carrier offset 中文意思是什麼
carrier offset
解釋
載波偏置-
The carrier wave is modulated directly by the baseband signal at several frequency point in l band and s band. firstly, this paper clarifies the theory of i / q modulation, elaborates evm and acpl, and analyzes the effect of amplitude and phase unbalance and dc offset on evm. secondly we review the basic principle of phase locked loop and it ’ s composing parts, including the basic conception and design method of pll frequency synthesizer, especially introduce the charge pump pll frequency synthesizer in detail
首先，在闡述i / q正交調制基本原理的基礎上，通過對誤差矢量和鄰近通道功率泄漏的詳細分析，定性、定量地討論了各種非理想電路因素（如相位不平衡、幅度不平衡、直流偏差等）對調制器性能的影響;其次，介紹了鎖相環的工作原理和基本組成部分，包括鎖相環的設計和環路濾波器的設計，特別詳述了電荷泵鎖相頻率源;第三，介紹了採用直接調制技術模擬衛星信號的射頻前端的設計;最後，對整個直接射頻調制系統進行測試，結果基本上達到了課題要求。 -
Carrier frequency offset
載波頻率偏置 -
Algorithms of carrier frequency offset estimation in ofdm system
系統載頻偏移估計演算法的研究 -
In the synchronous techniques based pilot symbols, here propose a frequency offset estimating arithmetic using discrete pilot symbols. we pick up integer times sub - carrier frequency offset from the same ofdm symbol and estimate exact
此外，在頻偏估計方面，推導出短訓練序列前後兩段時域符號間的關系，並利用此進行粗頻偏估計，使頻率偏移的估計范圍大大增加。 -
The main work can be summed up as follows : firstly, we studied the thermal - field properties of vcsels, and analyzed the influences of current spreading, material parameters and operating conditions on the temperature distributions. secondly, we began with the electrode voltage and calculated the equipotential s distributions, compared the distributions of voltages and current densities in different depths of vcsels, and then studied the influences of the oxide - confining region with different position or thickness, and the different sizes of the gain - guided aperture and emitting window on the distributions of the injected current density, carrier concentration and temperature in the active region. thirdly, we realized the coupling of electricity, optical and thermal - fields, worked out the threshold voltage, calculated the distributions of the injected current density, carrier concentration and temperature under different offset voltages, and analyzed the impacts of temperature profile and carrier density on the refractive index, fermi levels and optical - field
具體工作可以概括如下：首先，研究了vcsel的熱場特性，分析了電流擴展，材料參數和工作條件對于溫度分佈的影響；其次，從電極電壓入手，計算出激光器中的等勢線分佈，並對不同深度處的電壓和電流分佈進行比較，研究了高阻區的不同位置和不同厚度、限制層和出射窗口半徑的大小對電流密度、載流子濃度和溫度分佈的影響；再次，實現了電、光、熱耦合，求出了閾值電壓，計算了不同偏置電壓下的電流密度分佈、載流子濃度分佈和熱場分佈，分析了溫度和載流子濃度變化對折射率、費米能級和光場的影響；最後，給出了考慮n - dbr和雙氧化限制層時激光器中的等勢線分佈，分析了n - dbr和雙氧化限制層對vcsel電流密度、載流子濃度、溫度和光場分佈的影響。 -
Analysis of the carrier frequency offset of filterbank - based multi - modulation
基於波濾器組的多載波調制頻偏分析 -
Firstly the carrier phase with frequency offset is obtained with a parallel method
該演算法利用并行方法估計有頻差時的載波相位。 -
An algorithm suitable for carrier phase and frequency offset estimation in software radio is proposed
摘要提出一種適合軟體無線電的載波相位和頻差估計演算法。 -
Aimed at the characteristics that multi - carrier transmission is sensitive to frequency offset and require high synchronization performance, firstly multi - carrier ofdm technique is introduced, the influence of synchronization offset to ofdm system is analyzed and two kinds of typical synchronization methods are given based on pilot and cp in the paper
