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Saturday, March 21, 2009

丰年虾

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丰年虾

丰年虾，又叫丰年虫、卤虫，隶属于节肢动物门，甲壳纲，鳃足亚纲，无甲目，丰年虫科。丰年虾广泛分布于陆地上的盐田或盐湖中，对于人工养殖的鱼虾，营养价值非常高。丰年虾的冬卵，更是一种很特别的休眠卵，可以晒干装罐，以商品形式上架销售，并且可以很方便地孵化出来，作为优质活饵料，丰年虾在水产养殖上应用甚广。

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丰年虾-基本介绍

丰年虾

丰年虾(ArtemiasalinaL.)分类上属于节肢动物门甲壳纲。由于它具有下列优点：

1.耐久卵大量采集容易，且可保存数年之久。
2.耐久卵孵化成无节幼虫(Nauplius)，只需约一天，培养容易。
3.为活饵，不易造成水质恶化。
4.不下沉，具有缓慢游泳能力。
5.大小适中。
6.含丰富的蛋白质和脂肪酸。

因此是鱼类、虾类等幼苗的良好饵料。

丰年虾-生态习性

丰年虾

丰年虾的分布为全球性，可见于世界各地的盐湖与咸水池中。在自然状况下，丰年虾很少发现在低于盐度千分之四十五的水中。丰年虾能生存于盐度千分之三百的水中，由于在高盐度下，捕食者和竞争者都很少，因此其族群能够维持很高的密度。

丰年虾在盐度千分之一百以上会产生直径约200~280微米的休眠卵，即一般俗称为耐久卵。耐久卵呈灰褐色，有坚硬的外壳，当漂浮于水面或悬浮于水中。能在水底污泥中渡过缺氧、寒冷、干燥等恶劣环境。在干燥及无氧的状态下，可保存数年之久，直到浸泡于海水中，壳内胚胎代谢被激发，才会孵化。

丰年虾对温度、盐度及溶氧的适应能力非常强，其可忍受的温度范围在6~35℃间；盐度为千分之五至千分之三百四十；溶氧则为1~150ppm之间。丰年虾最适的成长温度为25~30℃；pH值为7.5~8.5；盐度为千分之三十至千分之五十；溶氧则以接近饱和溶氧为佳。

耐久卵在28℃下约24小时可孵化成无节幼虫。刚孵出之无节幼虫体长约460微米，湿重约0.02毫克；孵化后5小时体长约720微米；孵化后24小时体长1220微米。在良好的环境下，丰年虾约9天即成熟。成熟时的丰年虾体长约1~1.2公分，湿重约10毫克。

丰年虾是雌雄异体，生殖方式可分为卵生及卵胎生两种。在高盐度及低溶氧等较差环境下，会诱导卵生，形成耐久卵。在低盐度、高溶氧下，受精卵会直接发育成无节幼虫。

丰年虾-耐久卵

丰年虾耐久卵孵化过程

丰年虾耐久卵品质的好坏，可依据下列几种方法予以判定：
(一)在温度25℃，盐度千分之三十五下检定
1.孵化率：即(每公克耐久卵所孵出之无节幼虫数)／(每公克耐久卵总数)×100%。
2.每公克耐久卵所孵出幼虫的总重量。
3.孵化效率：即每公克耐久卵所孵出之无节幼虫数。
4.无节幼虫最早出现所需之孵化时间。
5.90%无节幼虫孵出所需之时间。
6.孵出幼虫个体干重及个体所含热量高低。

(二)肉眼观察：以30倍放大镜察看砂粒、盐粒、破壳及羽毛等杂物的多寡。

(三)无节幼虫的大小。

(四)无节幼虫的营养价值。

耐久卵的去壳方法
丰年虾耐久卵的硬壳被仔鱼吞食后，会阻塞消化道，甚至造成种苗死亡，因此必须尽可能避免把卵壳掺杂无节幼虫，投入种苗池中。为减少卵壳的影响，可依下列步骤予以去壳。

1.耐久卵先用海水浸泡半小时。
2.耐久卵用滤布收集，去水分。
3.加入预冷为15~20℃之千分之二漂白水。
4.打气5~7分钟，或视卵壳由褐色变橘红色。
5.过滤收集、淡水冲洗。
6.每公升加入Na2S2O33公克中和。
7.打气5~7分钟。
8.过滤收集、淡水冲洗。
9.依平常方法将卵孵化。
经去壳处理后，耐久卵的硬壳被溶解，如此便可避免种苗吞食硬壳，造成死亡。

