fading method 中文意思是什麼
-
Stbc ( space time block code ) is the main method to realize mimo diversity, and it is good at mitigating the influence of wireless multipath fading
而stbc （ spacetimeblockcode ，空時分組碼）則是實現mimo分集的重要手段，長于對抗通道的多徑衰落。 -
And the impact of processing conditions on the electrochemical performance of the porous sn - cu alloys was investigated. results showed that it was good to add more verdigris and to make the annealing time longer for improving the performance. however, the problem of capacity fading can not be solved completely by this method
並對制備合金材料過程中所添加物質的種類和比例、燒結時間等工藝參數對合金的性能的影響進行了分析，發現添加堿式碳酸銅，並且增大添加比例以及延長燒結時間對電極材料的循環壽命有利，但是不能根本解決容量衰減的問題。 -
Turbo codes represent the new code structures, which consist of pccc ( parallel serially convolutional code ) and sccc ( serially concatenated convolutional code ). in this paper, the background of turbo codes are firstly introduced, which includes the base principle of error correction code 、 block code and convolutional code ; the principle of turbo code and the iterative decoding is secondly expanded ; the key decoding algorithm : a revised map algorithm and iterative decoding theory are detailed ; then, a new turbo code structure : hccc ( hybrid concatenated convolutional code ) is presented, and the capacity of this code method is analyzed, the average capacity upper bound is derived ; at last, this code is simulated on awgn ( additive white gaussian noise ) channel and rayleigh fading channel
本文首先介紹了turbo碼的背景知識，包括差錯控制的基本原理、分組碼和卷積碼；然後闡述了turbo碼的基本原理，包括turbo編譯碼器結構及迭代譯碼原理；較為詳細地描述了關鍵的譯碼演算法： ?種改進的最大后驗概率（ map ）譯碼演算法及迭代譯碼演算法；提出了一種新的turbo碼結構：混合turbo碼（混合級聯卷積碼） ；並用編碼性能聯合界分析方法對混合turbo碼進行了性能分析，得出了其平均性能上界；並在高斯白噪聲通道和瑞利衰落通道上分別作了一些應用研究及計算機模擬實驗。 -
The simplified gaussian approximation can be obtained, which has almost the same in accuracy but much less calculations than improved gaussian approximation method. the single traffic cdma system in nakagami fading channel with rake receiver is investigated extensively. a closed form ber expression is obtained with arbitrary chip waveforms
由於在用戶小時其誤差大，改進高斯法可以提高精度，但需要更多的計算時間，少用戶時直擴系統的工程計演算法能夠獲得與改進高斯法相似的精度，但需要的運算量大為減少。 -
The basic idea of this method is to produce particles from the posterior densities, and these weighted samples provide approximations to the densities. in this dissertation, sequential monte carlo method and its applications in communication are investigated. firstly, its basic idea, method and improved method are introduced, then induce the bound of particles, which determines the performance of the system, and the more particles are chosen, the higher computation is done, finally, a new detector based on new importance function is proposed, which deals with the joint channel estimation and detection in flat fading channels
首先介紹了它的基本思想、基本方法、及當前研究現狀；在此基礎上推導出樣本數選擇的界，樣本數的選擇決定了系統的性能，但是若選的太多，計算復雜度也會隨之增大，因而給出這個界是十分有意義的；最後提出了一種基於新的重要函數的檢測器用來解決平坦衰落通道下的聯合通道估計和檢測問題，並通過模擬證明了我們提出的新檢測器的有效性。 -
Lt is well anown that the multi ? ath effeet results in signal fading and intersymbol interference ( isd, wnich causes great difficulhes in pewces of transndssion in underwater acoushc cotnmnication. in this papef we used frequency diversity method to overcome the problem of signal fading, and used the frequency - hopping method to ebonate the isi caused by multi - path
