衰落時間 的英文怎麼說

中文拼音 [shuāilàshíjiān]
衰落時間 英文
decay time
  • 衰 : 衰動詞（衰弱） decline; wane
  • 落 : 落名詞[方言] （北方對蓮花落的俗稱） a kind of folk song
  • 時 : shí］Ⅰ名1 （比較長的一段時間）time; times; days:當時at that time; in those days; 古時 ancient tim...
  • 間 : 間Ⅰ名詞1 （中間） between; among 2 （一定的空間或時間里） with a definite time or space 3 （一間...
  • 衰落 : decline; be on the wane; go downhill; fading; decay; decaying; lapse; erode
  • 時間 : time; hour; 北京時間十九點整19 hours beijing time; 上課時間school hours; 時間與空間 time and spac...
  1. Through textual research and analysis on two historical materials in dao zang ' s shangqing mingjian yaojing and dongxuan lingbao daoshi mingjingfa used for polishing bronze mirrors, this article holds that : china had already mastered the technique of plating a bronze mirror with an alloy of stannum, lead and hydrargyrum during the northern and southern dynasties at latest, and this technique was quite probably developed by necromancers or taoists in the process of producing artificial gold and silver, golden elixir and great elixir ; before the song dynasty, the technique of using the alloy of stannum, lead and hydrargyrum to polish a bronze mirror was only prevalent among a part of taoist alchemists ; and after the song dynasty, due to the decline of taoist laboratory alchemy, the technique of using such an alloy was spread among the people

    摘要通過對收錄于《道藏》之中的《上清明鑒要經》和《洞玄靈寶道士明鏡法》兩部經書所記載的兩則磨鏡藥史料的考證分析，提出至晚在南北朝時期中國已經發明了用錫汞齊鍍鏡的技術，其技術很可能由方士或道士在煉制黃金白銀、金丹大藥的過程中或社會小范圍內發展起來的；在宋代之前，用錫汞齊磨鏡的技術僅僅在部分煉丹道士中應用流傳，宋之後由於道教外丹術的衰落，用錫汞齊磨鏡的技術流傳於民間。
  2. Therefore, during system design, cascade coding combining reed - solomon codes and convolutional codes is utilized ; in addition, time - direction and frequency - direction interleaves are added to alleviate channel fading

    因此在進行系統設計時，採用了rs碼與卷積碼的級聯編碼方案，並同時加入時間交織和頻率交織來對抗通道衰落。
  3. Shortwave channel is time varying transmission channel. it has dispersion in frequency and time domains. this characteristics hinds the data transmi - ssion at high speed and the correction of received data. in this dissertation i have analyzed the statistic characteristic of shortwa - ve channel, established the model of shortwave channel and simulated the rayl eigh fading distribution. the technology of spreading spetrum has been proved that it has the capability for anti - multipath and discerning multipath

    在短波通信中，由於通道的時間色散和頻率色散，引起多徑展寬和多徑衰落，前者限制了數據的傳輸速率，後者造成短波數據通信中出現突發錯誤，為了解決多徑效應對短波通信的影響，本文所做工作如下：首先詳細分析了短波通道的統計特性，建立其數學模型；其次分析了擴頻通信的特點，從理論上證明擴頻技術不僅具有抗多徑干擾能力，而且具有分離多徑的能力；介紹了傳統的rake分集合併技術的特點。
  4. This thesis analyzed the error performance of mfsk and mpsk modulator in hf with optimal receiver, studied the shortcoming and strongpoint of several typical short - wave data transmission systems and their performance over fading and intersymbol interference channels. the theory and key technical of adaptive modem is discussed. in the last, an efficient modulation scheme - block coded modulation is introduced into hf radio systems to improve the efficiency of hf data transmission, this paper also proposes a hf data transmission system scheme composed of a block coded modulator and a decision feedback type adaptive equalizer