丰年虾-繁殖技术

丰年虾

丰年虾是两性繁殖，成年雄性丰年虾有一对大抓，紧紧抱著雌性丰年虾背部。一同不断地游水。可以产下卵胎生的无节幼虫或直接排卵。在直接排卵情况下，所产的卵又分夏卵和冬卵两种，夏卵产出后在水中迅速孵化为无节幼虫，跟母体直接产下的卵胎生无节幼虫基本相同。而冬卵则为休眠卵，，一般要在丰年虾的生存环境有比较大的变化时，比如降温，海水比重上升(即是水份蒸发，盐度越来越高)，食物缺乏等，化学药物刺激，丰年虾才会产下休眠卵。休眠卵有厚的卵壳，能忍耐恶劣的环境条件，一般不会在水中直接孵化，都需要经过一定的滞育期后，重新回到水中才能孵化，大部份丰年虾休眠卵为浮水性，采集方便。丰年虾种群就是用这种方式来抵抗恶劣环境，把后代以休眠卵的形式保护起来，到了环境恢复正常后才孵出。我们以商品形式购买到的丰年虾卵，就是休眠卵。休眠卵在低温干燥条件下保存，可以存活5年左右，当其重新进入常温海水中，或处于潮湿环境下吸收了水份，才会激发壳内的胚胎开始代谢活动，进入孵化过程，并最终破壳而出，成为无节幼虫。

丰年虾在早期的参考书籍中常被称为小海虾，为鱼类繁殖者最好的朋友，若是没有丰年虾的存在，在繁殖的工作上有极大的阻碍，它的无节幼虫(nauplii)为许多小鱼的第一餐最佳选择

丰年虾其实跟虾子一点关系都没有，而是挠脚类的一种，学名为Artemiasp.分布在世界各地的盐水湖泊中，在台南县北门乡的盐田中也有天然丰年虾存在，本身对盐度的适应范围极广，从千分之五到千分之九十都可存活(正常海水之盐度范围在千分之三十到千分之三十五之间)，在盐度较高时所产的卵具厚壁，可长期抗拒外界环境不利因子的伤害，保护其中休眠的胚胎，我们称之为耐久卵，也就是目前在市面上贩卖的丰年虾卵，等到环境适合丰年虾繁殖生存时，再破壁而出繁衍种族。丰年虾在繁殖上的应用已行之有年，其在繁殖鱼苗具有下列优点:
1.保存容易。
2.孵化方法简单，随时可进行大量孵化以提供鱼苗所需。
3.刚孵化的无节幼虫，大小及营养价值极符合各种鱼苗的需求。

1、准备工作
先准备一个养殖箱，容量从一两升至几十升都可以，装满海水鱼缸换出来的老水，也可以用海水盐来调成人工海水。放日光下暴晒，培养藻类，以作为丰年虾的食物来源。为了增加水中的有机质含量，可以把蛋白质分离器分离出来的废水添加进去，或者加点花肥也可以。一般情况，三至七天水就会变成绿色的了，说明藻类已经在生长。

2、加盐调成浓盐水
丰年虾是一种没有任何防御能力的生物，人的肉眼看不到的很多微生物都可以袭击它，把它吃掉。但丰年虾也有一个绝招，就是能生活在盐度很高的盐水中，自然界丰年虾生活的盐湖盐田中，盐度都很高，水中几乎没有其他生物可以生存下来。在家庭养殖中，可以把海水用粗盐调成大概比重1.07或更高。当然，也可以把海水煮沸蒸发成浓盐水。这一点是养殖成功的关键，好多人试养丰年虾没有成功，就是用的是普通盐度的海水。

3、其他设备
丰年虾的养殖几乎不需要任何设备。丰年虾能够在含氧量很低的环境中生存，一般不需要打气增氧，在夏天高温季节，水中溶氧量较小，如果养殖密度较大，投饵后剩饵有时会变质造成水中溶氧严重不足，这时也可以用气泵打气补氧，但丰年虾游戏能力很弱，打气不要形成太大的水流，否则丰年虾只能随着水流飘浮着，没办法自主摄食了。

丰年虾适应温度的范围也极广，在冰下的盐水中一样可以存活，夏天高达40度的情况下也不会导致大量死亡（如果高温下缺氧，也只是少量死亡），一般为了成本着想，就不必加温了。

