碼分多址通道 的英文怎麼說

中文拼音 [mǎfēnduōzhǐtōngdào]
碼分多址通道 英文
cdma channel
  • 碼 : Ⅰ名詞（表示數目的符號或用具） a sign or object indicating number; code Ⅱ量詞1 （指一件事或一類的...
  • 分 : 分Ⅰ名詞1. （成分） component 2. （職責和權利的限度） what is within one's duty or rights Ⅱ同 「份」Ⅲ動詞[書面語] （料想） judge
  • 址 : 名詞（建築物的位置; 地基） location; site; ground; foundation
  • 通 : 通量詞（用於動作）
  • 道 : Ⅰ名詞（道路） road; way; route; path 2 （水流通過的途徑） channel; course 3 （方向; 方法; 道理） ...
  • 通道 : thoroughfare; passageway; pass; enterclose; gallery; drong; tunnel; avenue; alure; way; row; key ...
  1. In this paper, after introduction of the code division multiple access ( cdma ) and orthogonal multicarrier ( mc ) technique, the system model of mc - cdma is analyzed and the bit error rate ( ber ) performance in downlink and uplink channel is shown in awgn channel by computer simulation

    本文在碼分多址技術和正交多載波技術原理基礎上，分析了高斯白噪聲通道中多載波碼分多址（ mc - cdma ）系統的數學模型，並且使用不同的擴展碼對下行通道和上行通道誤碼率性能分別作了計算機模擬分析。
  2. Traditional multiuser detector make good use of all signals which resuilt in multiple access interference so that it provides optimum mai resistance. ( 1 ) nevertheless, it assumes that the receiver can acquire the signature waveform and timing of desired user and the interfering users ; ( 2 ) it has no ability to suppress intercell multiple access interference ; ( 3 ) it cannot be applied in downlink channels. adaptive multiuser detector eliminates the need to know the signature waveforms and the timing of the interferes and has to need training data sequences for every active user

    傳統多用戶檢測在單用戶檢測技術基礎上，充分利用造成多址干擾的所有用戶的信息進行聯合檢測，從而具有良好的抗多址干擾能力，但存在一些缺陷： （ 1 ）不僅要求知道期望用戶的地址pn碼及其定時信息，還要求其他干擾用戶的地址pn碼及其定時信息； （ 2 ）不能消除其他相鄰小區的多址干擾對本小區的影響； （ 3 ）不能直接應用在cdma移動通信系統中的下行鏈路。
  3. In this thesis, first, we present the theory of sess system, the generation of the sess spreading code and its characteristics and the acquisition theory of conventional spread spectrum communication system. an efficient acquisition scheme based on periodically transmitting the synchronization head, which is composed of binary chaotic codes, using the matched filter and automatic decision threshold - level control based on a so - called constant false alarm criterion for sess system is present. the acquisition model of sess system is built and simulated in the awgn channel, the raleigh fading channel and imulti - address interfere condition

    本文首先概述了自編碼擴頻通信的原理、自編碼擴頻序列的產生方法及其特性和擴頻通信系統編碼同步的理論，然後針對自編碼擴頻通信系統提出了擴頻序列捕獲方案:周期性地加入混沌序列同步碼，並採用恆虛警率匹配濾波器捕獲法;在加性白高斯噪聲通道、瑞利衰落通道和多址干擾情況下進行了模擬，分析了各種捕獲性能:在選擇性能最優的混沌序列、適當的序列長度、虛警概率及門限值的情況下，可以獲得較短的捕獲時間和較大的捕獲概率。
  4. Uplink space - time channel blind estimation for space - time coded multicarrier code division multiple access systems

    空時編碼多載波碼分多址系統上行空時通道盲估計
  5. With the trend that cdma will be the dominant multi - access scheme in the new generation of wireless communication, how to apply spatial processing in cdma system has been becoming the emphasis of research in smart antenna. a proper method is space - time processing due to the space - time structure of wireless channel. beamforming can be combined with rake to form 2d rake receiver, which can effectively weaken the enhancement of mai in conventional rake receiver. however a more effective method is to use space - time filtering. these two scheme will be discussed and the structure and realization will be presented

    碼分多址技術逐漸成為新一代通信系統的主流多址技術，如何在碼分多址系統中引入空域處理以改善系統性能是當前智能天線技術研究的重點之一.考慮到無線通道的時空二維結構特徵，一種合理的實現方式是採用時空處理方法，將波束形成技術與時域分集技術相結合;另一種更有效的方法是在接收端採用時空二維聯合處理，對無線通道進行時空二維均衡
  6. Code division multiple access ( cdma ) communications systems being possessed of the merits of great capacity and soft hand - off and so on must have taken a significant role in future wireless communications systems. because pn sequences used in communications systems are been vertical completely, when numbers of user are more, there are multiple access interference ( mai ) in cdma and serving quality in communications systems is reduced

