。
由瑞典科学院Mittag-Leffler数学研究所出版的《Acta Mathematica》致力于刊登
“最高质量的数学论文”,曾刊登过中国数学家苏步青、朱小华的学术论... 阅读全帖 |
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k*********g 发帖数: 791 | 27 暗物质;
是真实存在;
即大规模地结块的以太;
“大规模地结块”的以太,跟通常的物质,仍然有很大的差别;
通常的物质,内部是ordered,structured的,quantized稳定的;
通常的物质,内部蕴藏很多势能;
而“大规模地结块”的以太,只有松散的机构;
无非是一堆非常微小的东西,正好处在同一个物理空间区域;
这些微小的颗粒之间的势能非常弱;
所以她们没有形成singularities;
所以她们没有形成electrodynamic interaction;
所以她们也不emit photons;
而暗能量;
是一种delusion;
是天体物理学家们用错误的广义相对论的一个错误计算结果; |
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s*******f 发帖数: 757 | 29 Can someone help me out on this? I have a executable c program that will
give a sentence like this:
Quantization error of era_adv_jfm/era_tot_adv_high with map era_adv_jfm/high
.map is 860.665649 per sample (632 samples)
What I need is the first numeric value so that I can use it in a schell
script.
Thanks. |
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A******y 发帖数: 2041 | 30 If you cannot see the difference in Western, is it really relevant
biologically? Yes, ELISA, Alpha-scan, and quantitative MS...how about
iodinated protein A quantization... |
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l**********1 发帖数: 5204 | 31 Continue:
even Plant Systems Biology also trying HMM approach:
In addition to the analysis of existing data sets, data inspection aims at
creating auxiliary data models that integrate prior knowledge, such as
contrast information, class labels, or even only loosely associated
observations. Models of this kind include Markov models, such as hidden
Markov models (HMM) or Markov random fields (MRF), and extensions of
prototype models, such as self-organizing maps (SOM), neural gas (NG), and
learnin... 阅读全帖 |
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l*****x 发帖数: 3431 | 32 比如我们用single precision floating point format, mantissa bit-width(或者
叫小数部分)是23位,能否调用某个函数来调整这个尾数的长度?
欧现在知道的是用fi,quantizer函数可以调整fixed point的整数/小数位数
谢谢! |
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b****e 发帖数: 4 | 34
has
Yes, image compression is a big part of image communications.
The scope of image communication usually covers:
Entropy Coding
Quantization
Transform Coding
Rate Control Techniques
Filter Banks and Wavelets
Scalable Compression
Standards: JBIG, JPEG, JPEG-2000
Motion-compensated coding,
MPEG standards
Digital video broadcasting
Internet video streaming |
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a****t 发帖数: 5 | 35 Recently, I have finished a paper on vector quantization codebook design.
Now I am looking for a conference or letter. So anybody have some suggestion
about the rest of this year's conference or letter. Thanks very much.
BTW, I am searching for people who get MIT's mater or PhD degree on EECS. I
am now in China, and I want to apply to MIT next fall. So I want to seek
some help on the application for MIT. Great thanks.
a************[email protected] |
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w*****s 发帖数: 842 | 36 Because H.264 supports many block mode and also quantization mode
for many prediction modes, which is reponsible for large block edge effects.
Also compared with previous standards, H.264 uses 4x4 transform instead of
8x8 transform most of the time. That's why deblock filtering is mandatory
for H.264. |
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p*****r 发帖数: 525 | 37 1. FIR 和 IIR filter FIXEDPOINT IMPLEMENTATION
哪种对Quantization noise 增加, 为什么? 答案是IIR, 原因?
2. ANALGUE CIRCUIT了有很多INTEGRATOR, 能不能直接用 1/(1-Z^(-1)) 代替, 为什
么?
两个连着的INTEGRATOR, 1/(1-Z^(-1)) -> 1/(1-Z^(-1)) , 能直接实现吗? 为什
么不能?
