頻率差 的英文怎麼說
中文拼音 [bīnlǜchā]
頻率差
英文
difference of frequency-
And then facing the problem of the channel estimation of the adaptive modulation system, we conclude out the channel estimation algorithms on maximum likelihood ( ml ) estimation and maximum a posteriori ( map ) estimation under the condition of flat fading channel and selective fading channel in detail. to meet flat fading channel, we simulate the relationship of the ratio between the error covariance in map estimation and ml estimation and pilot symbol message length. the conclusion can be drawn from these results
接著，對自適應調制系統中的通道估計問題難點，詳細推導了平衰落通道條件下和選擇性衰落通道條件下最大似然（ ml ）估計和最大后驗概率（ map ）估計演算法，針對平衰落通道，我們模擬了map估計和ml估計的方差與導頻符號長度的關系，模擬結果表明，錯誤方差受多譜勒頻率的變化影響最大，並且對實際的自適應調制系統，導頻符號長度的取值超過20個符號長度時， map通道估計明顯優于ml通道估計。The methods of direct measurement with low precision such as frequency and time interval methods and the methods of indirect measurement with high precision such as beat frequency method, dual mixer time difference method and frequency difference multiplying method are supported on the platform. the fundamentals of each method are studied. the quantization error is analysed and the illustration is given for each method
該平臺支持直接頻率和時差法兩種較低精度的測量方法以及雙混頻時差法、差拍頻率法和頻差倍增法高精度的簡接測量方法，本文研究了各種測量方法的原理，對各種測量方法的量化誤差作了分析，並給出具體的實例。Cycle frequency - based blind beamforming shows the performance degradation due to cfe ( cyclic frequency error ). an improved algorithm is presented in literature 6, which adopting forgetting factor in estimation cyclic correlation matrix would largely depress the sensitivity of cab to cyclic frequency error. by using this method, the improved algorithms of the c - cab and ecab algorithms are presented in this dissertation
針對基於循環頻率的盲波束形成演算法對循環頻率誤差cfe （ cyclicfrequencyerror ）很敏感而導致演算法性能下降的情況，參照文獻[ 6 ]提出的遺忘因子cab演算法，提出了c - cab演算法以及基於特徵空間的盲波束形成演算法（ ecab ）的改進演算法。On the base of researching the theory of the scheme and analyzing the signal feature, it is obtained that the existence manners and character of distance information in the differential frequency signal. at the same time, a new conclusion is gained that the technology of frequency agility can decrease the constant error of system. it is also to say that frequency agility and frequency modulation fixed - distance fuze has the similar feature to random period frequency modulation fixed - distance fuze. according to the theory of address coding in the hopping - frequency communication, the paper presents the principle of selecting the frequency agility sequence which fit to the radio fuze and constructs the frequency agility sequence family based on the rs codes
在深入研究方案原理和分析信號特徵的基礎上，獲得了該體制引信差頻信號中，距離信息的存在形式和特點，得出了頻率捷變技術的引入降低了系統定距固定誤差這一新的結論，即頻率捷變調頻定距引信在定距性能上具有類似隨機周期調頻定距的特徵。本文引入跳頻通信地址編碼理論，結合無線電引信的具體特徵，提出了適用於無線電引信的頻率捷變序列的選擇原則，並構造了基於rs碼的寬間隔頻率捷變序列族。In digital relay, the percentage of noise will increase rapidly with the increase of sampling rate when derivation calculus is substituted by sampled difference term. to solve this problem, a new method using fragment function integrated with the least square algorithm is proposed in this paper. the influence of white noise is greatly reduced and the accuracy of the dead angle calculation is nicely improved after adopting the new method
在數字式保護中，如果用差分代替求導將導致噪聲的百分比誤差隨著采樣頻率的提高而劇增，本文對此進行了分析並提出了用分段樣條函數最小二乘法來計算電流波形的導數值，以便在提高采樣率的同時降低噪聲誤差的影響，並將其應用於基於32位浮點dsp的新型變壓器保護裝置。It is a rather well - known fact that bank - slope deformation and failure result from the coupling of earth ' s endogenic and exogenic geological processes, in which different dynamic - force factor has a different correlation to the evolution of bank - slope
摘要河谷岸坡的變形與破壞是地球內外動力耦合作用的結果，並且每一種動力地質作用對于岸坡變形失穩的貢獻程度不同，造成岸坡變形破壞頻率和規模的空間差異。Verification regulation of heterodyne frequency meter
外差式頻率計檢定規程E., the carrier frequency of a gaussian beam deviates from the resonant frequency of a fabry - perot etalon ), variations of the peak intensity, the position of the peak intensity and the dwdm systems, has received considerable attention. in this work, after taking into account the wavelength - depended reflectivity distribution profile of a fiber bragg grating, the oscillation wavelength # _ ( 1 ) of long external cavity fiber bragg grat
與共振情況（即高斯光束的載波頻率與法布里一拍羅濾波器的諧振頻率一致）相比，非共振條件（即高斯光束的載波頻率與法布里一拍羅濾波器的諧振頻率存在偏差）一透射光束的峰值強度、峰值強度所對應的位置、以及光斑的大小隨入射角的變化都發生了顯著的改變。The doppler frequency can be obtained as a heterodyne or beat effect.