丰年虾-孵化详解

丰年虾孵化

孵化的条件
一般市面上所买得到的丰年虾卵为其休眠卵，需经过外界刺激后才会活化，再孵化成无节幼虫，其中两个最重要的因子是盐度及温度。由于各厂牌丰年虾卵都是在自然界中直接采集而得的，由于各产地的丰年虾种并不一样，因此在孵化率及孵化时间上也会有差异存在，但基本上要成功孵化丰年虾最重要的是提供适当的盐度、温度、pH值(酸碱值)及足够的溶氧，以下将一一叙述：
１．盐度：千分之十到千分十五之间(10~15ppt)最佳，也就是每公升水中含有10~15公克的盐类，换算成比重大约在1.01~1.02之间(天然海水每公升含有30~35公克的盐类即30~35ppt，比重在1.022~1.026之间)。
２．温度：水温要在25~30℃之间，较高的温度有助于缩短孵化时间。
３．酸碱值：pH需在7.5~8.5之间
４．溶氧：一般需以打气使水如沸腾状以提供足够的溶氧(近乎饱和)。而孵化时间会随丰年虾品种及水温而有所不同，一般在18~36小时之间。
　　
使用的工具
１．孵化用水的事前准备
由于丰年虾需要在特定盐度之水中，才能唤醒其休眠卵，所以孵化用水的准备牵涉到孵化的成功与否，由于孵化时所需的盐度仅为天然海水的二分之一到三分之一而已，因此最简单的方法就是取用天然海水与淡水以1:1或1:2的比例混合即可。在天然海水无法取得之时，也可以市售之人工海水素依其建议之剂量先配成人工海水，再与淡水混合使用。此外由前述的条件可知，其实这个盐度也就是每公升含有十到十五公克的盐，因此我们也可在每公升的淡水中直接加入10~15克的食盐来使用，而一般浓缩洗衣粉所附的计量匙，每一匙大约可装40~45克的食盐左右，所以两公升的宝特瓶改装之孵化器大约需要添加八分满的一匙食盐即可。所有孵化用盐水的配制方法，如果可能最好都以比重计来检验其盐度，以确保比重维持在1.01到1.02之间。

孵化方法
目前孵化的方法有两种：
ａ．浅盘式孵化法：取一个长而浅的浅盘注入先前准备好的孵化用水，将丰年虾卵均匀洒在水面上，静置24~36小时后就会孵化成无节幼虫，收集时以光线聚集无节幼虫至盘之一端后以滴管收集备用，此法不适于大量孵化使用。
ｂ．深水式孵化法:取一个深且广的容器(两公升的宝特瓶)，注入准备好孵化用水，倒入适量的丰年虾卵，然后插入打气软管，以打气方式将水打滚，让虾卵在水中翻滚，经过24~36小时后就可孵化成无节幼虫，为目前最常见的方法。

丰年虾
孵化器的制作
一般市面上有特制的孵化器但颇为昂贵，在此特别提供DIY的方法，以提供与其相同的功能，以期节省您宝贵的金钱，方法如下：
ａ．取一个两公升的宝特瓶(最好是透明的如苹果西打或可口可乐的空瓶)，沿瓶底之塑料套裁开成漏斗状。
ｂ．将瓶盖以十字螺丝起子(直径与打气管相近)钉穿，制造一个气孔。
ｃ．将打气管穿透瓶盖，以硅胶固定并防漏水。
ｄ．将瓶盖(上硅胶放置24小时后)与漏斗状之瓶身锁紧即可使用。使用时将开口朝上加入丰年虾卵与孵化用水，再将打气管与打气机出风口相连即可，但需注意打气机放置位置不　得低于孵化器的水面，以防海水倒灌。

实际操作：(以两公升宝特瓶为例)
ａ．在宝特瓶中注入两公升淡水加入4/5匙的食盐。
ｂ．加入半匙的丰年虾卵(约4~5克)，不宜过多，过多会降低孵化的百分比。
ｃ．插入打气软管打气使水滚动。
ｄ．经过18小时后观察孵化情形。
注意事项：
Ⅰ．所使用单位(匙)为一匙灵等浓缩洗衣粉之计量匙。
Ⅱ．自制孵化器操作与上相同。
Ⅲ．不要使用气泡石来产生气泡,因为所生成的气泡过小，会使得丰年虾在孵化时所溶出的蛋白质产生聚集变成泡沫浮在水面，而使得丰年虾卵被吸附在蛋白质泡沫中，导致丰年虾因缺氧而死亡，降低孵化率。
Ⅳ．有研究者指出若先将丰年虾卵先以淡水浸泡一小段时间(不超过1小时)再进行孵化，可提高孵化率。