3. Bandpass signal, 比如carrier = 1GHZ, 带宽比如200KHz. 不考虑其他的BLOCK
signal, adjaceng interferer. 能不能用直接200KHZ sample rate, decretize. 用
NYQUIST定理, 理论上是没有ALIAS的。 为什么不能直接用 200KHZ 采样?
3. Complex MIXER
PLL信号 exp(j*w_c*t + c*sin(w_m*t)), c and w_m 都很小, 远小于 w_c, 频谱是
真么样的,如果PLL信号frequenc |
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f*********t 发帖数: 37 | 38 I think for the first question can be asked in another way:
FIR and IIR which one is easier for fixpoint implementation.
Then the answer should be FIR. The quatization noise will be accumulated in IIR filter. This means the quantization noise will get larger and larger when you do the filtering if you didn't do anything to prevent it.
2. Don't know
3. Basically for under sampling we always need anti alias filter to get rid of out of band noise which will be in band after sampling.
4. Don't know |
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a**i 发帖数: 419 | 39 不是特别懂。但我理解这是用bandpass filter的响应来代替spectral components。
理论上它们携带的信息是等效的。
32
to be spectral components!!! I didn't see an FFT between the filter bank and
the quantizer that transforms the time-domain samples to frequency domain.
Confused??
time-domain input samples transformed to frequency via the bandpass filters?
bandpass filters so they are transformed to the frequency domain by the MDCT |
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d*******n 发帖数: 369 | 40 I have a similar and fuzzy feeling as yours but I want to know the detailed
explanation and detailed implementation. I just couldn't find them online
and in books.
这里关键是携带的形式,quantizer 需要的是一个spectrum!
and
.
filters?
MDCT |
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d*******n 发帖数: 369 | 41 I have a similar and fuzzy feeling as yours but I want to know the detailed
explanation and detailed implementation. I just couldn't find them online
and in books.
这里关键是携带的形式,quantizer 需要的是一个spectrum!
这里没人玩Audio coding 的吗?
and
.
filters?
MDCT |
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le 发帖数: 190 | 42 why it has a white spectrum from DC to fs/2? |
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c**e 发帖数: 5555 | 43 there're presumptions for this conclusion. find a book about ADC and it
should be talked in the first chapter. |
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h********t 发帖数: 555 | 46 you are right. in reality, most noise energy is below fs/2, but there are
still some noise energy beyond fs/2. from design aspect, it is a good
assumption that all noise energy is below fs/2,so that you can be prepared
for the worst case. for high resolution A-D converters, the noise
performance actually is limited by thermal noise, not Q-noise.
to
independent |
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f*********t 发帖数: 37 | 47 Spectrum is from DC to fs/2. This is because after signal sampled at
sampling rate of fs at time domain, the power spectrum on frequency domain
will be pereiodically extended with period to be fs. This means the power
spectrum of the sampled signal is from [-fs/2 fs/2] is the same as [(n-1)*fs/2 (
n+1)fs/2]. Usually for descrete signal we only use the power spectrum in one
period.
Also for real baseband signal, after sampled, the spectrum will be symetric
to DC. so the spectrum [-fs/2 Dc] is the |
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c**e 发帖数: 5555 | 48 首先,白噪声是一种假设,当输入信号的变化足够快能keep ADC busy,并且和
sampling frequency是不相关的时候,可以认为量化噪声是平摊到nyquist带宽内的,
这样对分析设计有好处。
如果你问的是为什么有限带宽,sampling后的信号是离散的,带宽自然是有限,可以参
考信号系统知识和nyquist采样的定义。超过fs/2的能量被混叠回DC到fs/2的带内,类
似bouncing between DC and fs/2。 |
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f*********t 发帖数: 37 | 49 This is correct, hehe a concise explaination :) |
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le 发帖数: 190 | 50 If we treat the sampled data as discrete time sequence, can we assume we
have an impulse sampling circuit?
what you claimed is that the spectrum of the sampled data with impulse
sampling is band limited. That is not relevant to the original question. In
real world, even the spectrum of the sampled data is not band-limited to fs/
2 either, because you just can not implement a impulse sampling circuit. you
will have to either use sample and hold or sample and track circuit. in
that case, spectru |
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