Wireless communication has become increasingly important not only for professional appli- cations but also for many fields in our daily routine and in consumer electronics. In 1990, a mobile telephone was still quite expensive, whereas today most teenagers have one, and they use it not only for calls but also for data transmission. More and more computers use wireless local area networks (WLANs), and audio and television broadcasting has become digital.
標簽: Applications and Theory OFDM CDMA of
上傳時間: 2020-06-01
上傳用戶:shancjb
Fourth Generation (4G) wireless communication systems aim to allow peak data rates in the range of 1 Gbps for nomadic access and 100 Mbps for vehicular mobil- ity. 4G aims to support current and emergent multimedia services, such as mobile TV, social networks and gaming, high-definition television and video telecon- ference, multimedia messaging service, using the All-over IP concept and with improved quality of service.
標簽: Transmission Techniques Systems for 4G
上傳時間: 2020-06-01
上傳用戶:shancjb
Second-generation telecommunication systems, such as the Global System for Mobile Communications (GSM), enabled voice traffic to go wireless: the number of mobile phones exceeds the number of landline phones and the mobile phone penetration is approaching 100% in several markets. The data-handling capabilities of second-generation systems are limited, however, and third-generation systems are needed to provide the high bit-rate services that enable high-quality images and video to be transmitted and received, and to provide access to the Web with higher data rates.
標簽: Evolution WCDMA UMTS HSPA LTE for and
上傳時間: 2020-06-01
上傳用戶:shancjb
Wireless networking is undergoing a transformation from what has been primarily a medium for supporting voice traffic between telephones, into what is increasingly becoming a medium for supporting traffic among a variety of digital devices transmitting media of many types (voice, data, images, video. etc.) Wireline networking underwent a similar transformation in the 1990s, which led to an enormous build-up in the capacity of such networks, primarily through the addition of new optical fiber, switches and other infrastructure.
標簽: Multiusers Detection Wireless Networks
上傳時間: 2020-06-01
上傳用戶:shancjb
The advent of modern wireless devices, such as smart phones and MID 1 terminals, has revolutionized the way people think of personal connectivity. Such devices encompass multiple applications ranging from voice and video to high-speed data transfer via wireless networks. The voracious appetite of twenty-first century users for supporting more wireless applications on a single device is ever increasing. These devices employ multiple radios and modems that cover multiple frequency bands and multiple standards with a manifold of wireless applications often running simultaneously.
標簽: Architectures Wireless Receiver Design and
上傳時間: 2020-06-01
上傳用戶: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.
標簽: Communications Management Wireless Resource
上傳時間: 2020-06-01
上傳用戶:shancjb
Sound is simply an airborne version of vibration. The air which carries sound is a mixture of gases. In gases, the molecules contain so much energy that they break free from their neighbors and rush around at high speed. As Figure 1.1(a) shows, the innumerable elastic collisions of these high-speed molecules produce pressure on the walls of any gas container. If left undisturbed in a container at a constant temperature, eventually the pressure throughout would be constant and uniform.
標簽: Engineering Audio
上傳時間: 2020-06-09
上傳用戶:shancjb
Although state of the art in many typical machine learning tasks, deep learning algorithmsareverycostly interms ofenergyconsumption,duetotheirlargeamount of required computations and huge model sizes. Because of this, deep learning applications on battery-constrained wearables have only been possible through wireless connections with a resourceful cloud. This setup has several drawbacks. First, there are privacy concerns. Cloud computing requires users to share their raw data—images, video, locations, speech—with a remote system. Most users are not willing to do this. Second, the cloud-setup requires users to be connected all the time, which is unfeasible given current cellular coverage. Furthermore, real-time applications require low latency connections, which cannot be guaranteed using the current communication infrastructure. Finally, wireless connections are very inefficient—requiringtoo much energyper transferredbit for real-time data transfer on energy-constrained platforms.
標簽: Embedded_Deep_Learning Algorithms
上傳時間: 2020-06-10
上傳用戶:shancjb
基于界面操作的人臉心率檢測的代碼,通過攝像頭實時采集人視頻,并計算心率(Face the heart rate detection interface operation based on the code, through real-time acquisition one camera video, and rate)
上傳時間: 2021-02-24
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2.7V to 5.5V input voltage Range? Efficiency up to 96% ? 24V Boost converter with 12A switch current Limit? 600KHz fixed Switching Frequency? Integrated soft-start? Thermal Shutdown? Under voltage Lockout? Support external LDO auxiliary power supply? 8-Pin SOP-PP PackageAPPLICATIONSPortable Audio Amplifier Power SupplyPower BankQC 2.0/Type CWireless ChargerPOS Printer Power SupplySmall Motor Power Supply
標簽: XR2981
上傳時間: 2021-11-05
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