丰年虾-分离及收集

丰年虾幼虫

孵化后丰年虾的收集可使用浮游生物网 (60mesh以上)来进行，若无法取得浮游生物网时，可至美术材料行购买绢印用的绢布，即可用来收集丰年虾。此外由于未孵化的丰年虾卵及孵化后剩下的的空卵壳，对鱼苗而言都是无法消化的，所以需要将已孵出之无节幼虫与未孵化之卵及卵壳加以分离；当打气暂停一段时间后，由于比重上的差异，可观察到整瓶水可分成三层，由上而下分别为已孵出后剩下的空壳，像红色云雾状的无节幼虫群及未孵出或已死亡的丰年虾卵。因此我们可利用打气管直接以虹吸的原理将无节幼虫吸出至收集网中收集，如此即可获得极纯净的丰年虾，且由于无节幼虫有趋旋光性(有向光源聚集的本能)，因此在应用上可利用小灯泡放在孵化器的一侧来吸引无节幼虫聚集，以达较佳的分离效果。静置不打气的时间越长分离效果越佳，但静置过久不打气会导致刚孵化的丰年虾因缺氧死亡，一般而言大约在半小时到一小时之间为宜，但会随丰年虾卵孵化的程度不同而有变化，各位版友最好自行观察后再决定静置的时间。

喂食的最佳时机为鱼苗孵化后，刚把卵黄吸收完毕，可以开始自由游动时，大约是在孵化后第七、八天。投喂时需注意小鱼是否已有能力吃下丰年虾，有能力吃下丰年虾的小鱼通常在几分钟后，便可由目视观察到一个橘红色的大肚子。因此随时保有刚孵出的丰年虾以提供这些小生命救命的第一餐，是决定成败的关鉴，十八小时后丰年虾便开始渐渐孵出，一直到四十八小时以后才会停止孵出，因此在孵化丰年虾时最好分批孵化，批与批之间间隔6~24小时，如此可确保随时有刚孵出的无节幼虫以供利用。

丰年虾是可以自己养的。有专门出售饲养丰年虾的产品，包括丰年虾的饵食。若你不想花那么多钱买那些东东来养，可自己弄个缸子，用人工海水或粗盐加点硫酸镁制造出丰年虾需要的水质。丰年虾生长在比海水盐度还要高些的水域，通常是不定湖泊等。弄好缸子后打气并每日至少日照五小时，但夏天时要注意不要晒得太热了煮虾汤!等长出浓浓的绿藻后再将丰年虾卵放入水中，约一至二天就孵出来了。而丰年虾就吃绿藻长大，情况良好时可自行繁殖，就可用活丰年虾喂鱼又可维持很久了。但在培养绿藻时要加入绿藻所需的营养盐，可放些蔬菜或绿藻培养剂。

一般养殖丰年虾的海水比重在1.07以上，不需要特别关注。经过一段时间的蒸发，海水浓度较高时，丰年虾会相对颜色较红些，体型也较小些，营养价值不会有影响。

Saturday, March 14, 2009

cmos

Lecture Notes and Assignments

I have posted the lecture notes for each week in both 2-page and 3-page-with-notespace PDF formats. You can print whichever suits you. The 3-page per sheet is the PowerPoint format that gives you space to write notes beside each slide.

http://www.ele.uri.edu/Research/cherry/mentor_tutorial/

http://www.engr.uky.edu/~ee564/tutorials.htm

http://www.cse.sc.edu/~jimdavis/Courses/2005-Fall%20CSCE%20613/csce-613-fall05.htm

