頻帶中心 的英文怎麼說

Contrapose to the instability of the third - order charge - pump pll system, the loop optimization method is employed in system level design to decide the bandwidth and phase margin, therefore the loop bandwidth locates at the maximum phase margin to guarantee the stability of the system. according to tsmc 0. 35 m sige bicmos model, the sub - circuits in the designed pll and the whole system are simulated and verified by the cadence spectre

5 .根據tsmc0 . 35 msigebicmos工藝模型，利用cadencespectre模擬軟體對所設計的電荷泵鎖相環路中各個模塊及整個系統進行了模擬模擬，模擬結果顯示，在1 . 5v電源電壓下，頻率為200mhz的參考輸入信號，輸出中心頻率為800mhz ，分頻電路採用4分頻，環路帶寬為10mhz ，捕獲時間大約為0 . 92 s ，功耗大約為15mw ，達到了設計指標。

An lpf can be simulated by setting the bpf ' s centre frequency to zero

將帶通濾波器的中心頻率設置到0 ，就可以模擬低通濾波器。

The center frequency of the vco is 14. 14ghz with band width of more than 100mhz. the output power is 2 ~ 6mw

根據測試結果，該vco電路的中心頻率為14 . 14ghz ，調頻帶寬大於100mhz ，帶內輸出功率在2 6mw之間。

In designing the complex weights for center frequencies of each sub - band, an optimizing method using semi - definite programming " is proposed

在設計各子帶中心頻率上的恆定束寬加權時，提出了一種半定規劃的優化方法。

The dynamo runs at rull speed to drive main shaft, then the main shaft makes the emulsifying wings in emulsification grove rotate, which absorbs the liquid in its brand groove into ring groove through guide vanes on upper and lower sides of the groove. the vanes spins circularly at high speed with the main shatf as center, and the blade and emulsificaton groove cut and crush it continuously. after that. it gers squeezed by the vanes highspeed centrifugal rotation. at last, it finishes isotropt emulsification tratment within extremely short time after continuous circulating mixing

由電動機全速運轉帶動主軸，經主軸轉動乳化框槽內之乳化翼片，使其將桶槽內之液體經框槽上、下兩側之導流葉片吸入環狀框槽內，經以主軸為中心高速圓周旋轉葉片；連續使乳化翼端刀面與乳化框間極小之間系高頻率之強力切割剪斷、粉碎，再借葉片高速離心旋轉排擠，持續循環混合，以極短之時間即可完成均質乳化之處理。

Our treatment shows in the raman effect case, mnls solitons, the same as nls solitons, keeps its energy, initial center and initial phase unchanged. however, the raman effect, not the same as nls solitons. reduces its amplitude, widens its width and under the same conditions, the self - frequency shift of mnls soltions is closer to the result of numerical simulation. in the raman effect together with frequency filters case, mnls solitons, the same as nls solitons, keeps initial center and initial phase unchanged and bandwidth - limited frequency filters can make the mean frequency of mnls soltion stand a steady value at the red side of the initial mean frequency, i. e. suppress the self - frequency shift of mnls soltions. and that, the other physical parameters of mnls soltion last stand a steady value. however under the same conditions, the steady value of the mean frequency of mnls soltions is closer to the initial mean frequency and the result of numerical simulation

有所不同的是， raman效應雖然不改變孤子能量，但會引起孤子峰值的下降和寬度變寬，且在同一條件下， mnls孤子微擾理論得到的自頻移比nls孤子微擾理論得到的更接近直接數值計算結果。有限帶寬的頻率濾波也不引起mnls孤子初始中心、初始位相的改變，選取適當的頻率濾波器參數值能使孤子的平均頻率穩定在初始平均頻率的紅側一穩定值，抑制了自頻移，而且孤子的各物理量最後都穩定在一穩定值，這些與nls孤子微擾理論都是類似的。有所不同的是，寬度為飛秒量級下， mnls孤子平均頻率的穩定值更接近初始平均頻率，更接近數值計算結果。

Radio - frequency noise jamming is an effective jamming to pulse compressed ( pc ) radar. it shows the best jam quality when it ' s bandwidth equals to the jammed signal ' s bandwidth and it ' s central frequency equals to that of the jammed radar ' s receiver

