窄帶物聯(lián)網(wǎng)(NB-IoT)窄帶物聯(lián)網(wǎng)（Narrow Band Internet of Things, NB-IoT）成為萬(wàn)物互聯(lián)網(wǎng)絡(luò)的一個(gè)重要分支。NB-IoT構(gòu)建于蜂窩網(wǎng)絡(luò)，只消耗大約180kHz的帶寬，可直接部署于GSM網(wǎng)絡(luò)、UMTS網(wǎng)絡(luò)或LTE網(wǎng)絡(luò)，以降低部署成本、實(shí)現(xiàn)平滑升級(jí)。 NB-IoT是IoT領(lǐng)域一個(gè)新興的技術(shù)，支持低功耗設(shè)備在廣域網(wǎng)的蜂窩數(shù)據(jù)連接，也被叫作低功耗廣域網(wǎng)(LPWAN)。NB-IoT支持待機(jī)時(shí)間長(zhǎng)、對(duì)網(wǎng)絡(luò)連接要求較高設(shè)備的高效連接。據(jù)說(shuō)NB-IoT設(shè)備電池壽命可以提高至少10年，同時(shí)還能提供非常全面的室內(nèi)蜂窩數(shù)據(jù)連接覆蓋。2017年7月13日，ofo小黃車(chē)與中國(guó)電信、華為共同宣布，三家聯(lián)合研發(fā)的NB-IoT（Narrow Band Internet of Things，窄帶物聯(lián)網(wǎng)）“物聯(lián)網(wǎng)智能鎖”全面啟動(dòng)商用。 [9] 據(jù)了解，在此次三方合作中，ofo負(fù)責(zé)智能鎖設(shè)備開(kāi)發(fā)，中國(guó)電信負(fù)責(zé)提供NB-IoT物聯(lián)網(wǎng)的商用網(wǎng)絡(luò)、華為負(fù)責(zé)芯片方面的服務(wù)。此前ofo已經(jīng)開(kāi)始使用這款物聯(lián)網(wǎng)智能鎖，而此次將啟動(dòng)全面的商用。
標(biāo)簽： NB-IOT
上傳時(shí)間： 2022-04-19
上傳用戶(hù)：
該步進(jìn)電機(jī)驅(qū)動(dòng)器又稱(chēng)為EasyDriver，EasyDriver能夠?yàn)閮杉?jí)步進(jìn)電機(jī)提供大約每相750mA（兩極一共1.5A）的驅(qū)動(dòng)。它默認(rèn)設(shè)置為8步細(xì)分模式（所以如果你的電機(jī)是每圈200步，你使用EasyDriver時(shí)默認(rèn)為每圈1600步），更多細(xì)分模式可以通過(guò)將MS1或MS2兩個(gè)接腳接地進(jìn)行設(shè)置。這是一種基于Allegro A3967驅(qū)動(dòng)芯片的細(xì)分?jǐn)嗦菲鳌?duì)于此設(shè)計(jì)的完整規(guī)格，請(qǐng)查閱A3967的參數(shù)表。它的最大每相電流從150mA到750mA。可以采用的最大驅(qū)動(dòng)電壓大概是30V，其中包括板載5V的調(diào)壓器，所以只需要一個(gè)電源。質(zhì)優(yōu)價(jià)廉，這玩意兒只要十幾美元，比你自己制作電路板更便宜。步進(jìn)電機(jī)驅(qū)動(dòng)器設(shè)計(jì)特色：· A3967 Microstepping Driver· MS1 and MS2 pins broken out to change microstepping resolution to full, half, quarter and eighth steps (defaults to eighth)· Compatible with 4, 6, and 8 wire stepper motors of any voltage· Adjustable current control from 150mA/phase to 700mA/phase· Power supply range from 6V to 30V. The higher the voltage, the higher the torque at high speeds
標(biāo)簽： 步進(jìn)電機(jī) 驅(qū)動(dòng)器 pcb 驅(qū)動(dòng)
上傳時(shí)間： 2022-04-27
上傳用戶(hù)：
LwM2M協(xié)議是OMA組織制定的輕量化的M2M協(xié)議，主要面向基于蜂窩的窄帶物聯(lián)網(wǎng)（Narrow Band Internet of Things, NB-IoT）場(chǎng)景下物聯(lián)網(wǎng)應(yīng)用，聚焦于低功耗廣覆蓋（LPWA）物聯(lián)網(wǎng)（IoT）市場(chǎng)，是一種可在全球范圍內(nèi)廣泛應(yīng)用的新興技術(shù)。具有覆蓋廣、連接多、速率低、成本低、功耗低、架構(gòu)優(yōu)等特點(diǎn)
標(biāo)簽： lwm2m協(xié)議
上傳時(shí)間： 2022-06-05
上傳用戶(hù)：kent
【摘要】介紹一種濾波器輔助設(shè)計(jì)軟件Filter Solutions，利用其設(shè)計(jì)一款常用的帶通濾波器，并將仿真曲線(xiàn)與實(shí)測(cè)結(jié)果進(jìn)行比較。【關(guān)鍵詞】Filter Solutions；濾波器；輔助設(shè)計(jì)Use Filter Solutions aid filter design Abstract:Introduce a software-Filter Solutions，which aid to design filter.Use it to digign a common band pass filter，then compare the result ofreslstemeasweothe simuetur，I1.Com Key words:Filter Solutions；filter；aid design1引言廣義上的濾波器深入到我們生活中的每一個(gè)角落，人眼對(duì)圖像的反應(yīng)符合低通濾波器的特征，人耳對(duì)聲音的反應(yīng)則符合帶通濾波器的特征。隨著近年來(lái)電子工業(yè)的飛速發(fā)展，濾波器已成為電子技術(shù)應(yīng)用中不可缺少的基礎(chǔ)器件之一，尤其廣泛地應(yīng)用于通信領(lǐng)域。能快捷而準(zhǔn)確地設(shè)計(jì)出預(yù)期特性的濾波器已成為所有電子工程師越來(lái)越強(qiáng)烈的需要。