Lecture Week	Topics	Notes and Materials	Assignment
Week #01 (8/18)	Introduction to the subject material and the course.	Week-01 Lecture Notes (PDF): 2-page per sheet, 3-page per sheet.
Week #02 (8/23, 8/25)	Chapters 2 & 3 (start). Basic CMOS device topology and fabrication (Rabaey et al., 2002). Construction of digital logic gates in CMOS (Weste et al., 1994).	Week-02 Lecture Notes (PDF): 2-page per sheet, 3-page per sheet.	HW #1: Due 9/6. HW-01 Handout (PDF) Total 10 points.
Week #03 (8/30, 9/1)	Chapter 3, Rabaey et al. Discussion of device models for nMOS and pMOS transistors. See notes for the reading assignment.	Week-03 Lecture Notes (PDF): 2-page per sheet, 3-page per sheet.	HW #2: Due 9/13. HW-02 Handout (PDF) Total 10 points.
Week #04 (9/6, 9/8)	Chapter 3, continued. Discussion of device resistance and capacitance estimation models.	Week-04 Lecture Notes (PDF): 2-page per sheet, 3-page per sheet.	HW #3: Due 9/20. HW-03 Handout (PDF) Total 20 points.
Week #05 (9/13, 9/15)	Weste et al., Chapter 5. Discussion of transistor layout rules and examples of Boolean logic device layout using full-custom and semi-custom layout topologies.	Week-05 Lecture Notes (PDF): 2-page per sheet, 3-page per sheet.	HW #4: Due 9/27. HW-04 Handout (PDF) Total 20 points.
Week #06 (9/20, 9/22)	Rabaey, et al., Chapter 4. Discussion of wire models for the interconnect between devices and logic circuits.	Week-06 Lecture Notes (PDF): 2-page per sheet, 3-page per sheet.
Week #07 (9/27, 9/29)	Device modeling, parameterization from I-V curves, capacitance and working through homework problems.	Working design analysis problems in class. Discussing your questions on homework problems.
Week #08 (10/4, 10/6)	Tuesday: more problem-solving. Thursday: Design rules, some additional problems with capacitance and resistance.	We'll reference the problems in the Chapter from the Hodges et al. text. (Handed out two weeks ago).	Examples: Hodges, pp. 73, 78, 80. HW #5 Handout (PDF). Due 10/18.
Week #09 (10/11, 10/13)	Fall Break for part of this week.	We will will work on Assignment #4 in the lab Tuesday.	Have a good holiday and get caught up.
Week #10 (10/18, 10/20)	Power dissipation. Wire modeling - Capacitance.	We'll discuss use of design rules, and how the layout and analysis activities go together. Week 10 Lecture Notes (PDF).	HW #6 Handout (PDF). Due 10/27.
Week #11 (10/25, 10/27)	Wire modeling - Resistance. Inverters (again) - Capacitance. Exam: Review.	I'm at a conference on Tuesday, so take the time to work on assignments. Week 11 Lecture Notes (PDF). We'll discuss the exam on Thursday.	HW #7 Handout (PDF). Due 11/3. Additional Notes on HWs 6 & 7 (PDF).
Week #12 (11/1, 11/3)	Tuesday - Exam: 4 problems. Thursday: Inverters, Delay. Additional tutorials on Mentor Graphics.	Week 12 Lecture Notes (PDF).	HW #8 Mentor Tutorial: Assignment is to work through the Mentor tutorial (PDF), and turn in the output of this work process--screen dumps or printouts of created design artifacts and any other relevant output created as a result of the tutorials. For more practice with the tools, see the Mentor tutorial links at the bottom of this web page.
Week #13 (11/8, 11/10)	Projects	The project assignments come from a selection provided by the text authors, plus some that I have pulled from Rabaey et al., Chapter 11 on Computer Arithmetic combinational logic circuits. The best way to get into understanding the direct application of the material is to start on the projects. Information on the device library is given in the tutorials. Updated Mentor Design Architect tutorial document (PDF).	Here's a document discussing the project deliverables. Project Deliverables (PDF) document. Get the set of Project Guidelines (PDF) here, as they have the information about the project teams, assignment, reference materials, timeline, due dates, etc. that you will need to know. Here is the template for your project report, due at the end of the semester: Project Report Template (Word). Projects will be done in teams of two. Select a team partner.
Week #14 (11/15, 11/17)	Projects. Thursday: meet in lab 1D39.	Supplemental reading handout materials from Hodges et al. Updated Mentor Design Architect tutorial document (PDF). This is based on U. of KY web tutorial, modified for our setup.	Project Deliverables #1, 2 & 3. See the Project Deliverables & Project Guidelines documents for more information.
Week #15 (week 11/22)	Lab work on Mentor tutorial (Part 2) projects. Supplementary discussion of Hodges et al. chapters (I have Chapter 6 for you).	IC Design tutorial (PDF). This is based on U. of KY web tutorial, modified for our setup.	Project Deliverables #4 & 5. See the Project Deliverables document for more information.
Week #16 (11/29, 12/2)	Tuesday: Project work in the lab 1D39 Thursday: Discussion of Take-home exam component of the project. Discussion of the modeling and analysis of the ADDER circuits.		Project Deliverables #6 & 7. See the Project Deliverables document for more information.
Final Exam: Friday 12/9, 2:00 PM	We'll present the projects and turn in the Take Home portion of the project analysis.	Here's the Manuals for the Mentor Tools (Mentor Tools Page).	Project Final Report Due. See the Project Deliverables document for more information. Here is the template for your project report: Project Report Template (Word).

Wednesday, February 18, 2009

Communications Engineering

Tutorials in Communications Engineering

Please post your technical questions on the board. I am getting a lot of mail and am unable to answer your technical questions via email. Click here to go to board.

Please feel free to email me about errors and/or general comments, ideas on topics, and suggestions about these tutorials.

