頻譜帶 的英文怎麼說
中文拼音 [bīnpǔdài]
頻譜帶
英文
spectral band-
Due to existing signal processing technology ’ s shortage such aslow measurement, narrow measurement range precision and other poor performance, we introduced a high - precise signal processing technology : firstly, to get power spectrum with hanning windowed welch modified periodogram, search its peak value frequency ; secondly, to apply zooming analysis via goertzel algorithm ; at last, to get a highly precise doppler frequency with energy centrobaric rectifying algorithm 。 the simulating result indicated that this technology introduced could get accurate doppler frequency 。 depending on above discussed technology, we designed a signal processing scheme, and developed a signal processing system. the running result showed high performance, verified the feasibility and reliability of the highly precise signal processing technology introduced. in a word, the technology improved ldv ’ s performance such as measurement precision, measurement range, dynamic response time 。 and it will have a wide application foreground
針對存在的缺點,本文提出了一種應用於激光多普勒測速的高精度信號處理技術,即首先利用加hanning窗的welch修正周期圖演算法得到信號功率譜,搜索其譜峰值頻率,接著利用goertzel頻譜細化演算法對搜索的譜峰進行細化分析,再引入能量重心頻譜校正演算法對細化后的譜峰進行校正分析,從而將離散頻譜分析演算法、頻譜細化演算法和頻譜校正演算法三者有機結合起來,充分發揮各自的優點:通過加hanning窗的welch修正周期圖演算法快速得到功率譜及峰值頻率,通過goertzel演算法獲得分析頻帶的高解析度頻譜,然後通過能量重心校正演算法對細化后的頻譜進行高精度校正,這樣不僅保證了演算法的高效性,而且大大提高了分析的精度。Electromagnetic compatibility and radio spectrum matters - electromagnetic compatibility standard for radio equipment and services - part 12 : specific conditions for very small aperture terminal, satellite interactive earth stations operated in the frequency ranges between 4 ghz and 30 ghz in the fixed satellite service v1. 2. 1
電磁兼容性和無線電頻譜情況.無線電設備和服務的電磁兼容性標準.第12部分:固定衛星服務中工作在4 ghz到30 ghz頻帶的衛星地面站微小孔徑端的具體條件The bandwidth ( megahertz ) and spectrum position of the signal arising from television scanning
電視掃描信號所佔的頻譜位置和帶寬(以兆赫計) 。Fundamentals and overtones of other bands in this region are not difficult to recognise.
在這個區域中其他譜帶的基振動或信頻是不難識別的。The radio spectrum used in narrowband personal communications services ( pcs )
用於窄帶個人通信業務( pcs )的無線頻譜。By using ofdm technology, we can redu ce the baud rate with a high frequency spectrum utility factor. another advantage of this technology is that the transmission can combat the intersymbol interference ( isi ) at the receiver without complex adaptive equalizer
Ofdm既有較高的頻譜利用率,也有效地降低了碼速率,在不使用復雜的通道均衡技術的條件下仍然可以較好地克服接收時由多徑效應帶來的碼間串擾( isi ) 。The method of compressing bandwidth of fringe function is proposed that basis fringe contains discrete spectrum which is based on human vision for real - time display, we also introduce discusses the spatial light modulators ( slms ) based on display system of digital holography and theory of numerical reconstruction of digital holography
為了達到實時性要求,在滿足人眼視覺的光信息量基礎上,對帶寬壓縮的理論問題進行了研究,提出了基於離散頻譜的帶寬壓縮演算法,並給出了結果。Each order rainbow can be separated and reconstructed from the interference intensity distribution, using low or band pass filtering for the interference spectrum of the intensity and ifft
提出了對干涉強度頻譜進行低通和帶通濾波、 ifft的方法,從干涉強度分佈中分離重建各階彩虹。In light of the limitation of fast fourier transform ( fft ) for the method of traditional spectrum analysis to analyze the unsteady signal, wavelet and wavelet analysis are made for the typical unsteady process signal of starting up and shut down with the good characteristic of simultaneous localization in both the time and the frequency domains based on the field test on the vibration of two - row placed units in lijiaxia hydropower station, in which the signal is decomposed into different frequency band, and then the weak signal is caught and the dominant frequency is picked up for the analysis of the vibration source
摘要基於李家峽水電站雙排機組振動的現場試驗研究,並且針對傳統頻譜分析方法傅立葉變換( fft )對于非平穩信號已力不從心這一缺陷,利用小波分析方法在時域和頻域上同時具有良好的局部化性質,通過對開停機這一典型非平穩過程信號進行小波及小波包分析,將其分解到不同頻帶內,獲取微弱信息和提取優勢頻率,並對其作振源分析,得出開停機初始時刻因水流不穩均出現強烈的振動現象,且低頻段信號能量最大,開停機過程水流脈動壓力和尾水渦帶擺動是引起定子基礎振動的主要原因。Electromagnetic compatibility and radio spectrum matters - meteorological aids met aids - radiosondes to be used in the 400, 15 mhz to 406 mhz frequency range with power levels ranging up to 200 mw - part 2 : harmonized en covering essential requirements under article 3. 2 of the r tte directive v1. 1. 1
