頻譜擴展 的英文怎麼說
中文拼音 [bīnpǔkuòzhǎn]
頻譜擴展
英文
spectrum spread-
With dispersion, xpm can induce intensity fluctuations and timing jitter of the pulses in the receiver. it can also cause the spectral spreading of the channel so that crosstalk is introduced. all these effects put a tight limit on the capacity of the systems
它與色散共同作用，會導致接收端光脈沖的變形（強度起伏） 、光脈沖的時間抖動以及通道的頻譜擴展，這些後果都會限制系統的性能。1 ) the ground clutter is very strong when radar works in its down - look mode. 2 ) the clutter has the character of space - time coupling and the clutter spectrum spreads due to the movement of platform. 3 ) the lower repeat frequency results in doppler blur and the clutter spectrum spreads in the whole doppler domain
地面動目標檢測的最大難點： 1 ）雷達下視時地雜波特別強; 2 ）由於平臺運動，地雜波存在著空時耦合，雜波譜展寬； 3 ）為避免距離模糊，採用較低的重復頻率，但會存在多普勒模糊，地雜波譜擴散到整個多普勒域。When signals pass high power amplifier, they would be distorted in amplitude and phase, leading to spectrum spread and distortion of in - band signals, both of which would weaken performance of the whole system in turn
在無線通信中，信號在通過高功率放大器時會產生幅度和相位失真，造成頻譜擴展以及帶內信號畸變，導致整個系統性能的降低。It mainly includes two parts : the frequency offset caused by the difference of the mobile equipment ’ s transmitting frequency and the nodeb ’ s receiving frequency ; the frequency offset caused by the vehicle of the mobile equipment, which is called doppler shift. accurate frequency offset estimation and compensation is of importance for demodulation
它主要由兩部分構成:由於nodeb （基站）和移動臺晶振本振頻率的不同而產生頻偏;由於移動臺運動產生多普勒效應，引起的多普勒頻偏，在信號功率譜上表現為多普勒頻譜擴展（以後簡稱多普勒擴展） 。By theory and practice simulation, the several types of constant envelope modulation techniques are analyzed and compared, including theirs modulation principle, phase path, the modulated wave envelope, power spectrums, error bit rate and the influence of its power spectrums of the band - limited and non - linear, etc. especially we have researched the ijf - oqpsk modulation technique, and the performance of its inter - symbol interference and time jitter free, and its strongly resisting of spectral spreading
結合理論和實驗模擬結果，分析討論了衛星通信中的各種恆包絡調制技術，對它們的調制原理，相位路徑，已調波包絡，功率譜密度，誤碼性能，以及帶限非線性通道對其功率譜的影響等方面都作了研究和比較。特別研究了ijf ? oqpsk在消除碼間干擾和定時抖動方面的性能及其優良的旁瓣特性和抑制頻譜擴展特性。Over the air service provisioning of mobile stations in spread spectrum systems
頻譜擴展系統中移動站的空中服務保障In the first session the fans vibration on - line monitoring system is realized with vc language, also compile auto power spectrum density function, cross power spectrum density function, autocorrelation function and cross correlation function etc spectral analysis function to carry through simple offline fault diagnosis
首先用穩定性強、擴展性好的vc + +語言開發了通風機振動在線監測系統，並編寫了自功率譜密度函數、互功率譜密度函數、自相關函數和互相關函數等頻譜分析函數來進行簡單的離線故障診斷。From the research of ijf - oqpsk, we draw the conclusion that, compared with bpsk, qpsk and msk modems, in the band - limited and non - linear channel, it has nearly constant envelope, less spectral spreading, better pe performance and the less interference of the adjacent channel, et. so, it is more suitable for the satellite communication channel
通過對ijf ? oqpsk的分析研究可知，它相對于傳統的bpsk和qpsk調制方式，在帶限非線性通道下，具有包絡近似恆定，頻譜擴展小， eb no惡化小，對鄰道產生干擾弱等優點，因而它更適合於衛星通道。The algorithin adopts two well - known ideas called spread spectrum and quantization, first applies a frequency transformation on the motion signal, and then embeds watermark bits by quantizing proper intermediate frequency coefficients
本章的演算法應用了量化與擴展頻譜的思想，首先對運動信號進行頻域變換，在dct域上選擇一定數量的中頻交流系數量化嵌入水印信息。Chapter 2 explain the base of mathematics, the mode of system, the principle of communication and the principle of pn code, and go along analysis of mathematics
第二章是擴展頻譜通信的數學基礎、系統模型、通信原理和偽隨機編碼原理，並進行了數學分析。Analyzing the response under the wind power, it includes response frequency of the extended mode, shaking model of the extended modeu response spectrum of the extended model
、分析橋機在風載下的響應，這包括擴展模態的：響應頻率、振型、響應譜。Direct - sequence spread spectrum communication system simulation
直接序列擴展頻譜通信系統模擬This paper designs an in - building power line dsss communication system after analyzing the properties of power line channel in detail
本文在對電力線通道特徵詳細分析的基礎上，設計了室內電力線直接序列擴展頻譜通信系統。Enhanced variable rate codec speech service option 3 for wideband spread spectrum digital systems
寬帶頻譜擴展數字系統用增強的可變率編譯碼器語音服務選擇3Evrc 3 software distribution for tia - 127 - a - enhanced variable rate codec speech service option 3 for wideband spread spectrum digital systems
Tia - 127 - a的軟體配置.寬帶頻譜擴展數字系統用增強的可變率編譯碼器Short message services for spread spectrum systems
頻譜擴展系統簡訊服務High rate speech service option 17 for widebande spread spectrum communications systems
寬帶頻譜擴展通信系統用高速語音服務選擇17A tdrss user transponder is a terminal of the user satellite in this system, in which qpsk or sqpsk modulation and direct sequence spread spectrum ( ds - ss ) are employed in the forward / backward links
Tdrss用戶應答機是該系統的用戶終端，其正反向鏈路的信號通常採用qpsk或sqpsk調制和直接序列頻譜擴展。Multicarrier wireless communications have been widely investigated in the past decades. recently, two - dimensional spread spectrum ( 2d - ss ) system has drawn a lot of attention because of its full utilization of spreading characteristics in the frequency domain and time domain. compared with multicarrier code division multiplex access ( mc - cdma ), 2d - ss system can effectively mitigate multiple access interference ( mai ) due to spreading in the time domain
當前多載波無線通信技術得到了廣泛的研究，二維擴頻通信系統是近年來提出的新的擴頻通信方式，由於二維擴頻系統從時域和頻域上分別對數據信號進行頻譜擴展，因此它同時具有時域擴頻和頻率擴頻通信系統的特點，是對傳統的一維時域直接序列擴頻和多載波擴頻的推廣。It follows that the description of characteristics of g programming language in labview and the process of building virtual instruments. the paper provides a new spectrum analyzing method of the combination of spread spectrum with fft. at last it gives the arithmetic realization and programming diagram of every part of spectrum monitoring and signal searching
介紹了labview下如何通過計算機介面獲取數據的過程，數據採集過程中各個參數的演算法選擇；同時闡述了labview平臺下g語言的特點及構建虛擬儀器的過程，然後介紹了信號分析處理部分採用的頻率擴展與fft相結合的頻域分析方法；頻譜監測部分各個模塊的演算法實現；最後給出了信號搜索部分的演算法實現及其原理框圖。分享友人