標(biāo)簽： 濾波器 輔助設(shè)計(jì)
上傳時(shí)間： 2022-06-25
上傳用戶(hù)：
NB-IOT學(xué)習(xí)總結(jié)基于蜂窩的窄帶物聯(lián)網(wǎng)（Narrow Band Internet of Things，NB-loT）成為萬(wàn)物互聯(lián)網(wǎng)絡(luò)的一個(gè)重要分支。NB-loT構(gòu)建于蜂窩網(wǎng)絡(luò)，只消耗大約180KHz的帶寬，可直接部署于GSM網(wǎng)絡(luò)、UMTS網(wǎng)絡(luò)或LTE網(wǎng)絡(luò)，以降低部署成本、實(shí)現(xiàn)平滑升級(jí)。NB-loT是loT領(lǐng)域一個(gè)新興的技術(shù)，支持低功耗設(shè)備在廣域網(wǎng)的蜂窩數(shù)據(jù)連接，也被叫作低功耗廣域網(wǎng)（LPWA）（Low Power Wide Area，低功耗廣域技術(shù)）。NB-loT支持待機(jī)時(shí)間長(zhǎng)、對(duì)網(wǎng)絡(luò)連接要求較高設(shè)備的高效連接。據(jù)說(shuō)NB-loT設(shè)備電池壽命可以提高至至少10年，同時(shí)還能提供非常全面的室內(nèi)蜂窩數(shù)據(jù)連接覆蓋。一、NB-IOT架構(gòu)NB-loT端到端系統(tǒng)框架的建議
標(biāo)簽： NB-IoT
上傳時(shí)間： 2022-07-02
上傳用戶(hù)：
1. General Description BL-M3362NS1 product is designed base on Broadcom BCM43362 chipset. It operates at 2.4GHz band and supports IEEE802.11b/g/n 1T1Rwith wireless data rate up to 72.2Mbps. It supports IEEE802.11isafety protocol, along with IEEE802.11e standard service quality. It supports standard interfaces SDIOV2.0(50 MHz,4-bit and1-bit) and generic SPI(up to 50 MHz), Integrated ARM Cortex?-M3 CPUwith on-chip memory enables running IEEE802.11 firmware that can be field-upgraded with future features.2. The range of applying Imaging platforms(printers, digital still cameras, digital picture frames)Consumer electronic devices(DTV, DVDplayers, Blu-ray players. etc.)Gaming platforms Carinformation MiFi/Mobile Routes Smart PAD Set-TopBoxes
標(biāo)簽： wifi
上傳時(shí)間： 2022-07-04
上傳用戶(hù)：
PrefaceDuring the past years, there has been a quickly rising interest in radio access technologies for providingmobile as well as nomadic and fixed services for voice, video, and data. The difference indesign, implementation, and use between telecom and datacom technologies is also becoming moreblurred. One example is cellular technologies from the telecom world being used for broadband dataand wireless LAN from the datacom world being used for voice-over IP.Today, the most widespread radio access technology for mobile communication is digital cellular,with the number of users passing 5 billion by 2010, which is more than half of the world’s population.It has emerged from early deployments of an expensive voice service for a few car-borne users,to today’s widespread use of mobile-communication devices that provide a range of mobile servicesand often include camera, MP3 player, and PDA functions. With this widespread use and increasinginterest in mobile communication, a continuing evolution ahead is foreseen.This book describes LTE, developed in 3GPP (Third Generation Partnership Project) and providingtrue 4G broadband mobile access, starting from the first version in release 8 and through the continuingevolution to release 10, the latest version of LTE. Release 10, also known as LTE-Advanced,is of particular interest as it