Spread Spectrum扩展频谱
Spread Spectrum扩展频谱
相关考题：
主要的扩展频谱技术包括()。 A.直接序列扩频(Direct Sequence Spread Specm，DSSS)B.跳频扩频(Frequency Hopping Spread spectunu FHSS)C.跳时(Time Hopping，TH)D.线性调频(Chirp )
根据下面的文字资料回答 71～75 题 In the following essay．each blank has four choices．Choose the best answer and write down on the answer sheet．Spread spectrum simply means that data is sent in（ 1 ）pieces over a number of the discrete frequencies available for use at any time in the specified range．Devices using（ 2 ） spread spectrum(DSSS)communicate by splitting each（ 3 ）of data into several parts and sending them concurrently on different（ 4 ），DSSS uses a lot of the available（ 5 ），about 22 megahertz(MHz)．第71题：文中（ 1 ）处正确的答案是（ ）。A．smallB．highC．lowD．long
●In the following essay，each blank has four choices．Choose the best answer and write down on the answer sheet．Spread spectrum simply means that data is sent in (66) pieces over a number of the discrete frequencies available for use at any time in the specified range．Devices using (67) spread spectrum(DSSS)communicate by splitting each (68) of data into several parts and sending them concurrently on different (69) ,DSSS uses a lot of the available (70) ，about 22 megahertz(MHz)．(66) A．smallB．highC．lowD．long(67) A．direct-sequenceB．discrete-sequenceC．duplicate-sequenceD．dedicate-sequence(68) A．dataB．byteC．packetD．bit(69) A．bitsB．frequenciesC．packetsD．messages(70) A．rateB．velocityC．bandwidthD．period
关于维纳频谱的叙述，错误的是A、维纳频谱即Wiener spectrum，(WS)B、△D(x)的自相关函数的付氏变换为WSC、用WS分析形成X线照片斑点的原因D、维纳频谱可以确定不同频率的RMSE、维纳频谱也称量子检出效率
In the following essay, each blank has four choices. Choose the best answer and write down on the answer sheet.Spread spectrum simply means that data is sent in(66)pieces over a number of the discrete frequencies available for use at any time in the specified range. Devices using(67) spread spectrum (DSSS)communicate by splitting each(68)of data into several parts and sending them concurrently on different (69), DSSS uses a lot of the available(70), about 22 megahertz (MHz).A．smallB．highC．lowD．long
Spread spectrum simply means that data is sent in small pieces Over a number of the(46)frequencies available for use at any time in the specified range. Devices using(47)spread spectrum (DSSS)communicate by(48)each byte of data into several parts and sending them concurrently on different(49). DSSS uses a lot of the available(50), about 22 megahertz (MHz).A．continuousB．highC．lowD．discrete
Which spread spectrum technology does the 802.11b standard define for operation()。 A.IRB.DSSSC.FHSSD.DSSS and FHSSE.IR, FHSS, and DSSS
扩频通信技术，即扩展频谱通信（Spread Spectrum Communication），它与（）一同被誉为进入信息时代的三大高技术通信传输方式。A、光纤通信B、无线通信C、卫星通讯D、宽带通讯
在After Effects 6.5里，对于声音频谱（Audio Spectrum）和声波（Audio Waveform）这两个特效与音频（Audio）特效组的区别是：（）A、可以对音频层直接施加声音频谱（Audio Spectrum）和声波（Audio Waveform）这两个特效B、可以对音频层直接施加音频（Audio）特效组中的特效C、可以对固态层施加声音频谱（Audio Spectrum）和声波（Audio Waveform）这两个特效D、可以对固态层直接施加音频（Audio）特效组中的特效
主要的扩展频谱技术包括（）。A、直接序列扩频(Direct Sequence Spread Specm，DSSS)B、跳频扩频(Frequency Hopping Spread spectunu FHSS)C、跳时(Time Hopping，TH)D、线性调频(Chirp )
Which spread spectrum technology does the 802.11b standard define foroperation？（）A、IRB、DSSSC、FHSSD、DSSS and FHSSE、IR，FHSS，and DSSS
在After Effects 6.5里，对于声音频谱（Audio Spectrum）和声波（Audio Waveform）的使用方法描述准确的是：（）A、可以对音频层直接施加这两个特效B、可以对固态层施加这两个特效，并在Audio Layer中指定用于处理的音频层C、图形化的声音频谱或波形可以沿层的路径显示D、图形化的声音频谱或波形可以与其他层叠加显示
多选题主要的扩展频谱技术包括（）。A直接序列扩频(Direct Sequence Spread Specm，DSSS)B跳频扩频(Frequency Hopping Spread spectunu FHSS)C跳时(Time Hopping，TH)D线性调频(Chirp )
单选题Which spread spectrum technology does the 802.11b standard define for operation?（）AIRBDSSSCFHSSDDSSS and FHSSEIR, FHSS, and DSSS
单选题频谱直接扩展后的序列被送去进行射频调制，输出的是（）的射频信号。A扩展频谱B高频载波C音频信号D微波信号