The field of digital communication has evolved rapidly in the past few decades, with commercial applications proliferating in wireline communi- cation networks (e.g., digital subscriber loop, cable, fiber optics), wireless communication (e.g., cell phones and wireless local area networks), and stor- age media (e.g., compact discs, hard drives). The typical undergraduate and graduate student is drawn to the field because of these applications, but is often intimidated by the mathematical background necessary to understand communication theory.
標(biāo)簽： Communication Fundamentals Digital of
上傳時(shí)間： 2020-05-27
上傳用戶：shancjb
Wireless communications has become a field of enormous scientific and economic interest. Recent success stories include 2G and 3G cellular voice and data services (e.g., GSM and UMTS), wireless local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and digital broadcast systems (DVB, DAB, DRM). On the physical layer side, traditional designs typically assume that the radio channel remains constant for the duration of a data block. However, researchers and system designers are increasingly shifting their attention to channels that may vary within a block. In addition to time dispersion caused by multipath propagation, these rapidly time-varying channels feature frequency dispersion resulting from the Doppler effect. They are, thus, often referred to as being “doubly dispersive.”
標(biāo)簽： Time-Varying Channels
上傳時(shí)間： 2020-06-01
上傳用戶：shancjb
Electrostatic discharge (ESD) phenomena have been known to mankind since Thales of Miletus in approximately 600 B.C.E. noticed the attraction of strands of hay to amber. Two thousand six hundred years have passed and the quest to obtain a better under- standing of electrostatics and ESD phenomenon continues. Today, the manufacturing of microelectronics has continued the interest in the field of electrostatic phenomenon spanning factory issues, tooling, materials, and the microelectronic industry
標(biāo)簽： Devices Physics ESD and
上傳時(shí)間： 2020-06-05
上傳用戶：shancjb
Current field forecast verification measures are inadequate, primarily because they compress the comparison between two complex spatial field processes into one number. Discrete wavelet transforms (DWTs) applied to analysis and contemporaneous forecast fields prove to be an insightful approach to verification problems. DWTs allow both filtering and compact physically interpretable partitioning of fields. These techniques are used to reduce or eliminate noise in the verification process and develop multivariate measures of field forecasting performance that are shown to improve upon existing verification procedures.
標(biāo)簽： field forecast verification
上傳時(shí)間： 2020-07-22
上傳用戶：
RTL8111E是瑞昱的PCI-e接口千兆以太網(wǎng)芯片。引腳從48個(gè)，外圍電路簡(jiǎn)單，不需要外部EEPROM，MAC地址燒寫(xiě)更加方便。
標(biāo)簽： rtl8111e PCI-e 接口 以太網(wǎng)
上傳時(shí)間： 2021-12-11
上傳用戶：jiabin
開(kāi)關(guān)穩(wěn)壓電源（電子設(shè)計(jì)競(jìng)賽 E題）（內(nèi)附論文和PCB圖）
標(biāo)簽： 開(kāi)關(guān)電源
上傳時(shí)間： 2022-02-22
上傳用戶：
結(jié)構(gòu)體的具體尺寸如下所示：a=1.20h=0.620其中介質(zhì)錐的介電常數(shù)E=2.0。選定工作頻率為f=15GHz相對(duì)應(yīng)的真空中的波長(zhǎng)為0=20mm，這樣結(jié)構(gòu)體的兒何尺寸己經(jīng)完全確定，下面介紹求解的全過(guò)程選定求解方式為（Solution Type）Driven modal1.建立所求結(jié)構(gòu)體的幾何模型（單位：mm）。由于此結(jié)構(gòu)體的幾何形狀較簡(jiǎn)單，使用工具欄中的Draw命令可直接畫(huà)出，這里不再贅述述。畫(huà)出的結(jié)構(gòu)體如圖4.1.2所示。2.充結(jié)構(gòu)體的材料選定結(jié)構(gòu)體中的錐體部分，添加其介電常數(shù)Er=20的介質(zhì)材料注：如果HSS中沒(méi)有提供與所需參數(shù)完全相同的材料，用戶可以通過(guò)新建材料或修改已有材料，使其參數(shù)滿足用戶需求設(shè)定結(jié)構(gòu)體的邊界條件及其激勵(lì)源a.選定結(jié)構(gòu)體的貼片部分，設(shè)定其為理想導(dǎo)體（PerE）。b.畫(huà)出尺寸為X×Y×Z=70mm×70mm×40mm的長(zhǎng)方體作為輻射邊界，并設(shè)定其邊界條件為輻射邊界條件（Radiation Boundary）。c.由于要求出結(jié)構(gòu)體的RCS，因此設(shè)定激勵(lì)源為平面入射波（Incident Wave Source）。如圖4.1.3所示。4.設(shè)定求解細(xì)節(jié)，檢驗(yàn)并求解a.設(shè)定求解過(guò)程的工作頻率為f=15GHz.其余細(xì)節(jié)設(shè)定如圖4.1.4所示。b.設(shè)定遠(yuǎn)區(qū)輻射場(chǎng)的求解（Far Field Radiation Sphere欄的設(shè)定）。c.使用 Validation check命令進(jìn)行檢驗(yàn)，無(wú)錯(cuò)誤發(fā)生，下一步運(yùn)行命令 Analyze，對(duì)柱錐結(jié)構(gòu)體進(jìn)行求解。如圖4.1.5和4.1.6所示。
上傳時(shí)間： 2022-03-10
上傳用戶：
華碩H61M-E主板的BIOS程序，這種主板通病，官方網(wǎng)站下載下來(lái)的還需要分離，麻煩得很，這個(gè)直接能用！
上傳時(shí)間： 2022-03-22
上傳用戶：
CMOS.Analog.Circuit.Design.2e.by.P.E.Allen模擬集成電路的三大圣經(jīng)之一
標(biāo)簽： 模擬電路
上傳時(shí)間： 2022-05-04
上傳用戶：
本書(shū)以生動(dòng)活潑的形式，通俗地介紹了對(duì)數(shù)的發(fā)明和這一發(fā)明的重大意義，如何用它來(lái)解決實(shí)際問(wèn)題，以及常用對(duì)數(shù)的誕生和應(yīng)用。而更多的篇幅則留給了主角自然對(duì)數(shù)——它為什么和怎樣在整個(gè)科學(xué)中大放異彩，為什么數(shù)學(xué)家們要用E作自然對(duì)數(shù)的底，E究竟是一個(gè)什么樣的數(shù)……本書(shū)圖文并茂，將人文精神融入好玩的數(shù)學(xué)以至整個(gè)科學(xué)之中，妙趣橫生的情節(jié)引人入勝，讓讀者充分感受數(shù)學(xué)之真、之美、之樂(lè)、之用，適合于中等及以上文化的人閱讀。跟我走吧，現(xiàn)在就出發(fā)，穿過(guò)快樂(lè)的河流，就會(huì)到達(dá)E那不可思議的老家
標(biāo)簽： 數(shù)學(xué)
上傳時(shí)間： 2022-06-11
上傳用戶：
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