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為了在CDMA系統(tǒng)中更好地應(yīng)用QDPSK數(shù)字調(diào)制方式，在分析四相相對移相（QDPSK)信號調(diào)制解調(diào)原理的基礎(chǔ)上，設(shè)計(jì)了一種QDPSK調(diào)制解調(diào)電路，它包括串并轉(zhuǎn)換、差分編碼、四相載波產(chǎn)生和選相、相干解調(diào)、差分譯碼和并串轉(zhuǎn)換電路。在MAX+PLUSⅡ軟件平臺(tái)上，進(jìn)行了編譯和波形仿真。綜合后下載到復(fù)雜可編程邏輯器件EPM7128SLC84-15中，測試結(jié)果表明，調(diào)制電路能正確選相，解調(diào)電路輸出數(shù)據(jù)與QDPSK調(diào)制輸入數(shù)據(jù)完全一致，達(dá)到了預(yù)期的設(shè)計(jì)要求。
Abstract:
In order to realize the better application of digital modulation mode QDPSK in the CDMA system， a sort of QDPSK modulation-demodulation circuit was designed based on the analysis of QDPSK signal modulation-demodulation principles. It included serial/parallel conversion circuit, differential encoding circuit, four-phase carrier wave produced and phase chosen circuit, coherent demodulation circuit, difference decoding circuit and parallel/serial conversion circuit. And it was compiled and simulated on the MAX+PLUSⅡ software platform,and downloaded into the CPLD of EPM7128SLC84-15.The test result shows that the modulation circuit can exactly choose the phase，and the output data of the demodulator circuit is the same as the input data of the QDPSK modulate. The circuit achieves the prospective requirement of the design.
標(biāo)簽：
QDPSK
CPLD
調(diào)制解調(diào)
電路設(shè)計(jì)
上傳時(shí)間：
2013-10-28
上傳用戶：jyycc
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半導(dǎo)體的產(chǎn)品很多，應(yīng)用的場合非常廣泛，圖一是常見的幾種半導(dǎo)體元件外型。半導(dǎo)體元件一般是以接腳形式或外型來劃分類別，圖一中不同類別的英文縮寫名稱原文為
PDID：Plastic Dual Inline Package
SOP：Small Outline Package
SOJ：Small Outline J-Lead Package
PLCC：Plastic Leaded Chip Carrier
QFP：Quad Flat Package
PGA：Pin Grid Array
BGA：Ball Grid Array
雖然半導(dǎo)體元件的外型種類很多，在電路板上常用的組裝方式有二種，一種是插入電路板的銲孔或腳座，如PDIP、PGA，另一種是貼附在電路板表面的銲墊上，如SOP、SOJ、PLCC、QFP、BGA。
從半導(dǎo)體元件的外觀，只看到從包覆的膠體或陶瓷中伸出的接腳，而半導(dǎo)體元件真正的的核心，是包覆在膠體或陶瓷內(nèi)一片非常小的晶片，透過伸出的接腳與外部做資訊傳輸。圖二是一片EPROM元件，從上方的玻璃窗可看到內(nèi)部的晶片，圖三是以顯微鏡將內(nèi)部的晶片放大，可以看到晶片以多條銲線連接四周的接腳，這些接腳向外延伸並穿出膠體，成為晶片與外界通訊的道路。請注意圖三中有一條銲線從中斷裂，那是使用不當(dāng)引發(fā)過電流而燒毀，致使晶片失去功能，這也是一般晶片遭到損毀而失效的原因之一。
圖四是常見的LED，也就是發(fā)光二極體，其內(nèi)部也是一顆晶片，圖五是以顯微鏡正視LED的頂端，可從透明的膠體中隱約的看到一片方型的晶片及一條金色的銲線，若以LED二支接腳的極性來做分別，晶片是貼附在負(fù)極的腳上，經(jīng)由銲線連接正極的腳。當(dāng)LED通過正向電流時(shí)，晶片會(huì)發(fā)光而使LED發(fā)亮，如圖六所示。
半導(dǎo)體元件的製作分成兩段的製造程序，前一段是先製造元件的核心─晶片，稱為晶圓製造；後一段是將晶中片加以封裝成最後產(chǎn)品，稱為IC封裝製程，又可細(xì)分成晶圓切割、黏晶、銲線、封膠、印字、剪切成型等加工步驟，在本章節(jié)中將簡介這兩段的製造程序。
標(biāo)簽：
封裝
IC封裝
制程
上傳時(shí)間：
2013-11-04
上傳用戶：372825274
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ACPR (adjacent channel power ratio), AltCPR (alternatechannel power ratio), and noise are important performancemetrics for digital communication systems thatuse, for example, WCDMA (wideband code division multipleaccess) modulation. ACPR and AltCPR are bothmeasures of spectral regrowth. The power in the WCDMAcarrier is measured using a 5MHz measurement bandwidth;see Figure 1. In the case of ACPR, the total powerin a 3.84MHz bandwidth centered at 5MHz (the carrierspacing) away from the center of the outermost carrier ismeasured and compared to the carrier power. The resultis expressed in dBc. For AltCPR, the procedure is thesame, except we center the measurement 10MHz awayfrom the center of the outermost carrier.