電磁兼容性和無線電頻譜情況.氣象輔助裝置.用於功率電平200 mw及以下的400 . 15 mhz到406 mhz頻帶的無線電高空測候器.第2部分:包括r tte指令3 . 2條款基本要求的協調的enFemale courtship signal of the brown planthopper was made of many continuous regular pulses and male ' s signal was made of similar syllabics and had two types with different time domain characteristics. second male vibrational signal differed from male courtship signal with wide spectrum range and regular syllabics frequency. time domain characteristics of signals in different individuals even the same individual were different
頻域特徵分析知,褐飛虱雌蟲求偶嗚聲信號的頻域特性較穩定,個體內比個體間差異小;雄蟲求偶嗚聲信號s 、 e片段頻譜范圍較寬,但主振頻率比較接近,差異不顯著; m片段頻帶較窄,主振頻率mvf略小於s 、 e片段,變異較小; m片段脈沖重復頻率prf為幻These include the well - known am, fm, shortwave and citizens bands and vhf and uhf television channels, as well as hundreds of less familiar bands that serve cellular and cordless telephones, gps trackers, air traffic control radars, security alarms, radio - controlled toys and the like [ see box on page 71 ]
這些頻率包括眾所周知的am 、 fm 、短波、民用頻帶, vhf和uhf電視頻道,以及數百個較不為人知的頻帶,供行動電話、家用無線電話、 gps追蹤系統、航空管制雷達、安全警示與無線電遙控玩具等使用(見85頁無線電頻譜) 。In the terms of interpolation, the image reconstructed from nearest interpolation or linear interpolation has good edge but serious noise ; reconstruction from 4 * 4cubic interpolation or three b - spline or three - order lagrange interpolations has better local character. 2 x 2cubic interpolations which has both better edge and local character is the ideal interpolation, the following is the basic principle during reconstruction : ( 1 ) the more width of interpolation, the more number of summation and the more order of interpolation polynomial, the higher of density resolution ; ( 2 ) the more of interpolation polynomial and width of interpolation, the more of reconstruction time simultaneously, aimed at eliminating the effects of noise contained in projection data, in this paper, author analysis cause and effects of common artifacts. importantly, discusses convolution back - projection reconstruction algorithm with a shift axis of rotation has been derived for correcting images that acquired with a divergence axis of rotation using the fan beam geometry with an angle - equaled detector
在ct圖像重建時,選擇有限帶寬窗有較好的空間解析度,三角形窗有較好的密度解析度,選擇餘弦窗則使得空間解析度與密度解析度的折衷;從窗函數的頻譜角度來講,可以用於圖像重建的一個良好的卷積窗函數應該具備以下條件: ( ? )小的3db帶寬b ,即最小的主瓣寬度; ( ? )最小的旁瓣最大峰值a ; ( ? )最大的旁瓣峰值衰減速度d ;就內插函數而言,臨近點內插與線性內插重建圖像噪聲大,但有較好的邊緣與細節; 4 4三次內插、三次b -樣條與四次拉格朗日多項式內插圖像平滑,局部特性較好。But the bandwidth of the raw radar video is too wide to transmit directly in the common communication channel
但是雷達原始視頻信號頻譜很寬,要求傳輸設備有很寬的通頻帶,而且效率低、投資大。A data acquisition and analysis system of insect acoustic signal ( daasias ) with friendly interface, simple operation and multifunction was developed. it could sample and analyze insect acoustic signals in real time. by daasias both observing insect behavior and analyzing signal could be conducted at the same time
以往昆蟲鳴聲信號是記錄在磁帶上,分析時通過回放磁帶的錄音,在示波器、頻譜儀或聲譜儀等聲學儀器上進行信號分析,結果磁帶的多次回放常會引起信號的失真,並難以對信號作進一步的編輯處理;分析儀器不但價格昂貴、體積較大,而且很難實現昆蟲聲行為觀察與信號分析同步,更不適合野外工作。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。Telecommunications - electromagnetic compatibility and radio spectrum matters - radiotelephone transmitters and receivers for the maritime mobile service operating in vhf bands - part 1 : technical characteristics and methods of measurement v1. 3. 1
電信.電磁兼容性和無線電頻譜情況.工作在甚高頻帶的海上移動業務用無線電話傳送機和接收機.第1部分:技術特性和測量方法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。On the basis of high speed hybrid filter banks adc system, a kind of downsampler model based on bandpass sampling theorem is presented, and analyzed, proved in time and frequency domain, in addition a downsampler is designed according to the model. a class of high effective hybrid filter banks adc system which bases on the downsampler and radio frequency spectrum is proposed, of which digital signal rate falls m times as fast as the former
作者提出了一種基於帶通采樣定理的抽取器數學模型,對該數學模型進行了時域、頻域的分析證明后,設計了一種基於該數學模型的抽取器,進而根據無線電射頻信號頻譜的特點,提出了高效混合濾波器組adc系統,其數字信號輸出速率比高速混合濾波器組adc系統降低m - 1倍。Thus, the frequency domain adaptive filter is well suited to a multi - narrowband interference scenario, the paper studied frequency domain adaptive algorithms, carried out analysis and computer simulations. simulation results : for gold codes ds - ss signal of length 63, 4 interferences of signal to interference ratio ( sir ) 40 ub or 4 narrowband interferences of signal to interference ratio ( sir ) 40 db and frequency - spectrum bandwidth 12 percent of the whole bandwidth, the sir improvement is better than 20db
模擬結果指出,在輸入信號為干擾是4個等強度的多音干擾或4個頻譜帶寬占信號總帶寬12的強窄帶干擾(干信比為40db )的擴頻信號(碼長為63的gold碼序列)情況下,演算法的干擾抑制比均優於20db 。分享友人