查询词典 radio-frequency spectrum

In this article,the frequency spectrum characteristic of the earthquake has been described by fourier amplitude spectrum, power spectrum and response spectrum.

而对地震动频率特性的描述则采用了已被工程界所广泛接受的反应谱、功率谱和傅氏谱。

The spectrum analysis of the air-ultrasonic waveform indicates that when the matcher thickness is calculated at the highest spectrum and the subsequent higher spectrum of the pulse waveform, it can obtain a better result. But all the highest spectrum of the air-ultrasonic waveform moves to the high frequency zone in the experiment, which is a possible important reason that the testing extent of the air-ultrasonic transducer is limited.

经对空气超声波形进行频谱分析后发现用脉冲波形的最高谱线及次高潜线对应的频率计算匹配层厚度，可得到较好的匹配结果，但是空气超声波形的最高谱线均移向高频段，这可能是造成脉冲空气超声换能器可检测的范围有限的一个重要原因。

TO this end the possibility of applying SSB broadcasting to radio has been suggested in the psat as a means of alleviating the overcrowede broacast bands of the frequency spectrum. In 1979 the World Administrative Radio Conference passed a resolution to improve the untilisation of the spectrum by the future application of SSB broadcasting.

作为减轻广播波段频谱过分拥挤的手段，应用单边带进行无线电广播的最终可能性过去曾被推荐。1979年世界无线电行政大会通过了一个决议以将来应用单边带广播来改善频谱的利用。

Solar radio bursts are usually accompanying with solar flares. The complicated radio spectrum detected in solar radio bursts contained a lot of important information on their source region including physical environment and emission mechanism. Especially, because of their morphologic features of short duration, rapid frequency drift, complicated types and so on, the microwave fine structures could bring out rich important information on the source region such as the complicated configuration of magnetic reconnection, the movement of energetic particle, etc.

太阳射电爆发通常发生在太阳耀斑期间，它携带着爆发源区的物理环境以及辐射机制等诸多重要信息，尤其是微波爆发的精细结构，持续时间短、变化快、结构复杂，可以反映重联过程复杂的磁场结构、高能粒子运动等许多特征。

This experiment is in frequency adjustment X-mitter about that miniwatt frequency adjustment X-mitter operating principle, analyses the debugging making method and their installation, the microphone changes implication into an audible signal, wave an audible signal being modulated as a result of enlarging the day afer tomorrow being in progress to the carrier wave , producing frequency adjustment, by the fact that air wire launching the frequency adjustment electromagnetic wave to the outside , the radio set just can with frequency adjustment meet hear clear implication.

本毕业设计是关于小功率调频发射机工作原理、分析制作方法及其安装调试，在调频发射机中，话筒将话音转化为音频信号，音频信号经放大后对载波进行调制，产生调频波，通过天线向外发射调频电磁波，用调频收音机便可以接听到清楚的话音。

The realization monolithic integrated circuit system double audio frequency, this radio has used double audio frequency decoding chip MT8870, demodulates the tonic train signalling from the frequency-modulated signal, and separates the double tonic train signalling from the tonic train signalling to enter the double audio frequency decoding electric circuit implementation letter command to decode, thus carries on the low gear rate using the frequency modulation channel the control command transmission.

为实现单片机控制的双音频解码，本收音机采用了双音频译码芯片MT8870，从调频信号中解调出音频信号，并从音频信号中分离出双音频信号进入双音频解码电路实行信令解码，从而利用调频信道进行低速率的控制指令的传输。

Radio Frequency Identification System BE make use of RF energy to deliver data,belong to a wireless communication technique,is 1 kind not the system of contact type,it constitutes the component contain the application system of the reader,electron label,Antenna,host computer, its induction method depends on passive type Tag with active type Tag distinguish analyse, can be divided into induction coupling and back scattering coupling and induced the coupling is the induction method (as 135 KHzs、13.56 MHzs) which belongs to low frequency、high frequency,the back scattering coupling is the induction method(as 915 MHzs、2.45 GHzs) which belongs to superhigh frequency,microwave, and what we construct apply system is use the high frequency 13.56 MHzs of induction coupling method.

中文摘要无线射频辨识系统(Radio Frequency Identification；RFID)是利用RF能量来传递资料，属於无线通讯技术，是一种非接触式的系统，其组成元件有读卡机、电子标签、天线、主电脑应用系统，其感应方式依被动式Tag和主动式Tag来区分，可分为感应耦合和反向散射耦合而感应耦合是属於低频、高频的感应方式(如135KHz、13.56MHz)，反向散射耦合是属於超高频、微波的感应方式(如915MHz、2.45GHz)，而我们所建构的应用系统是使用高频13.56MHz的感应耦合方式。

The present paper uses the direct sequence spread spectrum technology, key to short-wave communication and direct sequence spread spectrum correspondence characteristic as well as union advantage, wide frequency code production, the direct sequence spread spectrum communications system technology and the principle, the wide frequency synchronization technology, the RAKE receive technology has conducted the research and the analysis.

本论文采用直接序列扩频技术，重点对短波通信与直接序列扩频通信的特点以及结合的优点，扩频码的产生，直接序列扩频通信系统的技术与原理，扩频同步技术，RAKE接收技术进行了研究与分析。

This paperexplores the way to analyze the time domain amplitude spectrum , frequency domain power spectrum and inverse frequency spectrum todetect faults with AI technology, especially expert system.

本文探讨了利用智能技术特别是专家系统来进行旋转机械的时域幅值谱、频域功率谱及倒频谱分析，从而进行故障诊断的方法和途径。

The frequency spectrum of the electric field, produced by an electric current dipole on the surface of the uniform conductive and polarizable earth, is transformed into time spectrum, with or without some random error added, and the time spectrum is then inversely transformed into the frequency domain.

基于层状导电和可极化大地表面，电偶源电场的时间谱在无随机干扰和有随机干扰时，进行频谱转换的计算结果，证明了时—频转换的误差传递问题严重。

The use of the web to spread fears that flicking the switch on the LHC could create a Black Hole that could swallow up the Earth particularly concerned him, he said.

他说，使用互联网散布恐慌说启动LHC会生成一个可能吞噬地球的黑洞的做法让他感到忧虑。

Not a single word have I written down.

我一个字也没有写下来。