spreading sequence 中文意思是什麼
spreading sequence
解釋
擴頻序列-
After establishing the model of intermediate frequency direct sequence spreading spectrum ( if dsss ) receiver, comparing and analyzing several conventional code acquisition methods, code and carrier two - dimension fast acquisition scheme based on two - dimension fft is proposed. finally, the situation for two targets is analyzed
首先在建立了中頻直擴接收機的模型之後，本文對常用的偽碼捕獲方法進行了詳細地分析和比較，然後提出了本文的基於二維傅立葉變換技術的快速捕獲方法，並且分析了兩個目標時的情況。 -
This implies that the cross correlation between the spreading sequence of the user of interest and the signal from a strong interfere can be larger than the correlation with the signal from the desired user
深入分析自然免疫現象的內在動因，優化和完善現有演算法的模型與結構體系，拓展應用領域將是我們下一步研究的重點和努力的方向。 -
3. we propose a new spreading sequence design scheme. in the uplink, using golay sequence, cinew sequence or zadoff - chu sequence, in the downlink, using wh sequence as the spreading sequence, we can control the papr of mc - cdma below 7db and ber below le - 3 ( snr = 20db )
提出mc - cdma中擴頻序列的新型設計方案，在上行通道，採用golay序列， cinew序列或zadoff - chu序列，在下行通道，採用wh序列作為擴頻序列可以控制mc - cdma峰平比在7db以內，在信噪比為20db時，系統誤碼率小於1e - 3 。 -
Cell adhesion to surface of the substrate is essential to development of the anchorage - dependent cells. only after adhering to surface followed by spreading can cells develop and proliferate. most synthetic polymers used as orthopaedic matrix substitute present hydrophobicity, which may correlates to the low degree of cell attachment. modification with cell adhesion protein / peptides can be benificial to the cell adhesion on polymers and then affect the cell proliferation and differentiation. cell attachment to substrate is primarily mediated by integrins, a widely expressed family of heterodimeric surface receptors. most extrcellular matrix proteins such as fibronectin, osteopontin, collagen type i, bone sialoprotein and vitronectin contain an arg - gly - asp ( rgd ) sequence which is specific to the fixation of cell membrane receptors like integrin. the main aim of this research is to measure, assess adhesion, proliferation of rabbit marrow stromal cells ( mscs ) on the polymers coated by fibronectin, collagen type i or biotie gen, which includes : ( 1 ) biologic characteristics of rabbit mscs were observed by two types of separating method in primary culture. ( 2 ) adhesion, proliferation and differentiation of mscs cultured on polymers coated with biotiegen were assessed. ( 3 ) also, adhesion, proliferation and differentiation of mscs were assessed on plga film or porous plga substrates coated with fibronectin, or collagen type i respectively. ( 4 ) bone formation was observed on the porous plga substrates coated with collagen type i in vivo. this research aims to give new way to make novel synthetic bone with cell adhesion and high bone induction capabilities
因此將這些蛋白包被、固定到材料表面，觀察骨組織工程種子細胞mscs細胞的粘附、生長特性是本研究的中心環節，並從以下方面進行探討： （ 1 ）採用不同原代細胞分離方法，研究其對mscs細胞的生物學特性影響。 （ 2 ）檢測基因勝肽膠對mscs細胞粘附、增殖及分化的影響。 （ 3 ）分別採用型膠原及纖維粘連蛋白（ fibronectin ， fn ）包被聚乙醇酸-乳酸共聚物（ poly （ 1actide - co - glycolide ） ， plga ）膜及多孔塊型plga材料，觀察細胞在單層或三維培養狀態下，型膠原及fn對mscs細胞粘附、增殖及向成骨細胞分化效應及能力。 -
At 1999, lim nguyen first brought forward a novel self - encoded spread spectrum ( sess ) system, which spread spectrum sequence is full builded by the source data. in sess system, which does not use pn codes. it employs random spreading sequences that are extracted from the information data
自編碼直擴通信是limnguyen在1999年首次提出的一種利用信源數據產生擴頻序列的隨機直擴技術，它產生具有隨機的、動態可變的擴頻序列，因而是一種較好的安全通信方式。 -