    碼分多址（ cdma ）通信系統以頻譜利用率高、系統容量大、頻率管理容易，軟切換、移動臺發射功率低、通道的傳輸速率高等優點代表了新一代移動通信，在未來的無線通信系統中必將扮演極為重要的角色。
  7. Conventional detector ( single - user matched filter ) distinguishes each user by the crosscorrelation of their spread - spectrum codes. in practice, however, its performance is much deteriorated due to the existence of noise in channel and strong multi - access interference, i. e. near for effect. a new method using independent component analysis is proposed in this paper. the - received energy of signals is controlled effectively, thus the near - far effect is overcome as much as possible ; moreover, the effect that noise imposed on the detector is mostly reduced. simulations verify the effectiveness of this method

    傳統檢測器（單用戶匹配濾波）利用擴頻碼之間的互相關特性來區分各用戶信號.而在實際應用中，通道噪聲和近距離用戶對遠距離用戶的強多址干擾即遠近效應，使得接收機的性能受到很大影響.本文將獨立分量分析法引入傳統接收機，有效控制接收信號的能量，從而極大地提高了接收機的抗遠近性能，同時噪聲的影響被盡可能消除.模擬結果表明了該方法的有效性和可行性
  8. Proposes a novel channel estimation algorithm for multi - carrier code division multiplex access ( mc - cdma ) systems on the uplink

    摘要提出了一種新穎的適用於多載波碼分多址接入（ mc - cdma ）系統上行鏈路的通道估計演算法。
  9. It inherits the anti - multipath fading ability of ofdm technology as well as the high user capacity of cdma. however, the ofdm - cdma system is vulnerable to channel estimation errors in fast varying channels

    但是在快速時變通道中，正交頻分復用碼分多址系統對于通道估計誤差很敏感。
  10. Abstract : analyzes the performance of unipolar ocdma system using optical orthogonal code ( ooc ) considering the dispersion and nonlinearity effect of the transmission medium. theoretical analysis demonstrates that dispersion and nonlinearity effect deteriorate the system performance. the performance of ocdma system assuming dispersion - shifted fiber as transmission medium is very close to the case neglecting the dispersion and nonlinearity effect. assuming rz initial pulse and optical hard limiter are also possible solutions

    文摘:分析了基於光正交碼（ ooc ）的光碼分多址系統的性能.數值結果表明：與以前忽略光纖通道對系統性能的情況相比，在考慮了光纖的色散和非線性效應以後，系統性能有了明顯的下降.給出了一些建議方案來遏制由色散和非線性效應引起的系統性能惡化
  11. With the downlink simulation model constructed, performance of wideband cdma under different radio propagation environment and vehicular speed is simulated. based on system model of mc ds cdma under flat fading channel with relative shifts of spreading sequences within 1 chip and frequency selective fading channel with arbitrary relative chip shifts, performance of multicarrier cdma system with go sequences under different radio environment is investigated

    基於多載波直接序列碼分多址在乎坦衰落通道中序列偏移小於1個碼片及在頻率選擇性衰落通道中偏移任意個碼片的系統模型，本文還分析了採用廣義正交序列的多載波碼分多址系統在不同無線傳播環境下的性能。
  12. Optical code division multiple access ( ocdma ) is a communication mode which introduces the code division multiple access ( cdma ) technology into optical fiber communication system. besides providing asynchronous communications access, ocdma system has many advantages, such as high capacity, security against interception, suppression of narrow band disturbances, capability in forming variable bit rate networks and multi - rate networks. it implies a great challenge for the development of future communication networks, especially all optical networks

    光碼分多址（ ocdma ）是將碼分多址（ cdma ）技術與大容量的光纖通信技術相結合的一種通信方式，其主要優點表現在如下幾個方面：允許多個用戶隨機地接入同一通道：可構成真正「透明」的全光通信網路；具有良好的安全性；允許可變速率或多速率傳輸，並可同時提供多種業務支持；具有優良好的抗干擾能力，並能夠充分地利用石英光纖的可用帶寬。
  13. Assigning serial different address code to different subscribers, useful signal is taken out of the same time slot and frequence, and is transmitted with one share channel. at received end, system makes use of completed address code from sending end to do correlative check and take out useful subscriber signal. the other address code signals are treated as broadband disturbing signal which is removed. in radio environment of existing variable disturbtion and muti - way declining, expand frequence signal ’ s broadband characteristics can improve system performance obviously. cdma mobile telecommunication system has some better characteristics, such as anti - disturbing 、 anti - way declining 、 secrecy 、 capacity 、 utilizing rate of frequence resource and so on, than other mobile telecommunication system