Tutorial 1 - Basic concepts in signal analysis, power, energy and spectrum (Revised Oct 2008)

Tutorial 2 - What is Differential Phase Shift Keying

Tutorial 3 - What is the DVB-S standard, a simplified version

Tutorial 4 - Fourier Analysis Made easy - Part 1

Tutorial 5 - Fourier Analysis Made easy - Part 2

Tutorial 6 - Fourier Analysis Made Easy - Part 3

Tutorial 7 - Hilbert Transform and the Complex Envelope

Tutorial 8 - All About Modulation - Part 1

Tutorial 9 - Baseband, Passband and Amplitude Modulation (AM)

Tutorial 10 - All about Traveling Wave Tube Amplifiers (TWTA) and non-linear amplification

Tutorial 11 - Link Budgets 101

Tutorial 12 - Convolutional Coding and Decoding Made Easy

Tutorial 13 - Coding Concepts and Block Coding

Tutorial 14 - Inter Symbol Interference (ISI) and Raised cosine filtering

Tutorial 15 - How to interpret an Eye diagram

Tutorial 16 - Partial Response signaling and Quadrature Partial Response (QPR) modulation

Tutorial 17 - Frequency Modulation (FM) , FSK, MSK and more

Tutorial 18 - Unlocking the Phase Locked Loop (PLL) - Part 1

Tutorial 19 - Unlocking the Phase Locked Loop (PLL) - Part 2

Tutorial 20 - Modulation performance metrics and computation of BER

Tutorial 21 - Linear Time Invariant systems and Matched filtering

Tutorial 22 - Orthogonal Frequency Division Multiplex (OFDM, DMT)

Tutorial 23a - About Lattice and cosets

Tutorial 23b - Trellis coded Modulation (TCM)

Tutorial 24 - Turbo Coding and MAP Decoding, Part 1
Part 2 - The MAP decoding algorithm, step-by-step
Companion worksheet

Tutorial 25 - CDMA

http://www.complextoreal.com/tutorial.htm

Digital modulation techniques

related topic: ADSL, Analog modulation techniques, Broadband modems, Digital TV, GSM, Modems, WIFI & WLAN, WLAN antennes, Wireless networking

Base de transmission numériques en Français

Communications analog and digital overview: a tip, animated

Communication systems and technology a tip

DAB DAB, Radio broadcasting systems, Digital Audio Broadcasting (DAB) to mobile, portable and fixed receivers, pdf

Digitally Modulated RF Systems a tutorial overview of various digital communication techniques currently applicable to Broadcasting, 16 QAM, Channel Capacity, Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK/QAM), pdf file

Digital modulation Digital modulation, Data Signal Analysis, Spectrum Analysis, pdf

Digital modulation direct sequence, Code Division Multiple Access (DS-CDMA), frequency hopping Code Division Multiple Access (FH-CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), pdf file

Digital modulation PSK, QPSK, OQPSK, M-PSK, MSK, GMSK, pdf file

Digital modulation ASK, FSK and PSK, Modulation techniques, QPSK, OQPSK, M-PSK, MSK, GMSK, pdf file

Digital modulation ASK, FSK and PSK, pdf file

Digital modulation, ASK, FSK and PSK

Digital modulation and GMSK Digital Modulation and GMSK, Phase shift keying, Quadrature Phase Shift Keying, Offset Quadrature Phase Shift Keying, OQPSK, Minimum Shift Keying, Gausssian Minimum Shift Keying (GMSK), GMSK Modulation, pdf file

Digital Modulation in Communications Systems how information is modulated onto in-phase (I) and quadrature (Q) signals, different types of digital modulation, an overview table with key specifications for the major digital communications systems, pdf file

Digital Modulation in Communications Systems pdf file

Digital modulation schemes pdf file

Digital modulation overview pdf file

Digital modulation techniques Digital modulation techniques, Amplitude shift key modulation (ASK), Frequency shift key modulation (FSK), Binary-phase shift key modulation (BPSK), Quadrature-phase shift key modulation (QPSK), Quadrature amplitude modulation (QAM)

Digital modulation techniques overview Digital modulation techniques overview

Digital Transmission of Analog Signals Digital Transmission of Analog Signals, Analog Pulse Modulation, pulse amplitude modulation (PAM), pulse width modulation (PWM) and pulse position modulation (PPM), Educypedia, sampling process, Digital Pulse Modulation, Pulse code modulation (PCM) and delta modulation (DM), Pulse Code Modulation, PCM Channel Banks, CCITT µ-Law, CCITT A-Law, PCM Transmission, pdf file

Ericsson technologies

Principles of digital modulation pdf file

Radio Communications

Reference for Wireless Communication Understanding Wireless Telecom and Data Communications Terminology, This reference will help you understand the terminology associated with wireless telecom and data communications, pdf file

Signal Processing for Cellular Communication Systems Data Flow Diagram, Amplitude Shift Keying, Frequency Shift Keying, Phase Shift Keying, Quadrature Amplitude Modulation, Flat fading, Multi-path fading