針對多載波傳輸對載波偏移敏感，對同步要求高的特性，論文首先介紹了多載波ofdm技術，分析了同步偏移對ofdm系統性能的影響，給出了基於導頻和循環前綴的兩種典型的同步方法。 -
Algorithm of carrier frequency offset estimation for psk signal based on dft
信號載波頻差估計演算法 -
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。 -
The problems of carrier frequency offset estimation under the condition of the agwn channel, frequency flat - fading channel and frequency selective - fading channel are studied in detail respectively
本文仔細研究了在高斯白噪聲通道下、頻率平坦衰落通道下和頻率選擇性衰落通道下高精度估計信號載頻偏差的問題，並對相應演算法提出了一些改進辦法。 -
This paper deals with problems of high accurate estimation of carrier frequency offset which is widely used in communication signals synchronization and frequency measurement. therefore, it ' is very importance for interception and location of signals
通信信號載頻偏差的高精度估計廣泛應用於通信信號的同步和頻率測量當中，因此，對于信號的截獲和定位具有非常重要的作用。 -
As in offset printing, digital offset color printing transfers the inked image from the image carrier to a blanket ， and from the blanket to the substrate
在膠印過程中，數字式彩色膠印會將著墨圖像轉移到一個轉移區上，再由轉移區轉移到基片上。 -
The simulation for qpsk shows that the algorithm can estimate the carrier phase and frequency offset accurately and reduce the system ber effectively
結果表明，用該演算法可以精確估計載波相位和頻差，有效地降低系統的誤碼率。 -
Based on the coherent reception theory of radio signals and the theory of digital signal processing, the effects of carrier frequency offset, sampling clock offset, and symbol timing offset on ofdm signals are exploited. a series of amendments and new algorithms is derived from the in being algorithms of guard interval based symbol timing and frequency offset estimation, frequency - domain frequency offset, sampling offset, and symbol timing offset estimation
以無線信號的相干接收和數字信號處理理論為基礎，就載波頻偏、采樣鐘偏差和符號定時偏差對ofdm信號的影響進行了分析，對基於保護間隔的符號定時與載波頻偏估計演算法和多種現有頻偏、采樣鐘與符號定時偏差的頻域估計演算法進行了研究，提出了一系列改進措施與新演算法。 -
Digital down converting is one of the key technologies of software radio. it can improve the efficiency and reliability of communications. lt is also important to realize software radio receivers. the paper focuses on the technologies involved in digital down converting, such as integer sampling - rate conversion, non - integer sampling - rate conversion and carrier frequency offset estimation algorithm. on the base of these, the paper analyzes applications of digital down converting in the hsp50214b programmable downconverter. the hardware and sofeware of the application of digital down converting are also introduced
數字下變頻技術是軟體無線電中的關鍵技術之一。該技術不僅有助於提高通信的有效性和可靠性，還對實現真正的軟體無線電臺有著重要的意義。本文對數字下變頻所涉及整數倍采樣率轉換、非整數倍采樣率轉換和載波初始頻差估計校正作了較深入的研究，並提出了一些實用高效的實現結構和演算法。 -
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。 -
Chapter 2. the influence of symbol, frequency and carrier offset to ofdm system is analyzed according to ofdm principles and typical sync methods are given
第二章依據正交頻分復用技術的原理，分析了符號偏差，頻率偏差和采樣偏差對系統的影響，給出了典型的同步方法。 -
After that, based on the above discussion and technology comparison, an improved nda ( non - data - aided ) carrier offset estimation algorithm is proposed which has the advantages of improved carrier offset estimation performance and can be realized by high - speed dsp chips
本文論述的方法無需以數據為輔助進行頻率和相位估計，特別適合於突發性通信。同時系統性能穩定，其低復雜度的設計易於高速dsp器件實現。
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