頻濾下降 的英文怎麼說
中文拼音 [bīnlǜxiàjiàng]
頻濾下降
英文
decrease of frequency-
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。This text has finished the following several tasks mainly : first of all, through multianalysis and studying of the vibration theory of the gear wheel, draw the conclusion : effective time - frequency analysis is the inherent demand for analyzing the vibration signal of the gear wheel ; singularity monitoring and filtering the signal or depressing noise are the main applications of wavelet to gear wheel vibration signal analysis
本文主要完成了以下幾個任務：首先，通過對齒輪振動理論的全面分析與研究，得出結論：對齒輪振動信號進行有效的時頻分析是分析齒輪振動信號的內在需求；奇異性監測和對齒輪振動信號進行降噪濾波是小波變換在分析齒輪振動信號的主要應用。The development of filters, resonators and other telecommunication technology required better dielectric materials. the dielectric materials, used as the resonate body, should be high in dielectric constant, low in dielectric loss and a near zero temperature coefficient of dielectric constant in high frequency band, also could be sintered in a relative low temperature so as to reduce production cost, and what ’ s more, the miniaturization and reliability of materials are also the main aspects in the research work of high frequency band dielectric materials
隨著濾波器、諧振器等器件以及通信技術的發展，人們對電介質材料的要求越來越高，要求作為介質諧振腔的電介質材料在高頻段下具有高介電常數，低介電損耗，接近於零的介電常數溫度系數，還要求高頻電介質材料能夠在較低的燒結溫度下燒成，以降低實際生產的成本，此外，材料的小型化，高可靠性也是高技術高頻介質材料的重要研究方向。The problem of signal processing for direct - sequence code - division - multiple - access ( ds - cdma ) signal over multipath frequency - selective mobile channels is considered. a new blind receiver is proposed. without the knowledge of the multiple - access interference users spreading code and the channel characteristics, the receiver achieves blind detection with prior knowledge of only the desired users spreading code and approximate timing. by using reduced rank adaptive decorrelating filter and adaptive multipath combiner which is based on decision - directed algorithm, the receiver gets the ability to combat both fading and the near - far effect at low cost. simulation results demonstrate that the proposed receiver offers high performance
本文研究多徑頻率選擇性衰落通道下直接序列擴頻碼分多址（ ds - cdma ）信號的處理問題，提出了一種新型的盲接收機.該接收機不需預知多址干擾用戶的擴頻碼，不需預知通道參數，只需已知期望用戶的擴頻碼和粗略的定時，就可以完成用戶的盲檢測.同時，該接收機通過降維自適應去相關濾波和基於判決指導的自適應多徑合併，來獲得低成本和良好的抗衰落、抗遠近效應性能.模擬結果驗證了本文提出的接收機的優良性能分享友人