During the past three decades, the world has seen signifi cant changes in the telecom- munications industry. There has been rapid growth in wireless communications, as seen by large expansion in mobile systems. Wireless communications have moved from fi rst-generation (1G) systems primarily focused on voice communications to third-generation (3G) systems dealing with Internet connectivity and multi-media applications. The fourth-generation (4G) systems will be designed to connect wire- less personal area networks (WPANs), wireless local area networks (WLANs) and wireless wide-area networks (WWANs).
標簽： Communications Networking Wireless
上傳時間： 2020-06-01
上傳用戶：shancjb
This book is concerned with integrated circuits and systems for wireless and mobile communications. Circuit techniques and implementation of reconfigurable low-voltage and low-power single-chip CMOS transceivers for multiband and multi- mode universal wireless communications are the focus of the book. Applications encompass both long-range mobile cellular communications (GSM and UMTS) and short-range wireless LANs (IEEE802.11 and Bluetooth). Recent advances in research into transceiver architecture, RF frontend, analogue baseband, RF CAD and automatic testing are reported.
標簽： Communication Wireless Circuits Systems and
上傳時間： 2020-06-01
上傳用戶：shancjb
The explosion in demand for wireless services experienced over the past 20 years has put significant pressure on system designers to increase the capacity of the systems being deployed. While the spectral resource is very scarce and practically exhausted, the biggest possibilities are predicted to be in the areas of spectral reuse by unlicensed users or in exploiting the spatial dimension of the wireless channels. The former approach is now under intense development and is known as the cogni- tive radio approach (Haykin 2005).
標簽： Multi-Antenna Wireless Channels Modeling
上傳時間： 2020-06-01
上傳用戶：shancjb
The planarization technology of Chemical-Mechanical-Polishing (CMP), used for the manufacturing of multi- level metal interconnects for high-density Integrated Circuits (IC), is also readily adaptable as an enabling technology in MicroElectroMechanical Systems (MEMS) fabrication, particularly polysilicon surface micromachining. CMP not only eases the design and manufacturability of MEMS devices by eliminating several photolithographic and film issues generated by severe topography, but also enables far greater flexibility with process complexity and associated designs. T
標簽： mechanical polishing Chemical
上傳時間： 2020-06-06
上傳用戶：shancjb
adio Frequency Identification (RFID) is a rapidly developing automatic wireless data-collection technology with a long history.The first multi-bit functional passive RFID systems,with a range of several meters, appeared in the early 1970s, and continued to evolve through the 1980s. Recently, RFID has experienced a tremendous growth,due to developments in integrated circuits and radios, and due to increased interest from the retail industrial and government.
標簽： RFID-Enabled Sensors RFID and
上傳時間： 2020-06-08
上傳用戶：shancjb
Radio frequency identification (RFID) and Wireless sensor networks (WSN) are the two key wireless technologies that have diversified applications in the present and the upcoming systems in this area. RFID is a wireless automated recognition technology which is primarily used to recognize objects or to follow their posi- tion without providing any sign about the physical form of the substance. On the other hand, WSN not only offers information about the state of the substance and environment but also enables multi-hop wireless communications.
標簽： Architecture Integrated RFID-WSN
上傳時間： 2020-06-08
上傳用戶：shancjb
PW4203 is a 4.5-22V input, 2A multi-cell synchronous Buck Li-Ion battery charger, suitable forportable application. Select pin is convenient for multi-cell charging. 800 kHz synchronous buckregulator integrates of 22V rating FETs with ultra low on- resistance to achieve high efficiency andsimple circuit design.The PW4203 is available in an 8-pin SOP package, provides a very compact system solution andgood thermal conductance
標簽： pw4203
上傳時間： 2022-02-11
上傳用戶：
基于藥物治療在臨床治療中的重要性,分析目前服藥提醒裝置存在的不足,以STM32F103VET6單片機為控制核心,設計了一種多功能電子藥箱。該系統包括顯示模塊、語音模塊和數據存儲模塊。顯示模塊通過觸摸屏電路和LED指示燈電路,與語音模塊相配合,實現了服藥提醒及指導的功能;數據存儲模塊通過EEPROM存儲電路,能夠實現掉電時服藥信息不丟失的功能。并且為了實現電子藥箱的智能化控制,開發了手機APP,兩者之間可通過WIFI進行數據通信。經測試,該藥箱能夠有效地幫助慢性病患者按時、定量、正確服用藥物,適合在家庭中推廣使用,具有較高的應用價值和實踐意義。Based on the importance of drug therapy in clinical treatment, this paper analyzes the shortcomings of current drug reminder devices, and designs a multi-function electronic medicine box with STM32 F103 VET6 microcontroller as the control core. The system includes a display module, a voice module, and a data storage module. The display module cooperates with the voice module through the touch screen circuit and the LED indicator circuit to realize the function of reminding and guiding the medicine;the data storage module can realize the function of not losing the medication information when the power is off through the EEPROM storage circuit.After testing, the medicine box can effectively help chronic diseases patients to take drugs on time, in a quantitative and correct manner,and is suitable for popularization in the family, and has high application value and practical significance.
標簽： 電子藥箱
上傳時間： 2022-03-27
上傳用戶：
多功能智能遙控窗簾系統廣泛地應用于家居、辦公室等場合,同時也是智能家居的一部分。該設計主要利用STC89C52單片機核心電路、光敏電阻電路、步進電機電路、溫濕度傳感器、紅外線控制電路、AD轉換電路、LCD1602液晶顯示屏等模塊完成精確控制窗簾的開和關。multi-functional intelligent remote control curtain system is widely used in home,office and other occasions,and is also part of intelligent home.The design mainly uses STC89 C52 single-chip core circuit,photosensitive resistor circuit,stepping motor circuit,temperature and humidity sensor,infrared control circuit,AD conversion circuit,LCD1602 LCD display and other modules to achieve accurate control of the curtain opening and closing.
上傳時間： 2022-03-28
上傳用戶：
說明： 51單片機控制智能溫控風扇，多檔調節，pwd調速。包含源碼和電路圖(51 single chip computer control intelligent temperature control fan, multi-stage adjustment, PWD speed regulation. Contains source code and circuit diagrams)
上傳時間： 2022-05-17
上傳用戶：
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