Which two statements are true about analog to digital conversion of voice signals for use in digital telephony networks?()A、The three required steps in the analog to digital conversion are sampling,encoding,and compression.B、The three required steps in th

题目

Which two statements are true about analog to digital conversion of voice signals for use in digital telephony networks?()

  • A、The three required steps in the analog to digital conversion are sampling,encoding,and compression.
  • B、The three required steps in the analog to digital conversion are sampling,quantization,and compression.
  • C、The three required steps in the analog to digital conversion are sampling,quantization,and encoding.
  • D、The output of the sampling process is a pulse code modulation (PCM) signal.
  • E、The output of the sampling process is a pulse amplitude modulation (PAM) signal.

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更多“Which two statements are true about analog to digital conversion of voice signals for use in digital telephony networks?()A、The three required steps in the analog to digital conversion are sampling,encoding,and compression.B、The three required steps in th”相关问题
  • 第1题:

    Digital data can also be represented by (71)signals by use ofa modem. The modem converts a series of binary voltage (72) into an analog signal by encoding the digital data ontoa carrier frequency. The resulting signal occupies a certam spectrum of (73) centered about the carTier and may be propagated acrossa medium suitable for that carrier. The most common modems represent digital data in the voice(74)and hence allow those datato be propagated over ordinary voice-grade (75 )lines At the other end of the line, another modem demodulates the signal to recover the original data

    (71)

    A.analog

    B.digital

    C.Modem

    D.electric


    正确答案:A
    数字数据也可以通过调制解调器用模拟信号来表示。调制解调器把数字数据编码为一种载波频率,从而可以把二进制电压序列转换为模拟信号。产生的信号占用了以某一频率为中心的载波频带,可以通过适合于该载波的介质进行传播。大多数通用的调制解调器表示话音频带的数字数据,因而允许这些数据在通常的话音级电话线路上传播。在线路的另一端,另外一个调制解调器对信号进行解调并恢复原来的数据。

  • 第2题:

    Which of the following describes the roles of devices in a WAN (Choose three.)()。

    A.A CSU/DSU terminates a digital local loop.

    B.A modem terminates a digital local loop.

    C.A CSU/DSU terminates an analog local loop.

    D.A modem terminates an analog local loop.

    E.A router is commonly considered a DTE device.

    F.A router is commonly considered a DCE device.


    参考答案:A, D, E

  • 第3题:

    Which three functions are associated with a Cisco Unified CallManager? ()

    • A、 connects traditional telephony devices to voice over IP infrastructure
    • B、 converts analog signals to digital format
    • C、 performs voice compression
    • D、 performs call processing
    • E、 performs dial plan administration
    • F、 performs signaling and device control

    正确答案:D,E,F

  • 第4题:

    Which two statements are true about the digital audio in a VoIP network? ()

    • A、 Standard encoding techniques create an uncompressed digital data rate of 4000 bps.
    • B、 Standard encoding techniques create an uncompressed digital data rate of 8000 bps.
    • C、 Standard encoding techniques create an uncompressed digital data rate of 64,000 bps.
    • D、 Voice quality is not a concern if compression is not used.
    • E、 Two methods of quantization are linear and logarithmic.
    • F、 Two methods of compression are u-law and a-law.

    正确答案:C,E

  • 第5题:

    What is the difference between a CSU/DSU and a modem?()

    • A、A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line
    • B、A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line
    • C、A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line
    • D、A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line

    正确答案:D

  • 第6题:

    Which three functions can an Integrated Services Router perform in a VoIP network?()

    • A、 voice stream mixing for conference calling
    • B、 voice gateway
    • C、 call admission control
    • D、 analog or digital phone interfaces
    • E、 XML application services
    • F、 large scale dial plan application

    正确答案:B,C,D

  • 第7题:

    When comparing analog display inputs to digital display inputs, which of the following is anadvantage that digital has over analog?()

    • A、Allows for higher brightness
    • B、More crosstalk
    • C、Sustains higher resolutions
    • D、Supports widescreen resolutions

    正确答案:C

  • 第8题:

    多选题
    Which of the following describes the roles of devices in a WAN? (Choose three.)()
    A

    A CSU/DSU terminates a digital local loop.

    B

    A modem terminates a digital local loop.

    C

    A CSU/DSU terminates an analog local loop.

    D

    A modem terminates an analog local loop.

    E

    A router is commonly considered a DTE device.

    F

    A router is commonly considered a DCE device.