水聲通道多途特性引起的信號衰落和碼間干擾是影響水下通信質量的主要因素，採用頻率分集技術可以處理幅度衰落，而跳頻技術則可以簡單、有效地抗多途引起的碼間干擾。 -
As the step of the color tv ( the second generation ) to the digital tv ( the third generation ) is larger and larger, the research of digital television terrestrial broadcasting ( dttb ) become more and more important in china, we are concentrating on the standard of dttb which is suit for our country after describing and analyzing the technical stipulation and speciality of dttb, this paper compares atsc 8 - vsb with dvb - t cofdm and isdb - t bst - ofdmo the emphasis of this article lies in the technical solution about transferring system, channel coding is important component of dttb, which can resist from the bad circumstances o because of lots of varieties and different performance, channel coding become one of the emphasis of the research work this paper analyzes and researches the theory and performance of the different channel coding particularly, points out an effective theoretic analysis method and computer demo of performance comparison a theoretical method for estimating the performance of concatenated codes is proposed in this paperc this is achieved by combining the performance of single level coding rayleigh fading channel and the character of channel modulation it may be useful to research and development of the future digital television terrestrial broadcasting standard of our country
通道糾錯編碼是數字電視地面廣播傳輸系統的重要組成部分，是抵禦地面惡劣環境的有效手段。由於通道編碼的種類繁多，性能各異，因此是目前研究工作的重點之一。本文詳細分析和研究了幾種通道糾錯編碼的原理和性能，並針對外碼內碼級聯糾錯結合地面通道瑞利衰落提出了一種有效的理論分析方法和性能的計算機比較演示方案，總結了不同級聯方案的性能特點，對於我國目前的數字電視地面廣播標準的研究和通道級聯糾錯方案的確立及其參數選擇具有一定的參考價值。 -
The paper proposes a feedback pre - equalization ( f - pe ) method based on channel estimation in a frequency - selective rayleigh fading channel
在頻率選擇性瑞利衰落通道條件下，提出一種基於通道估計的反饋?預補償均衡檢測演算法。 -
Appropriate data compression methods are needed to assure the random nature of the information source and to enlarge its entropy. in this thesis, first, we present the theory of sess system, then the acquisition method of sess system is discussed in detail, finally, a acquisition model of sess system is built and simulated in the awgn channel, in the raleigh fading channel and in multi - address interfere condition. the simulation results show the acquisition method of sess system can be just as reliable as the conventional dsss systems
本文首先對自編碼擴頻通信的基本原理，自編碼擴頻序列的產生方法及其產生的序列的特性進行了概述，然後詳細討論了直擴通信系統中的擴頻碼的捕獲跟蹤問題，根據自編碼擴頻通信的特點，設計了其捕獲跟蹤方案，並在加性高斯白噪聲通道、瑞利衰落通道和多址干擾情況下進行了模擬。 -
There are two main factors resulting in fading capacity and poor cyclability, one is the john - teller distortion of mn3 +, and the other is mn dissolution to electrolyte. the main objects of this paper are to resolved these key problems effecting on the performance of batteries. during the research of suppressing jahn - teller distortion, low valence cation ( al 、 mg ) and anion ( f ) doped method are usually adopted
針對limn2o4正極材料在電化學循環過程中發生jahn - teller畸變和mn在電解液中溶解這兩個導致容量衰減和循環性能劣化的關鍵問題，分別採用al 、 mg陽離子摻雜和al / f 、 mg / f陰陽離子復合摻雜兩種措施，對尖晶石結構limn2o4正極材料進行了改性研究。 -
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。 -