    Cdma （ codedivisionmultipleaccess ）移動通信系統的技術基礎是基於擴頻技術的碼分多址，通過給不同的用戶分配各自特定的地址碼序列，將處于相同時隙和頻率的用戶信號分離開來，採用共享通道方式傳輸信息。在接收端，系統利用與發送端完全一致的本地地址碼對接收信號進行相關檢測，提取需要的用戶信號，而將其他使用不同碼型的信號視為寬帶干擾而從中剔除掉。
  14. For power control of listening users, forward power control method are introduced based on full, multichannel, filtered report, and collision method etc. the full report method has redundancy report information, and its real - time performance is bad, multichannel report is introduced to improve the real - time performance, and filtered report is introduced to eliminate the redundancy information, finally the collision method introduced can not only get higher real - time performance but also diminish the redundancy information ; 2. in order to meet the requirements of making the dynamic simulation of trunking group system, the ms ’ s random move equation is brought forward, the simulation of ms ’ s distribution is done and the integrated channel model are presented ; 3. the smart predicative model of power control is introduced to overcome the delay and track the change of the complicated network, with this model, the power control ‘ s performance is greatly improved

    全匯報方法存在冗餘的匯報信息，而且實時性較差，為了改善實時性提出了多通道的匯報方式，為了改善冗餘匯報而提出了篩選法，最後介紹的碰撞法在減少冗餘信息的同時又提高了實時性;二、為了集群功率控制動態模擬的需要，提出了移動臺的隨機運動方程，進行了有關移動臺的分佈模擬，建立了綜合的通道模型;三、希望克服延時和跟蹤復雜網路環境變化，提出了功率控制的智能預測模型，通過智能預測模型可以改善功率控制的性能，著重介紹了採用神經網路的方法實現智能預測的通用模型，從而跟蹤復雜多變的無線環境，諸如慢衰落及快衰落（包括多徑衰落、多普勒效應所引起的衰落）等網路特徵，達到預測功率需求;四、採用二級正交碼和智能天線（空分多址）的方法進行組內用戶的識別，改進功率控制效果;五、話權用戶的前向和反向功率控制方法;六、對引入gota的cdma系統提出了復合容量表示方法，並作容量分析，探討有關gota系統的qos問題。
  15. The problem of signal processing for direct - sequence code - division - multiple - access ( ds - cdma ) signal over multipath frequency - selective mobile channels is considered. a new blind receiver is proposed. without the knowledge of the multiple - access interference users spreading code and the channel characteristics, the receiver achieves blind detection with prior knowledge of only the desired users spreading code and approximate timing. by using reduced rank adaptive decorrelating filter and adaptive multipath combiner which is based on decision - directed algorithm, the receiver gets the ability to combat both fading and the near - far effect at low cost. simulation results demonstrate that the proposed receiver offers high performance

    本文研究多徑頻率選擇性衰落通道下直接序列擴頻碼分多址（ ds - cdma ）信號的處理問題，提出了一種新型的盲接收機.該接收機不需預知多址干擾用戶的擴頻碼，不需預知通道參數，只需已知期望用戶的擴頻碼和粗略的定時，就可以完成用戶的盲檢測.同時，該接收機通過降維自適應去相關濾波和基於判決指導的自適應多徑合併，來獲得低成本和良好的抗衰落、抗遠近效應性能.模擬結果驗證了本文提出的接收機的優良性能
  16. Concerning with the direct sequence ( ds ) cdma system, this thesis focuses on several issues related to orthogonal spreading sequences and amc, including correlation properties of orthogonal variable - length spreading sequences and their effects on ds cdma system performance, performance of multicarrier ( mc ) ds cdma system with generalized orthogonal ( go ) sequences, adaptive modulation with throughput maximization, performance of adaptive turbo - qam coded modulation in generalized fading channel and performance of amc in wcdma high speed downlink packet access ( hsdpa )

    針對直接序列碼分多址（ dscdma ）系統，本文主要研究了正交擴頻序列和自適應調制編碼若干問題，包括正交變長擴頻序列的相關性及其對dscdma系統性能的影響、採用廣義正交（ go ）序列的多載波直接序列碼分多址（ mcdscdma ）系統性能、吞吐量最大化自適應調制、自適應turbo - qam編碼調制在廣義衰落通道中的性能，以及wcdma下行分組接入（ hsdpa ）中自適應調制與編碼性能五個方面。
  17. This dissertation researches on wavelet theory applied to information transmission, including cdma spreading code design, waveform coding in digital modulation, over - saturated multi - access communication, diversity techniques for multi - path fading channels, and peak - to - average power ratio ( papr ) reducing methods for the wavelet packet modulation signals, etc.

    本文以子波理論為工具，較深入地研究了通道傳輸方面的幾個問題，內容包括cdma擴展碼的設計、數字基帶波形成形技術、過飽和多址通信、克服衰落的分集技術和減小子波包調制信號的峰值功率/平均功率比值的方法等。
分享友人
分享到 Line

分享到臉書