Welcome to the world of wireless communications and the logical extension to the broadband architectures that are emerging as the future of the industry. No aspect of communications will be untouched by the wireless interfaces;no part of our working environment will be left untouched either. As the world changes and the newer technologies emerge, we can expect to see more in the line of untethered communications than in the wired inter- faces.
标签: Broadband Wireless Handbook
上传时间: 2020-06-01
上传用户:shancjb
Wirelesscommunications,especiallyinitsmobileform,hasbroughtusthefreedomofmobility andhaschangedthelifestylesofmodernpeople.Waitingatafixedlocationtoreceiveormakea phone call, or sitting in front of a personal computer to send an e-mail or download a video program, has become an old story. Nowadays it is commonplace for people to talk over a cell phonewhilewalkingonthestreet,ortodownloadandwatchamoviewhiletravelingonatrain. Thisisthebenefitmadeavailabletousbythesuccessfulevolutionofwirelesscommunications over three generations, with the fourth generation being under way.
标签: Communications Management Wireless Resource
上传时间: 2020-06-01
上传用户:shancjb
干耦合超声检测方法由于无需在待检测材料表面涂抹水或油等液体耦合剂,操作方便,移动灵活,适用于固体火箭发动机壳体、飞机机翼等一些对结构完整性要求较高且需要长期使用或贮存的部件。当利用干耦合方法对复合材料平板结构进行检测时,激发出的Lamb波携带有大量结构或缺陷的信息,如缺陷的类型、大小、位置等,采用合理的分析方法提取出信号中的有用信息,就能对材料中的损伤做出评估。
上传时间: 2021-10-18
上传用户:
The PW4554 is a cost-effective, fully integrated high input voltage single-cell Li-ion battery charger.The charger uses a CC/CV charge profile required by Li-ion battery. The charger accepts an inputvoltage up to 24V but is disabled when the input voltage exceeds the OVP threshold, typically 6.8V,to prevent excessive power dissipation. The 24V rating eliminates the over-voltage protection circuitrequired in a low input voltage charger
标签: pw4554
上传时间: 2022-02-11
上传用户:
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
标签: pw4203
上传时间: 2022-02-11
上传用户:
The PW4055 is a complete constant-current /constant-voltage linear charger for single cell lithiumion batteries.Its ThinSOT package and low external component count make the PW4055 ideallysuited for portable applications.Furthermore, the PW4055 is specifically designed to work within USBpower specifications.The PW4055 No external sense resistor is needed, and no blocking diode is required due to theinternal MOSFET architecture.Thermal feedback regulates the charge current to limit the dietemperature during high power operation or high ambient temperature. The charge voltage is fixedat 4.2V, and the charge current can be programmed externally with a single resistor. The PW4055automatically terminates the charge cycle when the charge current drops to 1/10th the programmedvalue after the final float voltage is reached. When the input supply (wall adapter or USB supply) isremoved, the PW4055 automatically enters a low current state, dropping the battery drain currentto less than 2µA. The PW4055 can be put into shutdown mode, reducing the supply current to 25µA.The BAT pin has a 7KV ESD(HBM) capability. Other features include charge current monitor, undervoltage lockout, automatic recharge and a status pin to indicate charge termination and the presenceof an input voltage
标签: pw4055
上传时间: 2022-02-11
上传用户:jason_vip1
The PW3130 series product is a high integration solution for lithium-lion/polymer batteryprotection.PW3130 contains advanced power MOSFET, high-accuracy voltage detection circuits anddelay circuits. PW3130 is put into an ultra-small SOT23-5 package and only one external componentmakes it an ideal solution in limited space of battery pack. PW3130 has all the protection functionsrequired in the battery application including overcharging, overdischarging, overcurrent and loadshort circuiting protection etc. The accurate overcharging detection voltage ensures safe and fullutilization charging.The low standby current drains little current from the cell while in storage. Thedevice is not only targeted for digital cellular phones, but also for any other Li-Ion and Li-Polybattery-powered information appliances requiring long-term battery life
标签: pw3130
上传时间: 2022-02-11
上传用户:fliang
The PW2301A uses advanced trench It utilizes the latest processing techniques to achieve the highcell density and reduces the on-resistance with high repetitive avalanche rating. These featurescombine to make this design an extremely efficient and reliable device for use in power switchingapplication and a wide variety of other applications
标签: pw2301a
上传时间: 2022-02-11
上传用户:
The PW8205A8TS is the highest performance trench N-ch MOSFETs with extreme high cell density,which provide excellent RDSON and gate charge for most of the small power switching and loadswitch applications. The meet the RoHS and Product requirement with full function reliabilityapproved .
标签: 8205a8
上传时间: 2022-02-14
上传用户:wangshoupeng199
5G通信技术白皮书技术资料合集摘 要 5G 致力于应对 2020 后多样化差异化业务的巨大挑战,满足超高速率、超低时延、高速移动、高能效 和超高流量与连接数密度等多维能力指标。FuTURE 论坛 5G 特别兴趣组(SIG)围绕着“柔性、绿色、极 速”的 5G 愿景,以“5+2”技术理念,重新思考 5G 网络的设计原则: 1) 香农理论再思考(Rethink Shannon):为无线通信系统开启绿色之旅 2) 蜂窝再思考(Rethink Ring & Young):蜂窝不再(no more cell) 3) 信令控制再思考(Rethink signaling & control):让网络更智能 4) 天线再思考(Rethink antennas):通过 SmarTIle 让基站隐形 5) 频谱空口再思考(Rethink spectrum & air interface):
标签: 5G通信
上传时间: 2022-03-06
上传用户: