Software Radio (SR) is one of the most important emerging technologies for the future of wireless communication services. By moving radio functionality into software, it promises to give flexible radio systems that are multi-service, multi- standard, multi-band, reconfigurable and reprogrammable by software. Today’s radios are matched to a particular class of signals that are well defined bytheircarrierfrequencies,modulationformatsandbandwidths.Aradiotransmitter today can only up convert signals with well-defined bandwidths over defined center frequencies, while, on the other side of the communication chain, a radio receiver can only down convert well-defined signal bandwidths, transmitted over specified carrier frequencies.
上傳時間: 2020-06-01
上傳用戶:shancjb
In this thesis several asp ects of space-time pro cessing and equalization for wire- less communications are treated. We discuss several di?erent metho ds of improv- ing estimates of space-time channels, such as temp oral parametrization, spatial parametrization, reduced rank channel estimation, b o otstrap channel estimation, and joint estimation of an FIR channel and an AR noise mo del. In wireless commu- nication the signal is often sub ject to intersymb ol interference as well as interfer- ence from other users.
標簽: Communications Space-Time Processing Wireless for
上傳時間: 2020-06-01
上傳用戶:shancjb
在互補式金氧半(CMOS)積體電路中,隨著量產製程的演進,元件的尺寸已縮減到深次微 米(deep-submicron)階段,以增進積體電路(IC)的性能及運算速度,以及降低每顆晶片的製造 成本。但隨著元件尺寸的縮減,卻出現一些可靠度的問題。 在次微米技術中,為了克服所謂熱載子(Hot-Carrier)問題而發展出 LDD(Lightly-Doped Drain) 製程與結構; 為了降低 CMOS 元件汲極(drain)與源極(source)的寄生電阻(sheet resistance) Rs 與 Rd,而發展出 Silicide 製程; 為了降低 CMOS 元件閘級的寄生電阻 Rg,而發展出 Polycide 製 程 ; 在更進步的製程中把 Silicide 與 Polycide 一起製造,而發展出所謂 Salicide 製程
標簽: Protection CMOS ESD ICs in
上傳時間: 2020-06-05
上傳用戶:shancjb
ESD is a crucial factor for integrated circuits and influences their quality and reliability. Today increasingly sensitive processes with deep sub micron structures are developed. The integration of more and more functionality on a single chip and saving of chip area is required. Integrated circuits become more susceptible to ESD/EOS related damages. However, the requirements on ESD robustness especially for automotive applications are increasing. ESD failures are very often the reason for redesigns. Much research has been conducted by semiconductor manufacturers on ESD robust design.
標簽: Guidelines Design Basic ESD
上傳時間: 2020-06-05
上傳用戶:shancjb
The term “ smart grid ” defi nes a self - healing network equipped with dynamic optimiza- tion techniques that use real - time measurements to minimize network losses, maintain voltage levels, increase reliability, and improve asset management. The operational data collected by the smart grid and its sub - systems will allow system operators to rapidly identify the best strategy to secure against attacks, vulnerability, and so on, caused by various contingencies. However, the smart grid fi rst depends upon identifying and researching key performance measures, designing and testing appropriate tools, and developing the proper education curriculum to equip current and future personnel with the knowledge and skills for deployment of this highly advanced system.
上傳時間: 2020-06-07
上傳用戶:shancjb
Software-defined radios (SDRs) have been around for more than a decade. The first complete Global Positioning System (GPS) implementation was described by Dennis Akos in 1997. Since then several research groups have presented their contributions. We therefore find it timely to publish an up-to-date text on the sub- ject and at the same time include Galileo, the forthcoming European satellite- based navigation system. Both GPS and Galileo belong to the category of Global Navigation Satellite Systems (GNSS).