射頻噪聲干擾對脈沖壓縮雷達是一種有效干擾，在其帶寬等於雷達信號帶寬，中心頻率對準雷達的中心頻率時具有最佳的干擾品質。

Finally according to the above mentioned results, two universal ulpa were made and their performance were tested. these results indicated that on the whole, the values of parameters, such as sensitivity of each element, center frequency, relative bandwidth and cross coupling among near elements and so on, and their consistency all meet the ask of technique. therefore, both of transducers performance are favorable

最後根據上述研討結果，製作了兩個通用超產相控線陣換能器，並進行了性能測試，結果表明兩個換能器各陣元靈敏度、中心頻率、相對帶寬、相鄰陣元間串波等參數值及其一致性均基本滿足技術要求，換能器性能良好。

However, the paralleling communication can meet the requirements of high speed and fidelity in underwater signal transmissions. ofdm is a kind of novel paralleling transmission technology. the principle of ofdm is that the whole bandwidth can be divided into some subchannels, the high - speed serial signal stream is modulated by some orthogonal subcarriers

正交頻分復用（ ofdm ）是近年來數字通信中流行的一種并行傳輸新技術，其核心思想是將整個可用頻帶分割成多個正交子通道，將待傳輸的高速串列碼流并行的調制在這些子通道載波上。

The circular monopole ultra - wideband antenna has not only the extremely wide band in frequency domain, but also stable phase center, which makes the antenna radiate and receive the short pulse signals without any distortion, and suitable for various ultra - wideband communication systems or the single antenna of other multi - frequency operating communication systems

這種天線不僅具有極寬的阻抗帶寬，還擁有穩定的相位中心。這使得圓盤單極超寬帶天線可以不失真地收發時域短脈沖信號。所以該天線不僅適用於超寬帶通信中，還能夠作為復雜多頻工作系統的單一收發天線。

Generating lfm / nlfm signals whose intermediate frequency is 28mhz and bandwidth is 3mhz and 5mhz and time width is from 6us to 300us based on dds has been discussed in this dissertation. the conclusion is that the wave quality of lfm signal generating through dds is satisfactory and that of nlfm is not perfect

本文基於器件dds對產生中心頻率為28mhz 、帶寬為3mhz和5mhz 、時寬從6us到300us的不同時寬和帶寬的線性和非線性調頻信號方面進行了探討，得出了dds產生線性調頻信號（ lfm ）的波形質量可取得滿意的結果，但對產生非線性調頻信號（ nlfm ）的波形質量卻存在不足。

And the waveform of the transmitted signals was designed based on the target distance ( 5 ~ 50m ). the waveform is triangular fmcw with central frequency at 6ghz, modulation bandwidth 100mhz, modulation period 10 s, step frequency 0. 2mhz, and step time 10ns

在此基礎上，設計發射信號波形參數為三角形調頻連續波，中心頻率6ghz ，調制帶寬100mhz ，調制周期10 s ，步進頻率0 . 2mhz ，步進時間10ns 。

Nouns in news titles not only can be subjects and objects, but also can be adverbials to modify predicates directly. the verbs that refer to movement are most frequently used in news titles. verbs in news titles not only can be predicates or the key words of predicates, but also have some special usages such as verb - object structure with object, transitive verb with special object, ect

新聞標題中的名詞，絕大多數是表示人或事物的名詞，在語法上不僅經常做主語和賓語，還經常做狀語直接修飾謂語動詞;新聞標題中的動詞，動作動詞使用的頻率最高，在語法上不僅經常做謂語或謂語中心，還出現了動賓結構帶賓語、及物動詞帶特殊賓語等一些特殊用法;新聞標題中的形容詞，性質形容詞占絕大多數。

Due to restriction with the array aperture transition time, traditional phased array radar works under relative narrow signal bandwidth, so this restricts the application of phased array radar in the field where high performance is demanded. however, optically controlled phased array radar ( ocpar ) adopts the photoelectron technology, counteracts the aperture transition time via the method of optical true time delay ( ottd ), so it can realize wide instantaneous bandwidth and squint - free operation ; meanwhile, it can realize the miniaturization of phased array radar and has super anti - electromagnetism interference capability

而光控相控陣雷達採用光電子技術，通過光實時延遲的方法來抵消孔徑渡越時間，可以實現相控陣雷達的寬帶寬角掃描;同時也可以使得相控陣雷達小型化，並具有強的抗電磁干擾的能力;另外，由於光纖傳輸具有損耗低、頻帶寬等固有優點，採用光纖連接雷達天線和雷達控制中心，可以使兩者的距離較採用同軸電纜有較大的提高，更有利於保護雷達控制中心。