This dissertation analyses the design idea and method for the direct spreading sequence msk modulate system with an error control function. it gives the matlab simulate result and the performance analysis through the modeling process
本文闡述和分析了一個帶有差錯控制的直擴序列msk調制系統的設計原理與方法，詳細分析和推導了系統的建模過程並給出基於matlab的模擬結果與性能分析。 -
Traditional spread spectrum communication adopts pseudo - noise ( pn ) codes as spreading codes. however, pn sequence is fixed and periodic, which threatens the transmission security. self - encoded spread spectrum ( sess ) employs random spreading sequences that are extracted from the random information data, abandoning the fixed sequence
傳統的擴頻通信廣泛採用偽噪聲（ pseudo - noise ， pn ）序列作為擴頻序列， pn序列具有類噪聲特性，但它實際上是確定的周期序列，容易被復制。 -
When we carry through the theoretic analysis, according to the request of cdma communication system for spreading code, we analyze the characteristics of chaotic spreading sequence
在進行理論分析時，根據碼分多址通信系統對擴頻碼的要求，分析了混沌數字擴頻序列的特性。 -
2. on simulating events ’ sequential - quality, we gave an idea of “ batch ” ; instead of conforming to events ’ physical time precisely, we consider about their logical sequence. we proposed an events simulation method based on the idea “ batch ”, considering spreading quality of events and time - mapping logic simulating methods
2 .對于繼電控制系統中事件時序的把握，我們沒有拘泥於其物理上的時間次序，而是從邏輯上來考慮事件的先後相繼關系，提出了邏輯清晰的「批」概念。 -
Based on the single cycle detector, the finite cycle detector is proposed for the detection of phase - coded signals. the finite cycle detector has a good performance under unknown the spreading code sequence, initial phase, spreading code timing epoch
針對相位編碼信號的檢測，提出了基於單循環檢測器的有限多循環檢測器，可在沒有編碼序列、初相、編碼序列初始時間等信息的情況下，取得理想的檢測效果。 -
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 -
Performance of balance base on chebyshev 2 - phasc chaotis spreading sequence
二相混沌擴頻序列平衡性 -
Through analyzing decision variable of receiver, the f - pe method can increase autocorrelation of desire user ' s spreading sequence, and improve the ber performance
對接收機判決變量輸出分析表明，該演算法能有效增加關心用戶的解擴濾波相關峰值，對誤碼率性能有很好的改善。 -
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。 -
But they have the disadvantages such as poor complexity, poor security and insufficient amount of sequence numbers among the family of codes, the chaotic signals have noise ? ike, broadband frequency spectrum, they can be used as spreading codes, furthermore, chaos system is extremely sensitive on initial conditions so that the various initial conditions given by chaos system can provide with large sum of spreading sequences and this can meet the demand of cdma, this thesis sets out to study on using chaos system to generate spreading sequence s, there are two parts is this paper : firstly, we study the basic theory of spread ? pectrum communication and the characteristics of chaos so as to prove the applicability of chaos system to be used in spread ? pectrum ii communication system
現在使用的擴頻碼有m序列， gold碼和r - s碼等，這些擴頻碼具有良好的隨機性，但普遍存在著復雜度低、保密性差以及同一碼族序列數目少等缺點。混沌信號具有類似噪聲、寬帶連續頻譜的特徵，正符合擴頻通信中對擴頻碼的要求，而且混沌系統對初始值極其敏感，可以通過給混沌系統賦予不同的初始值得到為數眾多、不相關的擴頻序列，這正好滿足碼分多址的要求。本文對利用混沌系統應用於擴頻通信作了一些研究工作，主要包括兩部分：第一部分：探討了擴頻通信的基本理論和混沌的基本特性，說明將混沌系統應用於擴頻通信系統的可行性。 -
So the chaotic sequence can indeed serve as spreading address code in spreading communication. after discussing the communication theory of cdma, we propose the model of the ( cd ) 2ma communication system and utilize the simulation tools of matlab simulink to propose the ( cd ) 2ma simulation system according to this model
在論述了碼分多址通信原理的基礎上，給出了混沌數字碼分多址（ （ cd ） ~ 2ma ）通信系統的模型，並依據此模型使用matlabsimulink模擬工具給出了混沌數字碼分多址通信系統的可視化模擬系統。
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