標(biāo)簽：
AltCPR
WCDMA
5528
ACPR
上傳時(shí)間：
2013-11-02
上傳用戶：maricle
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基本的編輯工具(GENERAL EDITING FACILITIES)
對象放置(Object Placement)
ISIS支持多種類型的對象，每一類型對象的具體作用和功能將在下一章給出。雖然類型不同，但放置對象的基本步驟都是一樣的。
放置對象的步驟如下(To place an object:)
1.根據(jù)對象的類別在工具箱選擇相應(yīng)模式的圖標(biāo)(mode icon)。
2. Select the sub-mode icon for the specific type of object.
2、根據(jù)對象的具體類型選擇子模式圖標(biāo)(sub-mode icon)。
3、如果對象類型是元件、端點(diǎn)、管腳、圖形、符號或標(biāo)記，從選擇器里(selector)選擇你想要的對象的名字。對于元件、端點(diǎn)、管腳和符號，可能首先需要從庫中調(diào)出。
4、如果對象是有方向的，將會(huì)在預(yù)覽窗口顯示出來，你可以通過點(diǎn)擊旋轉(zhuǎn)和鏡象圖標(biāo)來調(diào)整對象的朝向。
5、最后，指向編輯窗口并點(diǎn)擊鼠標(biāo)左鍵放置對象。對于不同的對象，確切的步驟可能略有不同，但你會(huì)發(fā)現(xiàn)和其它的圖形編輯軟件是類似的，而且很直觀。
選中對象(Tagging an Object)
用鼠標(biāo)指向?qū)ο蟛Ⅻc(diǎn)擊右鍵可以選中該對象。該操作選中對象并使其高亮顯示，然后可以進(jìn)行編輯。
標(biāo)簽：
Proteus
教程
基本概念
上傳時(shí)間：
2013-11-09
上傳用戶：2525775
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如果已經(jīng)安裝好了vobsub，就可以運(yùn)用vobsub里面帶的字幕提取工具vsrip提取字幕。
打開VobSub程序組,運(yùn)行vobsub.configure,點(diǎn)擊Open來打開vts_01_0.ifo文件(此文件已經(jīng)拷貝到硬盤上,無需從光盤上找),選定放置字幕文件的子目錄,點(diǎn)擊確定.提取完成之后會(huì)生成Vts_01_0.sub和vts_01_0.idx兩個(gè)字幕文件,若按照DVDrip的做法是在最終視頻文件生成之后,將字幕文件更名并與主體一致,但在此這個(gè)步驟被提前了,因?yàn)閞eal格式文件的字幕是嵌入在畫面那的.我們需要做的是將vts_01_0.idx和vts_01_0.sub更名為vts_01_1.idx和vts_01_1.sub,與vts_01_1.vob同名.這樣才能進(jìn)行制作時(shí)被vobsub自動(dòng)調(diào)用同步嵌入字幕
標(biāo)簽：
vobsub
上傳時(shí)間：
2015-04-28
上傳用戶：wangdean1101
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VHDL 關(guān)于2DFFT設(shè)計(jì)程序
u scinode1 ∼ scinode9.vhd: Every SCI node RTL vhdl code. The details can be
seen in the following section.
u 2dfft.vhd: The top module includes these scinodes and form a 3x3 SCI Torus
network, and it support these sub-modules scinode1∼ scinode9 reset and clk
and global_cnt signals to synchronous the sub-modules to simplify the overall
design.
u proj2.wfc: VSS simulation result that is the same as the ModelSim simulation
result.
u Pro2_2.wfc: VSS simulation result of another test pattern can’t cause overflow
situation.
標(biāo)簽：
scinode1
scinode
details
2DFFT
上傳時(shí)間：
2014-12-02
上傳用戶：15071087253
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his folder contains the following files:
1. 02490rxP802-15_SG3a-Channel-Modeling-Subcommittee-Report-Final.doc: This is the final
report of the channel modeling sub-committee.
2. cmx_imr.csv (x=1, 2, 3, and 4) represent the files containing the actual 100 channel
realizations for CM1, CM2, CM3, and CM4. The columns are organized as (time, amp, time, amp,...)
3. cmx_imr_np.csv (x=1, 2, 3, and 4) represent the files containing the number of paths in
each of the 100 multipath realizations.
4. cmx_imr.mat (x=1, 2, 3, and 4) are the .mat files that can be loaded directly into
Matlab (TM).
5. *.m files are the Matlab (TM) files used to generate the various channel realizations.
標(biāo)簽：
a-Channel-Modeling-Subcommittee-R
following
contains
folder
上傳時(shí)間：
2013-12-21
上傳用戶：hxy200501
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一種基于二維鏈表的稀疏矩陣模半板類設(shè)計(jì)
A template Class of sparse matrix.
Key technology: bin,2-m linked matrix.
constructors: 1.normal constuctor 2.copy constuctor. 3.assignment constructor.
Basic operator: 1. addition(sub) of two matrix
2. inverse of a matrix.
3. multiply of two matrix.
etc.
標(biāo)簽：
matrix
technology
template
linked
上傳時(shí)間：
2013-12-13
上傳用戶：lwwhust
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Wavelets have widely been used in many signal and image processing applications. In this paper, a new
serial-parallel architecture for wavelet-based image compression is introduced. It is based on a 4-tap wavelet
transform, which is realised using some FIFO memory modules implementing a pixel-level pipeline
architecture to compress and decompress images. The real filter calculation over 4 · 4 window blocks is
done using a tree of carry save adders to ensure the high speed processing required for many applications.
The details of implementing both compressor and decompressor sub-systems are given. The primarily analysis
reveals that the proposed architecture, implemented using current VLSI technologies, can process a
video stream in real time.
標(biāo)簽：
applications
processing
Wavelets
widely
上傳時(shí)間：
2014-01-22
上傳用戶：hongmo
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Blind Equalizer 的演算法主要是利用CMA及 LMS 的配合，當(dāng)CMA將EYE打開，使訊號趨近于正確值，就切換到LMS，利用Slicer的輸出當(dāng)作training sequence來調(diào)整Equalizer的系數(shù)，而Carrier Recovery 的部份，則是將phase error track出來
標(biāo)簽：
Equalizer
Blind
CMA
LMS
上傳時(shí)間：
2013-12-28
上傳用戶：it男一枚