The adaptive front - end has the adaptive ability for the magnitude and frequency of input signals. it can prefilter for the input signals, eliminate the useless signals, and improve the dynamic range of receiver system. it can lessen the burden of digital signal processing in the back - end of receiver, and improve the performance of receiver system

自適應接收機前端對輸入信號有自適應能力? ?頻率自適應和幅度自適應，這樣的前端就可將系統的接收中心頻率和帶寬自適應到輸入信號的頻率和帶寬，其實就是對輸入信號進行一次預分選、預濾波，剔除對接收系統毫無作用的信號;同時對大信號自動減小增益，對小信號增加增益，提高系統的動態范圍;而且可以對干擾信號進行壓制。

In chapter 3, under the wideband radar system, some parameter estimation methods of scattering center are studied in the white noise and clutter background

第三章以寬帶階梯變頻雷達為研究背景，在白噪聲和雜波條件下，研究了提取目標強散射中心的參數估計方法。

It mainly includes following aspects : in this paper, firstly implication of wavelet analysis in signal harmonic component extraction is presented in detail, and on this foundation signal given frequency band component extraction method is proposed. then we investigate frequency aliasing phenomenon, reason why frequency aliasing phenomenon is easy happened when wavelet is implied in field of motor fault diagnosis, and frequency bands where frequency aliasing phenomenon is easer happened, and put forward approved morlet wavelet analysis method which can effectively alleviates frequency aliasing phenomenon. third we set up vibration signal detected system, design experiments to obtain three groups of fault signals : eccentricity fault, mixed fault of eccentricity plus mild rub, mixed fault of eccentricity plus moderate rub, and process these data using analysis method proposed in this paper

首先對論文的選題以及相關背景進行了探討，並對相關的小波基礎理論進行了闡述，主要針對感應電動機的偏心故障和偏心+碰摩復合故障形式及相關的應用演算法進行了詳細探討，主要工作內容包括下面幾個方面:在論文中，首先對小波分析在信號的諧波分量提取中的應用進行了研究，在此基礎上，提出了信號的特定頻帶成分的提取方法;研究了小波分析的頻域混疊現象，探討了小波分析應用於電機故障診斷領域時易發生頻域混疊現象的原因，以及混疊現象較易發生的頻帶，提出了可以有效減輕頻域混疊現象的改進的morlet小波分析方法;搭建了振動信號檢測系統，設計實驗採集得到三組故障數據:偏心故障，偏心+輕微碰摩復合故障，偏心+中度碰摩復合故障，並對這些數據應用本文提出的分析方法進行信號處理，提取出的特徵參數可有效區分這兩種故障形式;研究了基於matlab和labview的混合編程方法，完成了電機故障檢測系統的軟體開發。

In the third chapter, a methodologies to realize second - order band - pass filter with which center frequency tuned in a wide range using mcdi ( multiple output current - mode differential integrator ), these two kinds of mcdi are composed of pmos and nmos input transistors respectively, lastly we compare these two integrators " merits and disadvantages

第三章：提出了輸入級分別為pmos管、 nmos管的多輸出端電流模式全差分積分器，並由此構成了中心頻率連續可調的二階帶通濾波器，同時比較了二者的優缺點。

In this paper, difficulties such as the design of hts microwave passive component, the lithography technology, encapsulation and testing at low temperature etc. are solved. a hts delayline with center frequency at 4ghz, bandwidth of 4ghz is manufactured and tested. it ’ s group delay is larger than 10 ns

本文在解決高溫超導微波無源器件的設計、光刻工藝、密封封裝和低溫測量等難點的同時，對一個f _ 0 （中心頻率）為4ghz ，帶寬4ghz的高溫超導延遲線進行加工、封裝、測量，群時延大於10ns 。

But in the east, 30 ~ 60 - day low frequency propagates toward north and west and 10 ~ 20 - day low frequency spreads to south from mid - latitude as well as to east from 90 " e. 10 - 20 - day and 30 - 60 - day low frequent rain band centers, located in south china, upper - middle yangtze basins, northeast china, north china and the west part of china, are all important parts of asian summer monsoon rainfall

東部地區， 30一60天振蕩有明顯的向北及向西傳播; 10一20天低頻降水隨位相從中緯度向南傳播，同時從90 ? e向東傳播。東部地區的10一20天和30一60天低頻雨帶中心都是東亞夏季風降水的重要組成部分，當地的夏季風降水受這兩種低頻振蕩調制。