由於外差或頻差效應，能夠得到多普勒頻率。Mixers are the key components of many microwave and millimeter - wave systems. the super - heterodyne receiver is always applied in modern communication system, mixer becomes the key component as is at the first part of system. but it is more and more difficult to get the choiceness lo source of the same band with the system is working at high frequency especially in the millimeter - wave. sub - harmonic mixer is a good solution to this problem now. in this circuit we need just half 、 quarter 、 even 1 / 8 of the rf signal frequency. in this paper the design and fabricate of sub - harmonic hmic mixers ( 2, 4 ) at w - band are introduced
混頻器是微波通信、射電天文學、雷達、等離子物理、遙控、遙感、電子對抗，以及許多微波測量系統中至關重要的部件。在現代通信系統中，毫米波頻段通常採用超外差接收機，混頻器作為第一級就成為關鍵部件。由於在毫米波頻段，同頻段高性能的本振源成本高，技術難度大，採用分諧波混頻技術是解決此問題的有效途徑，只需射頻頻率1 / 2 、 1 / 4甚至1 / 8的本振頻率即可實現混頻。The ring laser gyro ( rlg ) is a new photoelectric inertia sensor based on the optic interference theory. it uses the difference between the frequency of the two beams of light, which run in the opposite direction in the resonant cavity, to measure the carrier ’ s rotate speed and the orientation in the inertial space
環形激光陀螺儀（ ringlasergyro ，簡稱rlg ）是以光學干涉原理為基礎發展起來的新型光電慣性敏感儀器，它利用環形諧振腔內順、逆運行的兩束光的諧振頻率差來測量載體對于慣性空間的轉速和方位。Semiconductor, diodes, bipolar junction transistors, field - effect transistors, transistor amplifiers, frequency response, operational amplifiers, differential and multistage amplifiers, integrated circuits
半導體、二極體、雙極電晶體、場效電晶體、電晶體放大器、頻率響應、算放大器、差動及多極放大器、積體電路。The specific research methods are listed : 1. matched filter taking the max ouput snr as the best rule correlates nonstop divided signal and divided echo to detect low snr target signal. then all one dimension divided correlation outs and done fft in portrait to leach interferential signal such as static or low rate mussy meaves, many pathway echo and so on and to take target ' s time difference and doppler frequency that combine parameters that target ' s direction taken from antenna and so on to implement target ' s orientation and tracking
具體研究方法如下： 1 、採用以輸出信噪比最大為準則的最佳匹配濾波器來對分段的參考和目標信號作相關處理來檢測低信噪比目標信號，然後對一維分段相關輸出組作縱向傅立葉變換來濾除靜態或低速的雜波、多徑回波等干擾信號，並提取目標的時差和多普勒頻率，再結合由天線獲得的目標方向等參數，就可以實現目標的定位和跟蹤。22 paired inferior collicular neurons were obtained in the experiment. the neurons were recorded in the depth of 198 - 1254 u m ( 544. 59 ? 72. 37 n m, m + sd ), and their bfs were 11. 25 - 59. 29 khz ( 26. 77 + 9. 95 khz, m ? d ) : the minimum thresholds ( mts ) werelo - 66 db spl ( 38. 14 ? 14. 39 khz, m + sd ) ; the latencies were 4. 0 - 16. 0 ms ( 8. 19 + 3. 14 ms, m + sd ) ; the best intervals between paired sound pulses were 0. 01 - 28. 71 ms ( 3. 93 + 2. 52 ms, m ? d ) 0 the results showed : l ) there were interactions between the neurons in the iso - frequency lamina and hetero - frequency lamina which included mutual inhibition ( 18 / 22, 81. 