3 a novel recursive least - square ( rls ) blind space - time receiver algorithm based on the constrained condition, which can completely avoid the matrix inversion introduced into by constraints ( comparing with the normal rls ), is proposed for multi - path slow fading cdma channels. the computational complexity of this method is not only lower than that of the normal rls, but also lower than that of both lms and ls blind space - time receiver methods that are realized based on the rosen ' s gradient projection. and the speed of convergence of the presented rls blind space - time receiver algorithm is better than that of both lms and ls blind space - time receiver methods
3 、針對多徑慢衰落通道下ds - cdma盲空時接收機中線性約束二次規劃問題提出一種新的遞歸最小二乘演算法，該演算法完全避免因約束而引進的矩陣求逆運算（相對于常規的遞歸最小二乘演算法） ，不但運算量比常規的要低，而且比基於rosen梯度投影實現的最小均方（ lms ）與最小二乘盲空時接收機演算法還低，且收斂速度比基於rosen梯度投影實現的最小均方（ lms ）與最小二乘盲空時多用戶檢測都好，將提出的新的遞歸最小二乘演算法與提出的數據選擇方案結合起來可以進一步降低其運算量，具有很大的實用價值，最後通過模擬實驗進一步分析了其性能。 -
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。 -
The fading correction and its corresponding calculation method were specially introduced in this paper for improving the accuracy of the environment cumulate kerma
為了提高環境累積比釋動能的測量準確度，特別介紹了環境劑量計的衰退修正及其計算方法。 -
This method can convert the dispersive channels into independent flat fading subchannels, so that it increase the diversity gain of the receiver and outperform that of the original paper as for the ber performance and maximum mutual information while maintaining all the advantages of it. in chapter 4, the models of the tv dispersive channels are reviewed in signal processing perspective
在第四章中，作者對時變色散通道的信號處理模型進行了研究，提出了離散正則模型的概念，對其進行了詳細的討論，並利用多采樣率理論將該模型推廣到一般的時變色散通道。 -
It is very difficult to design a high - quality underwater acoustic data transmission system. in our study, we use frequency diversity and frequency - hopped technology. this method is an effective solution for the isi and signal fading
該方法起到保證mfsk傳輸系統使用頻率中文摘要統使雨頻率分集技術能得以有效的實現；並可用於提高mfsk信號檢測精度，因此在頻率信號檢測中它有廣泛應用意義，它是本文重要創新之處。 -
In chapter 3, a based on pilot symbols channel estimation method and its simplifiede method are discussed in detailed. in this chapter we bring forth a method that is fit to the extremely fading channels
第三章介紹了一種基於導引符號的mimo - ofdm系統的通道估計方法及其改進型方法，同時提出了一種適合於極端衰落通道條件下的基於導引符號的通道估計方法。 -
In this thesis we analyze in detail the influence, created by random change of the optical wave polarization, on the output of the interferometer. then several principles of eliminating polarization - induced fading are introduced, and the principle that inserting two faraday rotator mirrors into the end of michelson fiber interferometer to eliminate the fading is analyzed in detail. this method can eliminate polarization - induced fading without additional signal processing, and make the output of the sensor stable
其中，本文詳細分析了光波偏振態的隨機漂移對干涉儀輸出的影響，介紹了目前幾種消偏振衰落技術的原理，著重討論了在光纖michelson干涉儀末端加兩個法拉第旋轉鏡的消偏振衰落的原理，該方法不需要任何附加的信號處理就可以消除偏振衰落，使干涉儀輸出穩定。 -
Considering the disadvantages of these methods in dealing with fast fading channels, a chip - level adaptive channel estimation method is proposed in this thesis and has better performance than other methods. furthermore, a procedure to derive optimum step length for this technique is given in particular
在分別對簡單平均， wmsa和fbprelms通道估計演算法進行分析后，著重介紹了適于低速與高速衰落情況下，進行碼片級自適應變步長lms通道估計的由來、原理與實施的具體方法，並且推導了變步長的選取。 -
In this paper, the low - temperature synthesis method - sol - gel mehtod was used to improve the capacity fading of the cathode with cycling for lithium - ion secondary battery
本文針對鋰錳氧化物循環過程中容量衰減的問題，採用了低溫合成方法即溶膠凝膠法。
分享友人