Tutorials in communications engineering signal analysis, power, energy and spectrum, Differential Phase Shift Keying, DVB-S standard, Fourier analysis, baseband - passband - and Amplitude Modulation (AM), Convolutional Coding and Decoding, coding concepts and block coding, inter symbol interference (ISI) and raised cosine filtering, Quadrature Partial Response (QPR) modulation, Frequency Modulation (FM) , FSK, MSK, Phase Locked Loop (PLL), Trellis coded Modulation (TCM)

Wireless LAN technologies Wireless LAN technologies, direct sequence, Code Division Multiple Access (DS-CDMA), frequency hopping Code Division Multiple Access (FH-CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), ppt file

Wireless Networking Measuring and Troubleshooting OFDM Wireless LAN Signal Quality, OFDM versus Single Carrier Modulation, Structure of IEEE 802.11a OFDM Frame, IEEE 802.11a Specifications, 64QAM

Horizontaal

Digital modulation: topics

related topics: ADSL, Broadband modems, GSM, Modulation techniques, WIFI & WLAN

16-QAM constellation diagram and bit allocation pdf file

64-QAM scheme 64-QAM scheme suitable for the transmission of cable televisions, Differential Coding And Mapping

Adaptive Modulation Adaptive Modulation (QPSK, QAM), pdf file

Amplitude-Shift Keying (ASK) Modulation pdf file

CDMA CDMA technique

CDMA CDMA History, Spread Spectrum Technology, Direct-Sequence Frequency Hopping, Time Hopping, CDMA Challenges, Receiver design, Near-Far Problem, Power Control, Soft and softer Handover, CDMA Applications in Mobile Network, ..., pdf file

CDMA Coding this applet demonstrates CDMA multiple access coding and allows the user to see the process of coding and decoding in real time

CDMA Interactive Interactive Flash Presentation covering various CDMA concepts

CDMA techniques CDMA techniques

CDMA technology the concept behind multiple access is to permit a number of users to share a common channel. The two traditional ways of multiple access are Frequency Division Multiple Access (FDMA) and Time Division Multiple Access (TDMA). CDMA, for Code Division Multiple Access, is different than those traditional ways in that it does not allocate frequency or time in user slots but gives the right to use both to all users simultaneously

CDMA tutorial Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA).

CDMA tutorial an introduction to Code Division Multiple Access (CDMA) communications, covering a Radio Carrier Station (RCS) and a Fixed Subscriber Unit (FSU), Introduction to Spread Spectrum Communications, Three Types of Spread Spectrum Communications, Direct Sequence Spread Spectrum, Implementing CDMA Technology

CDMA ppt file

Coded Orthogonal Frequency Division Multiplexing (COFDM) Variable Bit Rate Coding, VBR, Coded Orthogonal Frequency Division Multiplexing (COFDM), DAB, Wideband & Narrowband Wireless Transmission, Error Correction Coding, QPSK symbols, 16-QAM, 64-QAM

Coded Orthogonal Frequency Division Multiple Access pdf file

COFDM Coded Orthogonal Frequency Division Multiplexing (COFDM) is a form of modulation which is particularly well-suited to the needs of the terrestrial broadcasting channel, pdf file

Convolutional coding with Viterbi decoding a forward error correction technique known as convolutional coding with Viterbi decoding

Direct-Sequence Spread-Spectrum communications DSSS communications

Direct sequence vs. frequency hopping A Comparison of Frequency Hopping and Direct Sequence Spread Spectrum Modulation for IEEE 802.11 Applications at 2.4 GHz, pdf file

Discrete MultiTone transmission DMT

DPSK mode describes the sixteen-tone differential phase-shift keying (DPSK) mode

DSSS communications In telecommunications, direct-sequence spread spectrum is a modulation technique where the transmitted signal takes up more bandwidth than the information signal that is being modulated, which is the reason that it is called spread spectrum. DSSS, ...

DSSS: an Introduction to Direct-Sequence Spread-Spectrum Communications DSSS, A tutorial overview of spread spectrum principles. Covers both direct sequence and fast hopping methods. Educypedia, Theoretical equations are given to allow performance estimates. Relation to CDMA and TDMA is provided. Schematic of a code sequence generator is shown. Spectral plots are shown for DSSS and FHSS methods, pdf file

FDMA channel allocations

FREQUENCY CHANNEL ENCODING Pulse Modulation (PAM, PPM, and PFM)

FSK Frequency shift keying (FSK) is the most common form of digital modulation in the high-frequency radio spectrum, and has important applications in telephone circuits

FSK A quadrature modulator is a FSK modulator, Frequency shift keying modulator, pdf file