is the major technology approved by the ITU as fulfilling the IMTAdvancedrequirements. The description in this book is based on LTE release 10 and thus provides acomplete description of the LTE-Advanced radio access from the bottom up.Chapter 1 gives the background to LTE and its evolution, looking also at the different standardsbodies and organizations involved in the process of defining 4G. It also gives a discussion of the reasonsand driving forces behind the evolution.Chapters 2–6 provide a deeper insight into some of the technologies that are part of LTE and itsevolution. Because of its generic nature, these chapters can be used as a background not only for LTEas described in this book, but also for readers who want to understand the technology behind othersystems, such as WCDMA/HSPA, WiMAX, and CDMA2000.Chapters 7–17 constitute the main part of the book. As a start, an introductory technical overviewof LTE is given, where the most important technology components are introduced based onthe generic technologies described in previous chapters. The following chapters provide a detaileddescription of the protocol structure, the downlink and uplink transmission schemes, and the associatedmechanisms for scheduling, retransmission and interference handling. Broadcast operation andrelaying are also described. This is followed by a discussion of the spectrum flexibility and the associated
標(biāo)簽： 4g 移動(dòng)通信
上傳時(shí)間： 2022-07-08
上傳用戶(hù)：
NB86系列模塊是基于HISILICON Hi2115的Boudica芯片開(kāi)發(fā)的，該模塊為全球領(lǐng)先的NB-IoT無(wú)線(xiàn)通信模塊，符合3GPP標(biāo)準(zhǔn)，Hi2115芯片支持Band01，Band02，Band03，Band05、Band08、Band12，Band13，Band14，Band17，Band18，Band19，Band20、Band25，Band26，Band28，Band66頻段，具有體積小、功耗低、傳輸距離遠(yuǎn)、抗干擾能力強(qiáng)等特點(diǎn)。使用該模塊，可以方便客戶(hù)快速、靈活的進(jìn)行產(chǎn)品設(shè)計(jì)。本文檔中提供的NB86代表NB86-G等系列型號(hào)的統(tǒng)稱(chēng)，表2-1為NB86-G模塊支持的部分Band說(shuō)明。
標(biāo)簽： NB-IoT
上傳時(shí)間： 2022-07-11
上傳用戶(hù)：qingfengchizhu
MT7688 family integrates a 1T1R 802.11n Wi-Fi radio,a 580MHz MIPS? 24KEcTM CPU,1-port fast Ethernet PHY, USB2.0 host, PCIe, SD-XC,I2S/PCM and multiple slow IOs. MT7688 provides two operation modes-IoT gateway mode and IoT device mode. In IoT gateway mode, the PCI Express interface can connect to 802.1lac chipset for 1lac dual-band concurrent gateway. The high performance USB2.0 allows MT7688 to add 3G/LTE modem support or add a H.264 ISP for wireless IP camera. For the IoT device mode, MT7688 supports eMC, SD-XC and USB 2.0. MT7688 can support the Wifi high quality audio via 192Kbps/24bits I2S interface and VolP application through PCM. In IoT device mode, it further supports PWM, SPI slave,3d UARI and more GPIOs. For IoT gateway, it canl connect to touch panel and BLE, Zigbee/Z-Wave and sub-1G RF for smart home control.
上傳時(shí)間： 2022-07-24
上傳用戶(hù)：
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