    正确答案: F,E
    解析: 暂无解析

  • 第9题:

    多选题
    When a router converts analog signals to digital signals, what three steps are always included in the process?()
    A

    involution

    B

    encoding

    C

    sampling

    D

    quantization

    E

    compression

    F

    companding


    正确答案: E,F
    解析: 暂无解析

  • 第10题:

    单选题
    Which statement is true about the capabilities of a voice gateway router?()
    A

    voice gateways with analog interfaces need a gatekeeper to convert analog signals into digital format before voice is encapsulated into IP packets

    B

    voice gateways need a gatekeeper to interconnect the VoIP networks the PSTN network

    C

    voice gateways with Cisco Unified CallManager Express (CME) can permanently act as a call agent for IP phones

    D

    voice gateways equipped with a DSP module can take the role of the call agent during WAN failure.


    正确答案: D
    解析: 暂无解析

  • 第11题:

    单选题
    What is the difference between a CSU/DSU and a modem?()
    A

    A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line.

    B

    A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line.

    C

    A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line.

    D

    A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.


    正确答案: B
    解析: 暂无解析

  • 第12题:

    单选题
    What is the difference between a CSU/DSU and a modem?()
    A

    A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line

    B

    A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line

    C

    A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line

    D

    A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line


    正确答案: A
    解析: 暂无解析

  • 第13题:

    What is the difference between a CSU/DSU and a modem?()

    A. A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line.

    B. A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line.

    C. A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line.

    D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.


    参考答案:D

  • 第14题:

    Which statement is true about the capabilities of a voice gateway router?()

    • A、voice gateways with analog interfaces need a gatekeeper to convert analog signals into digital format before voice is encapsulated into IP packets
    • B、voice gateways need a gatekeeper to interconnect the VoIP networks the PSTN network
    • C、voice gateways with Cisco Unified CallManager Express (CME) can permanently act as a call agent for IP phones
    • D、voice gateways equipped with a DSP module can take the role of the call agent during WAN failure.

    正确答案:C

  • 第15题:

    What is the term that is used to describe the process of converting a signal from digital to analog?()

    • A、 packetization
    • B、 quantization
    • C、 decoding
    • D、 sampling

    正确答案:C

  • 第16题:

    When a router converts analog signals to digital signals, what three steps are always included in the process?()

    • A、involution
    • B、encoding
    • C、sampling
    • D、quantization
    • E、compression
    • F、companding

    正确答案:B,C,D

  • 第17题:

    Which statement is true about the digital to analog conversion process?()

    • A、the two steps of digital to analog conversion are decompression and reconstruction of the analog signal
    • B、the two steps of digital to analog conversion are decoding and filtering
    • C、the two steps of digital to analog conversion are decompression and filtering of the analog signal
    • D、the two steps of digital to analog conversion are quantization and decoding

    正确答案:B

  • 第18题:

    What are two steps that are taken when a router converts a voice signal from analog to digital form?()

    • A、sampling
    • B、packetization
    • C、quantization
    • D、serialization

    正确答案:A,C

  • 第19题:

    单选题
    Which statement is true about the digital to analog conversion process?()
    A

    the two steps of digital to analog conversion are decompression and reconstruction of the analog signal

    B

    the two steps of digital to analog conversion are decoding and filtering

    C

    the two steps of digital to analog conversion are decompression and filtering of the analog signal

    D

    the two steps of digital to analog conversion are quantization and decoding


    正确答案: C
    解析: 暂无解析

  • 第20题:

    单选题
    What are two steps that are taken when a router converts a voice signal from analog to digital form?()
    A

     sampling

    B

     packetization

    C

     quantization

    D

     serialization


    正确答案: A
    解析: 暂无解析

  • 第21题:

    多选题
    Which three functions are associated with a Cisco Unified CallManager? ()
    A

    connects traditional telephony devices to voice over IP infrastructure

    B

    converts analog signals to digital format

    C

    performs voice compression

    D

    performs call processing

    E

    performs dial plan administration

    F

    performs signaling and device control


    正确答案: B,E
    解析: 暂无解析

  • 第22题:

    多选题
    Which two statements are true about analog to digital conversion of voice signals for use in digital telephony networks?()
    A

    The three required steps in the analog to digital conversion are sampling,encoding,and compression.

    B

    The three required steps in the analog to digital conversion are sampling,quantization,and compression.

    C

    The three required steps in the analog to digital conversion are sampling,quantization,and encoding.

    D

    The output of the sampling process is a pulse code modulation (PCM) signal.

    E

    The output of the sampling process is a pulse amplitude modulation (PAM) signal.


    正确答案: B,E
    解析: 暂无解析

  • 第23题:

    多选题
    Which two statements are true about the digital audio in a VoIP network? ()
    A

    Standard encoding techniques create an uncompressed digital data rate of 4000 bps.

    B

    Standard encoding techniques create an uncompressed digital data rate of 8000 bps.

    C

    Standard encoding techniques create an uncompressed digital data rate of 64,000 bps.

    D

    Voice quality is not a concern if compression is not used.

    E

    Two methods of quantization are linear and logarithmic.

    F

    Two methods of compression are u-law and a-law.


    正确答案: D,E
    解析: 暂无解析