FSK: Signals and Demodulation FSK: Signals and Demodulation, Binary FSK is a modulation scheme typically used to send digital information between digital equipment such as teleprinters and computers, pdf file

GMSK Digital Modulation and GMSK, Gausssian Minimum Shift Keying (GMSK), pdf file

GMSK

GMSK Gaussian Minimum Shift Keying GMSK, Software Defined Radio, Modulation scheme used in GSM

GMSK Data Transmission Frequency Shift Keying FSK, Multi-level Frequency Shift Keying MFSK, Continuous Phase Frequency Shift Keying CPFSK, Minimum Shift Keying MSK, Gaussian Minimum Shift Keying GMSK, Tamed Frequency Modulation TFM, Phase Shift Keying PSK, Quadrature Phase Shift Keying QPSK, Differential Quadrature Phase Shift Keying DQPSK, Pi/4 Differential Quadrature Phase Shift Keying Pi/4 DQPSK, Quadrature Amplitude Modulation QAM, pdf file

GSM physical layer modulation GSM uses Gaussian-Fitered Minimum Shift Keying (GMSK) as it's modulation scheme

IQ modulation IQ modulation, modulation technique that lends itself well to digital processes is called "IQ Modulation", where "I" is the "in-phase" component of the waveform, and "Q" represents the quadrature component

Minimum Shift Keying Minimum Shift Keying [MSK] modulation --> a special form of FSK, pdf file

Minimum Shift Keying pdf file

Missing Cycle Modulation Pulse Position Phase Reversal Keying ( 3PRK ) pdf file

OFDM Modulation type of multi-carrier modulation

OOK, ASK and FSK Modulation pdf file

PCM tutorial puls code modulation

PSK Phase shifting a carrier in known steps to convey digital data

Phase-shift keying Phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal (the carrier wave)

Phase-shift keying Digital potentiometer controls phase shift

PSK Demodulation 1 PSK Demodulation

PSK Demodulation 2 PSK Demodulation

Puls code modulation ppt file

QPSK Modulation Demystified quadraphase-shift keying (QPSK)

QPSK modulation demystified Digital Frequency Modulation, Digital Phase Modulation, Quadraphase-Shift Modulation

Quadrature Amplitude Modulation Quadrature Amplitude Modulation, QAM, combination of amplitude modulation and phase shift keying

Quadrature modulators pdf file

Quadrature Amplitude Modulation Quadrature amplitude modulation, or QAM, is a big name for a relatively simply technique. It is simply a combination of amplitude modulation and phase shift keying

Quadrature amplitude modulation Quadrature amplitude modulation (QAM) is a modulation scheme which conveys data by changing (modulating) the amplitude of two carrier waves. These two waves, usually sinusoids, are out of phase with each other by 90° and are thus called quadrature carriers,

Quadrature signals and their importantance in Digital Signal Processing pdf file

QPSK Quadrature Phase Shift Keying (QPSK) modulation, a cosine carrier is varied in phase while keeping a constant amplitude and frequency

QPSK Phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal (the carrier wave), ...

Spread spectrum & CDMA tutorial spread spectrum & CDMA tutorial

Spread spectrum communication Frequency Hopping Techniques

Spread spectrum communication Direct sequence spread spectrum (DSSS), General Block Diagram, Direct Sequence Spread Spectrum (DSSS), Spreading and Despreading, Educypedia

Spread spectrum communications spread spectrum communications, A tutorial overview of spread spectrum principles. Covers both direct sequence and fast hopping methods. Theoretical equations are given to allow performance estimates. Relation to CDMA and TDMA is provided. Schematic of a code sequence generator is shown. Spectral plots are shown for DSSS and FHSS methods

Spread spectrum modulation Spread spectrum modulation, What is direct Sequence spread spectrum modulation

Spread Spectrum Modulation Techniques Direc-Sequence Spectrum (DS-SS) modulation techniques, Frequency-Hopped spread spectrum modulation techniques, pdf file

Spread Spectrum Modulation Techniques Introduction to Spread Spectrum Techniques

TDMA channel allocations Temporal Multiplexing, Synchronous Telegraphy

TDMA/FDMA ppt file

TDMA tutorial Time division multiple access (TDMA) is digital transmission technology that allows a number of users to access a single radio-frequency (RF) channel without interference by allocating unique time slots to each user within each channel

Techniques de codage NRZ, NRZI, MLT3, 2B1Q, Manchester, AMI, HDBx, nB/mB, FSK, ASK, QAM, FDM, TDM, WDM, DWDM, DMT, CAP, DWMT, a tip, en Français

Trellis coded Modulation (TCM) Trellis coded Modulation (TCM), pdf file

Trellis-Coded Modulation TCM, pdf file