    本文在對短波數傳兩種常見調制方式fsk及psk最佳解調性能分析的基礎上，討論了幾種採用典型調制技術的短波數傳系統（如時頻調制、多進制頻移鍵控慢跳頻、 chess系統）原理、優缺點以及抗衰落和抗符號間干擾的性能；分析了自適應串列數傳系統抗短波通道衰落和多徑干擾的原理、關鍵技術；在本文的最後引入一種有望解決短波數傳系統低效率狀況的調制方式bcm -分組編碼調制，給出了一個採用bcm技術與自適應均衡技術相結合的短波數傳系統方案，並通過計算機模擬進行了初部驗證。
  5. 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。
  6. Diversity receiving technique for synchronous time spreading signal in time - varying fading channels

    時變衰落通道中同步時間擴展信號的分集接收技術
  7. Under rayleigh fading channel, we also simulated and compared ber in siso 、 simo and mimo systems. secondly, based on careful study the ber and the channel capacity under white noise channel under mpsk modulation when the channel is rayleigh fading, we duduced the expressions of stbc ’ s ber and channel capacity under rice and nakagami fading. and also analysed the performances through numerical simulation using matlab to testify the exactitude of the dudeced expressions. finally, there exists an error floor of stbc through studying on its performance on time - selectiv fading channel. we analysed the reason and proposed two new decode combination scheme to eliminated the error floor and the performance of stbc on time - selective fading channel is improved. and also compared the two scheme ’ s complication and snr gain

    這些結果大部分是閉式結果，能比較準確地衡量空時塊碼的性能，並對不同衰落的性能做了相互比較，其結果對空時塊碼的實際應用具有一定的指導意義。實際的通道是時變的，分析了空時塊碼在時間選擇性衰落通道中產生誤差地板效應的主要原因是存在碼間干擾（ isi ） ，在此基礎上提出了兩種能消除誤差地板效應的譯碼合併方案，並對這兩種方案的復雜度和信噪比增益進行了比較。
  8. In this dissertation, multiuser detection and space - time processing are combined to suppress multiple access interferences and inter - symbol interferences ( isi ) jointly in multipah fading channels with large delay spread

    本文組合多用戶檢測和空時處理技術，在大時延擴展的多徑衰落通道條件下，研究多址干擾和符號間串擾的聯合抑制。
  9. The new method is a modified pts method, and can make good compromise between performance and computational complexity. the dissertation explores, by means of computer simulation, how the conventional method based on amplitude - limiting and filtering affects the performances of wavelet packet modulation signals, and presents a new method, namely, selective mapping / amplitude limiting / filtering method, which proves to be effective, simple, and have better ber performance

    並基於自子波變換和時間、尺度解析度的概念，從理論和模擬實驗兩方面對通道建模和時間/尺度rake接收機進行了分析，並與傳統的kake接收機進行了比較，結果表明時間/尺度聯合分集能有效地克服高速衰落多徑通道的影響。
  10. The decline of literature indicates the decline of a nation ; the two keep in their downward tendency

    文學的衰落表明一個民族的衰落。這兩者走下坡路的時間是齊頭並進的。
  11. A new approach to equalization of linear single - input single - output time - selective fading channel

    時間選擇性衰落通道迫零均衡新方法
  12. The following algorithms have been proposed and tested in the thesis : 1 frequency selective fading : combine the isomorphism between the input space and the output space and propose a new approach to blind equalization of the channel. compared with conventional methods, the new approach offers lower computational complexity, better performance, and more robust against the over - determination of the system order ; 2 time selective fading : a new approach to the equalization of time selective channel based on the zero - forced equalizer is proposed which is more simple in its structure of algorithm ; 3 time - varying channel : using the instantaneous mean value changes of the output signal to extract the information of channel variations and model it using ar model, kalman filter is then employed to track channel variations, it bears faster ability in tracking the variation of tv channels ; based on the isomorphism between the inputs and the outputs and some of the approaches using in mimo system, a new algorithm of equalization of simo time - varying channel is proposed, which also share the merits of being robust against the over - determination of the system order ; model the time - varying channel using the multi - resolution decomposition wavelets, and then a blind identification method based " on the model is proposed ; at last, a new model for equalization and identification of mimo system is proposed

