In 揚erformance of multi-carrier DS CDMA Systems?we apply a multi-carrier signaling technique to a direct-sequence CDMA system, where a data sequence multiplied by a spreading sequence modulates multiple carriers, rather than a single carrier. The receiver provides a correlator for each carrier, and the outputs of the correlators are combined with a maximal-ratio combiner. This type of signaling has the desirable properties of exhibiting a narrowband interference suppression effect, along with robustness to fading, without requiring the use of either an explicit RAKE structure or an interference suppression filter.
标签: multi-carrier erformance signaling technique
上传时间: 2017-07-31
上传用户:宋桃子
The TAS3204 is a highly-integrated audio system-on-chip (SOC) consisting of a fully-programmable, 48-bit digital audio processor, a 3:1 stereo analog input MUX, four ADCs, four DACs, and other analog functionality. The TAS3204 is programmable with the graphical PurePath Studio™ suite of DSP code development software. PurePath Studio is a highly intuitive, drag-and-drop environment that minimizes software development effort while allowing the end user to utilize the power and flexibility of the TAS3204’s digital audio processing core. TAS3204 processing capability includes speaker equalization and crossover, volume/bass/treble control, signal mixing/MUXing/splitting, delay compensation, dynamic range compression, and many other basic audio functions. Audio functions such as matrix decoding, stereo widening, surround sound virtualization and psychoacoustic bass boost are also available with either third-party or TI royalty-free algorithms. The TAS3204 contains a custom-designed, fully-programmable 135-MHz, 48-bit digital audio processor. A 76-bit accumulator ensures that the high precision necessary for quality digital audio is maintained during arithmetic operations. Four differential 102 dB DNR ADCs and four differential 105 dB DNR DACs ensure that high quality audio is maintained through the whole signal chain as well as increasing robustness against noise sources such as TDMA interference. The TAS3204 is composed of eight functional blocks: Clocking System Digital Audio Interface Analog Audio Interface Power supply Clocks, digital PLL I2C control interface 8051 MCUcontroller Audio DSP – digital audio processing 特性 Digital Audio Processor Fully Programmable With the Graphical, Drag-and-Drop PurePath Studio™ Software Development Environment 135-MHz Operation 48-Bit Data Path With 76-Bit Accumulator Hardware Single-Cycle Multiplier (28 × 48)
上传时间: 2016-05-06
上传用户:fagong
Device-to-device(D2D) communications are now considered as an integral part of future 5G networks which will enable direct communication between user equipment (UE) without unnecessary routing via the network infrastructure. This architecture will result in higher throughputs than conventional cellular networks, but with the increased potential for co-channel interference induced by randomly located cellular and D2D UEs.
标签: Device-to-Device Communications Analysis of
上传时间: 2020-05-26
上传用户:shancjb
Communication today is not as easy as it was in the past. Protecting numerous com- munication services, which are operating in the same or adjacent communication channels, has become increasingly challenging. Communication systems have to be protected from both natural and manmade interference. Electromagnetic interfer- ence can be radiated or conducted, intentional or unintentional.
标签: Communication Protection Systems EMI for
上传时间: 2020-05-27
上传用户:shancjb
Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.
标签: Communication Optical System Space Free
上传时间: 2020-05-27
上传用户:shancjb
The recent developments in full duplex (FD) commu- nication promise doubling the capacity of cellular networks using self interference cancellation (SIC) techniques. FD small cells with device-to-device (D2D) communication links could achieve the expected capacity of the future cellular networks (5G). In this work, we consider joint scheduling and dynamic power algorithm (DPA) for a single cell FD small cell network with D2D links (D2DLs). We formulate the optimal user selection and power control as a non-linear programming (NLP) optimization problem to get the optimal user scheduling and transmission power in a given TTI. Our numerical results show that using DPA gives better overall throughput performance than full power transmission algorithm (FPA). Also, simultaneous transmissions (combination of uplink (UL), downlink (DL), and D2D occur 80% of the time thereby increasing the spectral efficiency and network capacity
标签: Full-Duplex Cells Small
上传时间: 2020-05-27
上传用户:shancjb
We were on the lookout for ice. I was in a 32 foot sailing yacht with writer and explorer Tristan Gooley, undertaking a double-handed sail from Scotland through the Faroes up to 66 33 45.7 N and the midnight sun. Now sailing out of the Arctic Circle we were approaching Iceland from the north, heading for the Denmark Straits, where ice flowed south. The Admiralty Pilot warned of bergs but the ice charts we had sailed with were over a week old. We needed an update.
标签: Interference Analysis
上传时间: 2020-05-27
上传用户:shancjb
At the macroscopic level of system layout, the most important issue is path loss. In the older mobile radio systems that are limited by receiver noise, path loss determines SNR and the maximum coverage area. In cellular systems, where the limiting factor is cochannel interference, path loss determines the degree to which transmitters in different cells interfere with each other, and therefore the minimum separation before channels can be reused.
标签: Characteristics Channel Mobile
上传时间: 2020-05-30
上传用户:shancjb
This book is about multipoint cooperative communication, a key technology to overcome the long-standing problem of limited transmission rate caused by inter- point interference. However, the multipoint cooperative communication is not an isolated technology. Instead, it covers a vast range of research areas such as the multiple-input multiple-outputsystem, the relay network, channel state information issues, inter-point radio resource management operations, coordinated or joint transmissions, etc. We suppose that any attempt trying to thoroughly analyze the multipoint cooperative communication technology might end up working on a cyclopedia for modern communication systems and easily get lost in discussing all kinds of cooperative communication schemes as well as the associated models and their variations.
标签: Communication Multi-point Cooperative Systems
上传时间: 2020-05-31
上传用户:shancjb
Optical wireless communication is an emerging and dynamic research and development area that has generated a vast number of interesting solutions to very complicated communication challenges. For example, high data rate, high capacity and minimum interference links for short-range communication for inter-building communication, computer-to-computer communication, or sensor networks. At the opposite extreme is a long-range link in the order of millions of kilometers in the new mission to Mars and other solar system planets.
标签: Communication Wireless Optical Systems
上传时间: 2020-05-31
上传用户:shancjb