標簽: A_Software-Defined_GPS_and_Galile o_Receiver
上傳時間: 2020-06-09
上傳用戶:shancjb
Agilent 34401A Service Guide.pdfIEC Measurement Category II includes electrical devices connected to mains at an outlet on a branch circuit. Such devices include most small appliances, test equipment, and other devices that plug into a branch outlet or socket. The 34401A may be used to make measurements with the HI and LO inputs connected to mains in such devices, or to the branch outlet itself (up to 300 VAC). However, the 34401A may not be used with its HI and LO inputs connected to mains in permanently installed electrical devices such as the main circuit-breaker panel, sub-panel disconnect boxes, or permanently wired motors. Such devices and circuits are subject to overvoltages that may exceed the protection limits of the 34401A. Note: Voltages above 300 VAC may be measured only in circuits that are isolated from mains. However, transient overvoltages are also present on circuits that are isolated from mains. The Agilent 34401A are designed to safely withstand occasional transient overvoltages up to 2500 Vpk. Do not use this equipment to measure circuits where transient overvoltages could exceed this level. Additional Notices Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/EC This product complies with the WEEE Directive (2002/96/EC) marking requirement. The affixed product label (see below) indicates that you must not discard this electrical/electronic product in domestic household waste. Product Category: With reference to the equipment types in the WEEE directive Annex 1, this product is classified as a "Monitoring and Control instrumentation" product. Do not dispose in domestic household waste. To return unwanted products, contact your local Agilent office, or see www.agilent.com/environment/product for more information. Agilent 34138A Test Lead Set The Agilent 34401A is compatible with the Agilent 34138A Test Lead Set described below. Test Lead Ratings Test Leads - 1000V, 15A Fine Tip Probe Attachments - 300V, 3A Mini Grabber Attachment - 300V, 3A SMT Grabber Attachments - 300V, 3A Operation The Fine Tip, Mini Grabber, and SMT Grabber attachments plug onto the probe end of the Test Leads. Maintenance If any portion of the Test Lead Set is worn or damaged, do not use. Replace with a new Agilent 3413
標簽: agilent
上傳時間: 2022-02-20
上傳用戶:
本系統采用電動機電樞供電回路串接采樣電阻的方式來實現對小型直流有刷電動機的轉速測量。該系統主要由二階低通濾波電路,小信號放大電路、單片機測量顯示電路、開關穩壓電源電路等組成。同時自制電機測速裝置,用高頻磁環作為載體,用線圈繞制磁環,利用電磁感應原理檢測電機運行時的漏磁,將變化的磁場信號轉化為磁環上的感應電流。用信號處理單元電路將微弱電信號轉化為脈沖信號,送由單片機檢測,從而達到準確測量電機的速度的要求。In this system, the sampling resistance of armature power supply circuit is connected in series to measure the speed of small DC brush motor. The system is mainly composed of second-order low-pass filter circuit, small signal amplifier circuit, single-chip measurement and display circuit, switching regulated power supply circuit and so on. At the same time, the self-made motor speed measuring device uses high frequency magnetic ring as the carrier, coil winding magnetic ring, and electromagnetic induction principle to detect the leakage of magnetic field during the operation of the motor, which converts the changed magnetic field signal into the induced current on the magnetic ring. The weak electric signal is transformed into pulse signal by signal processing unit circuit, which is sent to single chip computer for detection, so as to meet the requirement of accurate measurement of motor speed.
標簽: 直流電動機
上傳時間: 2022-03-26
上傳用戶:
三菱電機功率器件在工業、電氣化鐵道、辦公自動化、家電產品等多種領域的電力變換及電動機控制中得到廣泛應用。為了真正滿足市場對裝置噪音低、效率高、體積小、重量輕、精度高、功能強、容量大的要求,三菱電機積極致力于新型器件的研究、開發,為人類的節能和環保不斷努力。第5代IGBT和IPM模塊均采用三菱電機第5代IGBT硅片CSTBTIM技術,并具有正溫度系數特征,與傳統的溝槽型構造IGBT相比,降低了集電極一發射極間飽和電壓,從而實現了更低損耗。同時改進了封裝技術,大大減小了模塊內部分布電感。本應用手冊的出版,旨在幫助用戶了解第5代IGBT和IPM模塊的特性和工作原理,更加方便的使用三菱電機的半導體產品。三菱電機謹向所有購買和支持三菱半導體產品的用戶表示誠摯的感謝。1.IGBT模塊的一般認識1.1 NF系列IGBT模塊的特點NF系列IGBT模塊主要具有以下兩大特點:1,采用第5代IGBT硅片在溝槽型IGBT的基礎上增加電荷蓄積層的新結構(CSTBT)改善了關斷損耗(Eoff)和集電極-發射極問飽和電壓VEisat的折衷。插入式組合元胞(PCM)的使用增強了短路承受能力(SCSOA)并降低了柵極電容,從而降低驅動功率。CSTBT:Carrier Stored Trench-Gate Bipolar Transistor載流子存儲式溝槽硼型雙極晶體臂
標簽: igbt
上傳時間: 2022-06-19
上傳用戶:shjgzh
如何正確導入Spice模型方法一、將模型文件粘在當前的圖紙上,方法見圖:步驟1:復制模型文件(米源于OrCAD PSpice Model)步驟2:將復制的文件復制到下圖所示位置步驟3:點擊上面框圖中的OK,將文件粘貼在紙面上,然后從文件中拖一個三極管出來,將名字改成一樣即可。方法二、如有*.1ib的庫文件,比如PSPICE的日本晶體管庫jbipolar.lib,將該文件考到LTC LTspicelV\lib\sub目錄中。然后按圖操作:方法三:將模型文件直接粘貼到LTCYLTspiceIV\ib\cmp中的相應文件中。如要將PSPICE的diode.lib的模型全導入到cmp中的standard.dio中。先用記事本打開diode.1ib,全選,復制。而后用記事本打開standard,dio,在其適當的位置粘貼,關閉。發現二極管庫里多了很多元件(見下圖)。三極管同理。
上傳時間: 2022-06-22
上傳用戶: