譜線頻率 的英文怎麼說
中文拼音 [pǔxiànbīnlǜ]
譜線頻率
英文
spectral line frequency-
The radio spectrum ? the segment of the electromagnetic continuum containing waves in the radio - frequency range ? accommodates countless communications devices today
無線電頻譜(一個連續的射電頻率范圍區段)容納了今日無數的通訊頻率。Study shows that the basic principles of three existed methods for phase difference correction on discrete spectrum are identical, by which the twice fft analysis through time - domain shifting time series or changing window ' s length is performed, and the spectrum by making use of the phase difference of two corresponding peak lines are finally corrected
在研究時域平移的離散頻譜相位差校正方法和改變窗長離散頻譜相位差校正方法的基礎上,發現這幾種離散頻譜相位差校正法的基本原理是一致的,就是通過時移和加不同的對稱窗進行兩次fft分析,並利用離散頻譜對應峰值譜線的相位差以求得頻率和相位校正量。The calibration of a spectrum analyser normally includes checks on frequency accuracy, level flatness, level linearity, input attenuation and calibration reference output
頻譜分析器的校正工作一般包括檢查頻率準確度、功率電平不平坦度、標度線性、輸入衰減及參考輸出值的校正。Experiments show that, when use msp430f149 audio sensor to identify vehicles that contain plane, tank, truck and so on by time domain features and two - level f - ratio, the recognition rate is 82. 1 % ; when use both msp430f149 audio sensor and arm9 sensor to identify vehicles, and the recognition rate is much better than the original system and msp430f149 audio sensor. line spectrum of power spectra and 3 / 2 spectrum is used as frequency features on arm9 sensor, and it is caught by narrow - band bandpass filter
實驗證明,在主頻為8mhz的msp430f149感知器上,採用基於時域特徵和二階f比的識別演算法,能夠實時地完成對飛機、坦克、卡車等交通工具的識別;將msp430f149感知器與基於arm9的高端感知器配合使用,且高端感知器採用功率譜線譜或3 / 2維譜線譜作為頻域識別特徵,能夠實時的對各類交通工具做更高性能的識別。Measuring frequency of received signal by a spectrum line ratio method
譜線比值法測量接收信號的頻率These developments will yield a cognitive radio able to sense its rf environment and location and then alter its power, frequency, modulation and other operating parameters so as to dynamically reuse whatever spectrum is available
以這些發展製作出來的感知無線電裝置,能感應所在的rf環境與地點,進而調整功率、頻率、調變及其他運作參數,以便靈活運用所有可用的頻譜。All - solid - state laser is an advantage lamp - house. it has many important applications and potential commercial value in many fields, such as industry, scientific research, military. so it ' s always the research focus of laser field. diode end - pumped solid - state laser has many merits. including high efficiency, long lifetime, high frequency stability, narrow line width, compact configuration, convenient for use et al, which made her a necessity in many high level quantum optics experiments. in this thesis, a series of experiment research was done with regard to blue laser, green laser and infrared laser
激光二極體端面泵浦的固體激光器具有效率高、譜線窄、壽命長、結構簡單、使用方便等優點,特別是採用環行諧振腔內加光學單向器構成的單頻激光器,由於頻率穩定,使其成為許多高水平量子光學實驗的主要光源。本論文圍繞全固態單頻藍,綠,紅外激光器進行了一系列實驗研究工作。This dissertation mainly studies the pulse compression waveform designing and signal processing, including the following aspects : firstly, by the pulse compression basic theory, the linear frequency modulation signal ( lfm ), binary phase - coded signal ( bc ) and stepped - frequency ( sf ) signal are discussed respectively including the ambiguity function, pulse compression and spectrum characteristic
本文主要進行脈沖壓縮雷達波形設計以及信號處理方面的研究,主要體現在以下幾個方面:首先,從脈沖壓縮基本理論出發,分別給出了線性調頻、二相編碼和頻率步進信號的模糊函數、脈沖壓縮以及頻譜特性,對多普勒性能進行了簡要分析。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) 。To improve anti - jamming technique by spread spectrum close to monochromatic frequency, so that enhance the ability of anti - active - jamming and anti - passive - jamming, anti reconnaissance, anti - radiation missile, anti - stealth, by means of multi frequency spread spectrum and hopping spectrum instead of mono - frequency spread spectrum, realizing strong processing system for anti - interference signal, providing the method of generating of chirp signal and corresponding matched filter system
摘要為改進線性調頻雷達系統所採用的在單色頻率點附近擴譜抗干擾技術,加強制導雷達站具備抗有源、無源干擾,反偵察,抗硬殺傷的反幅射導彈和反隱身的能力,通過將單頻點擴譜改為多頻點擴譜跳譜,實現了高抗干擾信號處理系統,給出方案中在中頻段實現的線性調頻信號產生方法以及對應的匹配濾波處理系統。Abstract : we have studied the polarization beats spectroscopy with phase - conjugation geometry in a cascade three - level system. it was found that the accuracy for the energy - level difference measurement is determined by the homogeneous linewidths of the optical transitions. under the condition for the occurrence of beating, the frequency difference of the beat between two independent light sources could exceed the laser linewidth. the measurement accuracy for laser absolute frequency could reach the same order of magnitude as the laser linewidth
文摘:研究了級聯三能級系統中的相位共軛極化拍頻光譜術.發現其對能級差的測量精度決定於光學躍遷的均勻增寬.在符合拍頻條件時,兩獨立光源拍頻的頻差可以超出激光線寬,激光絕對頻率的測量精度可達到與激光線寬同一量級A comprehensive theory is presented for fm spectroscopy of doppler - broadened molecular iodine absorption lines. the relationship betwcen fm spectroscopy and modulation frequency and modulation index has been studied. the whole circuit for thc frcquency stabilized laser system has been developed
建立了多普勒加寬碘分子線性吸收fm光譜的一般理論,對fm光譜與調制頻率和調制度的關系進行了研究;並研製了532nmnd : yvo _ 4 / ktp碘吸收穩頻激光器的電路系統;提出了虛擬激光穩頻技術的概念。Theoretical model of self - mixing interference in a linear frequency modulated laserdiode is presented by using the dynamic theory of semiconductor laser with weak external optical feedback. the characteristics of oscillation frequency shift and output power changes of the laser diode are analyzed by using the theoretical model. the absolute distance from front facet of laser diode to target can be found by measuring spectrum of output power of the laser diode
使用半導體激光器在弱反饋條件下的動力學理論,建立了線性調頻半導體激光器的自混頻干涉理論模型.基於該模型,分析了激光器振蕩頻率偏移與輸出功率變化特性.通過測量激光器輸出功率譜,可以得到激光器前端面與被測目標之間的距離The technology of frequency synthesis is important in latter - day communication system. it ’ s widely used in wireless communication and electron system. with the high - speed development of technologies, higher stability, higher purity, broader range and larger output number of frequency are required in the frequency source of frequency synthesizer which is the core of this technology
頻率合成技術是近代通信系統的重要組成部分,在無線電通信與電子系統的各個領域中得到了廣泛的應用。隨著各種技術的飛速發展,人們對頻率合成器的頻率穩定度、頻譜純度、頻率范圍和輸出頻率的個數提出了越來越高的要求。The concept of viffoal laser frequency stabilizaion is put fowi. the frequency stabilizaion at the center of doppler curve has been realized aller signal detecting, phase sensitive detecting, integrating and high voltage amplifying circuits with fm spectroscopy a frequency stability of l0 -, has been obtained with a reproducibility of l0 - 9. hyperfine spectra of, ', i, near 532nm have been studied via modul8tion tfansfer spectroscopy
利用fm光譜法將激光單次通過碘吸收室進行線性吸收,再經信號檢測、混頻、積分和高壓放大等伺服電路,實現了在多普勒曲線中心處的頻率穩定,頻率穩定度和復現性可達10 ~ ( - 9 )量級。Xrd, sem, temperature and frequency dependence of dielectric constant, and hysteresis loop were measured to investigate and study structure, microstructure, dielectric and ferroelectric properties of barium titanate dielectric ceramics
應用x光衍射譜、掃描電子顯微鏡、介電率的溫度與頻率依存關系以及電滯回線測量,調查和研究所制備的鈦酸鋇陶瓷的結構、微結構、介電和鐵電性質。Abstract : a software method of frequency - modulated signal demodulating based on wavelet packet is proposed in this paper. a variety of frequency - modulated signals are analyzed in time - frequency domain and the spectrograms are presented. this method can detect instantaneous frequency effectively and get frequency - modulated information, can be widely applied to dynamic testing and software radio
文摘:提出了基於小波包的調頻波解調方法,通過對各種調頻信號進行時頻分析,給出了信號的時間?頻率譜圖,能有效地檢測到瞬時頻率和獲取調頻信息,該方法可廣泛應用於動態測試和軟體無線電等領域。Code division multiple access ( cdma ) communications systems being possessed of the merits of great capacity and soft hand - off and so on must have taken a significant role in future wireless communications systems. because pn sequences used in communications systems are been vertical completely, when numbers of user are more, there are multiple access interference ( mai ) in cdma and serving quality in communications systems is reduced
碼分多址( cdma )通信系統以頻譜利用率高、系統容量大、頻率管理容易,軟切換、移動臺發射功率低、通道的傳輸速率高等優點代表了新一代移動通信,在未來的無線通信系統中必將扮演極為重要的角色。Mca histogram data interchange format for nuclear spectroscopy
核光譜學的mca頻率分佈曲線數據交換格式Method of measuring spectral emissivity of ceramic radiating materials for infrared heaters by using ftir
用ftir測量紅外線加熱器的陶瓷輻射材料頻譜發射率的測試方法分享友人