載頻恢復 的英文怎麼說
中文拼音 [zǎibīnhuīfù]
載頻恢復
英文
carrier reinsertion-
As a result, pseudorandom code acquisition and tracking, carrier recovering, error correction and decoding functions are needed in the if digital receiver
因此，其中頻數字接收機需要完成偽隨機碼捕獲跟蹤、載波恢復、糾錯譯碼等功能。In this paper, chroma dc coefficients are selected as the carrier data because chroma dc coefficients are robust. also, alterable steps are used to select one part of the coefficients, so the watermark is imperceptible ; before watermark embedding, the watermark is divided into many parts, every part is individually embedded into one gop of the video, even if a gop is destroyed, the watermark can be extracted correctly, this methods promotes the robustness of the watermark ; in addition, in order to promote the security of the watermark, the user ' s id and password are used to generate chaos sequence by the chaos system which is created in this paper, later, watermark is mixed by the chaos sequence. also, the embedding position of the watermark bit is modified by one chaos sequence, so, unauthorized person can not extract or remove the watermark, since the embedding position is unknown
本文認為，色度dc系數是魯棒性非常好的參數，因而選擇色度dc系數作為水印信息載體，同時，採用可變的步長選擇部分系數，保證了水印的隱形性；在嵌入水印時，本文採用水印信息「網格劃分」 、各子塊獨立嵌入視頻的方案，由於水印信息子塊是相對獨立的嵌入視頻中的每一相對獨立的圖組當中，即使某一圖組收到一定破壞，也能夠恢復水印信息，使水印的健壯性得到提高；此外，為了提高水印信息的安全性，在嵌入水印信息時，根據用戶輸入的id號和密碼，利用本文構造的混沌系統產生的混沌序列對水印信息進行變換，同時，對每一水印信息比特的嵌入位置也採用了偽隨機序列進行調整，這樣，未授權用戶不能提取水印信息，也難以擦除其中的水印信息，因為嵌入的位置是未知的。The digital base - band cdma transmitting and receiving scheme is put forward. the scheme uses a technique called as zero medium frequency without the need of pn codes synchronously are resumed
提出了具有免偽碼同步恢復、免載波同步提取、免位同步的零中頻cdma數字基帶發送、接收方案。It is necessary in digital communication system that carrier recovery can compensate frequency offset and phase jitter brought by transmission and modulation. this paper is mainly focused on carrier recovery technique. we introduce the channel model at cable headed and receiving site. firstly, we introduce the principle of carrier recovery and give some algorithms of them, which are directed - decision, reduced constellation and frequency sweeping
本論文緊緊圍繞著數字通信系統中的載波恢復技術，在介紹了有線通信系統所用的調制解調通道模型后，首先闡述了載波恢復技術的思想和基本原理，在此基礎上給出了三種載波恢復演算法，即判決導向演算法、簡化星座判決演算法和掃頻演算法，並且給出了其各自的模擬圖：然後深入研究了一種適合高階qam並且能糾正較大頻偏的載波恢復技術：極性判決演算法。Secondly after damage model of structure is analyzed and considering of rigid degradation in crossing section of structure, the damage index is defined by rotation rigid of element side and the model of damage of crossing section is developed. meantime, the damage model of structure is built by idea that damage index of elements endowed weight are added linearly
其次，在對現有的結構損傷模型分析之後，考慮到構件截面恢復力模型中卸載剛度的退化現象，作者基於構件端部截面的轉動剛度定義了構件的損傷指標，建立了構件層次上的損傷模型。同時考慮到結構損傷前後固有頻率的變化，運用線性加權求和的思想建立了結構層次上的損傷模型。For carrier synchronization, a method of estimating the ofiset of carrier frequency has been presented, which has a more broad range of the estimated oflset of carrier fiequency and more accurate result man other methods, then, a method of estimating the carrier complex phase has been presented, which corrects directly the ofiset of carrier phase
對于全數字接收機中的載波恢復，先提出了一種估計范圍寬、估值精度高的載波頻偏估計演算法，接著介紹了一種可以直接對載波相位偏差進行補償的復相位估計方法。Then time domain synchronization including symbol, frequency and carrier synchronization algorithms is discussed according to the characteristics of frame structure in merged scheme. at the same time, pointed out its merit that high rate of spectrum utilized and rapid synchronization retrieved. and simulation and much improvement are done to realize the algorithms in project
然後根據融合方案的幀結構的特點，分析和探討了時域同步演算法，包括符號同步、載波頻率同步和采樣同步演算法原理，指出時域同步有頻譜利用率高，同步恢復快等優點，並對其進行了工程可實現的改進和模擬。This thesis deals with the synchronization technologies for all digital receiver, particularly carrier offset estimation for mpsk signal
本文研究全數字接收機中的同步技術，重點是mpsk信號的載波頻偏和相位誤差的估計和恢復演算法。In chapter 1, the basic principle and structure of the integrated anti - interference data transmission system are introduced. in chapter 2, the theory of maximum likelihood ( ml ) carrier synchronization parameter estimation ( frequency estimation and phase estimation ) are expatiated, and the closed - loop recovery methods ( phase - locked loop, pll ) and some other arithmetic in common use are introduced
第二章對最大似然（ ml ）載波同步參數估計（頻率估計和相位估計）理論進行了闡述，對常用的閉環恢復法即鎖相環（ pll ）法和一些載波同步參數處理方法進行了介紹，並對常用的載波頻率估計方法作了分析比較。分享友人