    主要工作在以下幾個方面： 1 、針對頻率選擇性衰落通道：結合輸入輸出空間同構關系提出一種新的頻率選擇性通道均衡方法，與傳統方法相比，該方法計算量更小，收斂速度更快，性能更優，且對系統階次的過確定表現穩健，具有實際均衡應用價值； 2 、針對時間選擇性衰落通道：提出一種基於迫零均衡的時間選擇性通道均衡方法，演算法結構簡單； 3 、針對時變色散通道：利用瞬態均值曲線提取通道時變信息，對之ar建模，利用卡爾曼濾波器跟蹤時變通道抽頭變化，可以快速跟蹤通道變化；基於輸入輸出空間之間的同構關系以及多輸入多輸出系統的處理方法，提出了新的單輸入多輸出色散時變通道均衡與識別演算法，同樣具有對通道階次過確定保持穩健的優點；結合小波多解析度分析提出一種基於小波模型的通道盲識別演算法；研究時變的多輸入多輸出系統的盲均衡與盲反卷積問題，給出一種時變系統處理模型。
  13. Combined with the data - selected schemes proposed, the computational complexity of this method can be lowered. the performance of the presented rls method is analyzed by simulations, and it is shown that this method is interesting for application. 4 time - selective channel signal model based on multipath - doppler diversity representation is given in multi - path fast fading channel, and rls space - time receiver algorithm based on time - varied constraint condition is presented and the computational complexity of this method is analyzed

    4 、針對多徑快衰落通道下的ds - cdma系統，給出了基於多徑-多譜勒觀點描述的1百安電弓卜科東兔j憶學協士學位論文時間選擇性通道的信號模型，提出了基於變約束條件下的遞歸最小二乘空時接收機演算法並分析演算法的運算量，最後通過模擬分析了所提出的方法的性能。
  14. Then the performance for sttc in multipath and time - dispersive fading channels is derived. in chapter 5, space - time block coding ( stbc ) is studied

    研究了空時格狀編碼在多路徑和時間色散的衰落通道中的性能，得到它的性能限。
  15. But when the bit rate is above 1 mbps, the signal suffers frequency select fading, which causes the serious intersymbol interference ( isi ). increasing the system power can ’ t reduce the ber

    但是當碼速率提高到1mbps以上時，信號受到頻率選擇性衰落，碼間干擾嚴重，增大系統功率也不能降低系統誤碼率。
  16. A time - varying disperse channel is a channel that contain both frequency selective fading and time selective fading

    時變色散通道則是同時存在頻率和時間選擇性衰落的通道。
  17. Because of the different time delay among multi - paths, the received signal undergoes frequency - selective fading

    由於多徑干擾之間具有不同的時間延遲，接收信號將承受頻率選擇性衰落。
  18. ( 3 ) for the wireless channels subject to several types of fading existing in different time scales, the dynamics of channel conditions are decoupled into two random processes with different mathematic properties in different time scales. two algorithms in this scheme are proposed to dealing with each time scale : the resource optimizer allocates the resource to maximize the total revenue with price fairness and provide qos guarantees to applications, and the slot scheduler exploits the time variability of

    （ 3 ）針對無線通道衰落的多時間尺度特性，將通道條件snr分解到不同時間尺度上，在不同時間尺度上針對不同的衰落特性來設計不同的演算法，完成不同的任務：在大時間尺度（幀）上進行資源分配，面向應用提供qos保證，保持應用間price公平性的情況下，尋求系統總收益utility的最大化；在小時間尺度（時隙）上進行時隙調度，利用各用戶通道容量的時變性，使各用戶獲得比平均通道條件情況下更高的吞吐量。
  19. Decay time of sinusoidal oscillation

    正弦振蕩的起伏衰落時間
  20. With the characteristics of large ambient noise, very narrow bandwidth, low carrier frequency, great propagation latency and time - space - frequency variant multipath effect ( mpe ), the stochastic ocean channel has demonstrated the greatest complexity and difficulty for underwater acoustic wireless communications. among them multipath effect ( mpe ) is the most difficult obstacle that results in signal fading and inter - symbol interference ( isi )

    但是噪聲高、帶寬窄、載波頻率低、傳輸時延大、多途徑效應隨時間?空間?頻率變化等通道特性都會給有效、可靠的水聲通信帶來很大的麻煩，其中多途徑效應是最主要的困擾因素，它會導致信號幅度衰落和碼間干擾。
分享友人
分享到 Line

分享到臉書