8 % ) and mutual facilitation ( 4 / 22, 18. 2 % ), and the mutual inhibition in iso - frequency lamina was stronger than that in hetero - frequency lamina ; 2 ) the mutual inhibition decreased with sound level increasing ( p < 0. 001, anova ) ; 3 ) the analysis of the inhibition of discharge rate at lodb above mt showed that the inhibition increased when the paired neurons " bfs difference decreased ( r = - 0. 545, p = 0. 0006 ) ; 4 ) the mutual inhibition of paired neurons can sharpen the frequency tuning and the effect increased when the frequency was away from the bf ; 5 ) the changes in q10, q30 decreased with bfs difference of the paired neurons increasing ; 6 ) the mutual facilitation between paired neurons not only increased discharge rate, but also widened the frequency tuning, i. e., increased response frequency
結果表明： 1 ）同頻層神經元之間或者非同頻層之間神經元之間存在相互作用，這種作用既有相互抑制（ 18對，佔81 . 8 ） ，也有相互易化（ 4對，佔18 . 2 ） ，且同頻層神經元之間的相互抑制作用較非同頻層神經元之間的相互抑制作用要強； 2 ）神經元對低刺激強度反應時，所受到的相互抑制作用較強，隨著聲刺激強度加大，抑制作用逐步降低（ p 0 . 001 ， anova ） ； 3 ）對閾上10db放電率抑制百分比進行的分析顯示，配對神經元之間的最佳頻率差越小，相互抑制作用越強（ r = - 0 . 545 ， p = 0 . 0006 ） ； 4 ）配對神經元之間通過相互抑制作用可表kx碩士學位論文waiaster 』 sthesis現出調諧銳化作用，該作用的效率與頻率有關， bf處的銳化作用較低，偏離bf時其銳化作用逐步加強； 5 ）頻率銳化作用的效率與bf差有關，隨著配對神經元之間的bf差擴亢q10 ， q30值的變化逐漸減小，其變化百分比與配對神經元之間的頻率差存在明顯相關； 6 ）配對神經元之間的相互易化作用不僅表現在放電率增加上，也表現在頻率調諧曲線的擴寬，即頻率響應范圍擴大。It showed that the differences of allele frequency among the populations regenerated from the accession samples with different germination level or the populations obtained from the accession samples with different generations were not significant, and there was no absence of rare alleles observed
結果表明，無論每一份不同更新發芽率水平繁殖後代的種質之間，還是每一份不同繁殖世代數種質之間，其等位基因頻率差異不顯著，也沒有檢測到稀有等位基因缺失的情況。The relations between accuracy, convergence of natural frequencies and transverse elastic displacement shape function, quantity of elements were discussed
計算實例表明，不同位形的機器人的頻率差別很大。Analytic technique of frequency difference for discrimination of cavity fillers
溶洞充填物判識的頻率差異分析技術The method for checking if transition interference is that transmitting a pure carrier, and monitoring it at downlink
（頻率遞增或遞減的原因為，地球站的上、下行頻率差與衛星的上、下行頻率差有著微小的差別。 ）Based on the configure of direction finding, the location method, algorithm, accuracy and performance for multistations and single station are studied in this thesis, and the computer simulation results are given out. it is important of resolving the performance of antenna array. a technique to estimate and calibrate the performance is developed in this page
本文以測向系統的組成為基礎，研究了單平臺情況下利用到達方向、到達時間差、多普勒頻率差、相位變化率等參數的測向方法、測向演算法、測向精度和性能，並進行了計算機模擬，為無源測向系統的設計和實施提供了重要的理論基礎和實驗數據。The survey also found that it is likely that prostitutes in mainland china were more easily persuaded to not using condoms, as compared to their counterparts in hong kong
研究亦發現，內地的妓女似乎較香港妓女容易被說服不用安全套，這可能是嫖客在港及在大陸用安全套頻率差異的原因之一。分享友人