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| 1 | Before data can be transmitted, they must be transformed to ________. |
 | A) | periodic signals |
| B) | electromagnetic signals |
| C) | aperiodic signals |
| D) | low-frequency sine waves |
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| 2 | A periodic signal completes one cycle in 0.001 s. What is the frequency? |
| A) | 1 Hz |
| B) | 100 Hz |
| C) | 1 KHz |
| D) | 1 MHz |
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| 3 | In a frequency-domain plot, the horizontal axis measures the ________. |
| A) | peak amplitude |
| B) | frequency |
| C) | phase |
| D) | slope |
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| 4 | In a time-domain plot, the horizontal axis is a measure of ________. |
| A) | signal amplitude |
| B) | frequency |
| C) | phase |
| D) | time |
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| 5 | If the bandwidth of a signal is 5 KHz and the lowest frequency is 52 KHz, what is the highest frequency? |
| A) | 5 KHz |
| B) | 10 KHz |
| C) | 47 KHz |
| D) | 57 KHz |
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| 6 | What is the bandwidth of a signal that ranges from 1 MHz to 4 MHz? |
| A) | 4 MHz |
| B) | 1 KHz |
| C) | 3 MHz |
| D) | none of the above |
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| 7 | As frequency increases, the period ________. |
| A) | decreases |
| B) | increases |
| C) | remains the same |
| D) | doubles |
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| 8 | Given two sine waves A and B, if the frequency of A is twice that of B, then the period of B is ________ that of A. |
| A) | one-half |
| B) | twice |
| C) | the same as |
| D) | indeterminate from |
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| 9 | A sine wave is ________. |
| A) | periodic and continuous |
| B) | aperiodic and continuous |
| C) | periodic and discrete |
| D) | aperiodic and discrete |
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| 10 | If the maximum amplitude of a sine wave is 2 V, the minimum amplitude is ________ V. |
| A) | 2 |
| B) | 1 |
| C) | -2 |
| D) | between -2 and 2 |
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| 11 | A signal is measured at two different points. The power is P1 at the first point and P2 at the second point. The dB is 0. This means ________. |
| A) | P2 is zero |
| B) | P2 equals P1 |
| C) | P2 is much larger than P1 |
| D) | P2 is much smaller than P1 |
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| 12 | ________ is a type of transmission impairment in which the signal loses strength due to the resistance of the transmission medium. |
| A) | Attenuation |
| B) | Distortion |
| C) | Noise |
| D) | Decibel |
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| 13 | ________ is a type of transmission impairment in which the signal loses strength due to the different propagation speeds of each frequency that makes up the signal. |
| A) | Attenuation |
| B) | Distortion |
| C) | Noise |
| D) | Decibel |
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| 14 | ________ is a type of transmission impairment in which an outside source such as crosstalk corrupts a signal. |
| A) | Attenuation |
| B) | Distortion |
| C) | Noise |
| D) | Decibel |
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| 15 | When propagation speed is multiplied by propagation time, we get the ________. |
| A) | throughput |
| B) | wavelength of the signal |
| C) | distortion factor |
| D) | distance a signal or bit has traveled |
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| 16 | Data can be ________. |
| A) | analog |
| B) | digital |
| C) | (a) or (b) |
| D) | none of the above |
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| 17 | _______ data are continuous and take continuous values. |
| A) | analog |
| B) | digital |
| C) | (a) or (b) |
| D) | none of the above |
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| 18 | _______ data have discrete states and take discrete values. |
| A) | Analog |
| B) | Digital |
| C) | (a) or (b) |
| D) | None of the above |
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| 19 | Signals can be ________. |
| A) | analog |
| B) | digital |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 20 | _____ signals can have an infinite number of values in a range. |
| A) | Analog |
| B) | Digital |
| C) | (a) or (b) |
| D) | None of the above |
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| 21 | _______ signals can have only a limited number of values. |
| A) | Analog |
| B) | Digital |
| C) | (a) or (b) |
| D) | None of the above |
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| 22 | Frequency and period are ______. |
| A) | inverse of each other |
| B) | proportional to each other |
| C) | the same |
| D) | none of the above |
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| 23 | ________is the rate of change with respect to time. |
| A) | Amplitude |
| B) | Time |
| C) | Frequency |
| D) | Voltage |
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| 24 | _______ describes the position of the waveform relative to time 0. |
| A) | Frequency |
| B) | Phase |
| C) | Amplitude |
| D) | Voltage |
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| 25 | A sine wave in the ______ domain can be represented by one single spike in the _____ domain. |
| A) | time; frequency |
| B) | frequency; time |
| C) | time; phase |
| D) | phase; time |
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| 26 | A _________ sine wave is not useful in data communications; we need to send a _______ signal. |
| A) | composite; single-frequency |
| B) | single-frequency; composite |
| C) | single-frequency; double-frequency |
| D) | none of the above |
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| 27 | The _____ of a composite signal is the difference between the highest and the lowest frequencies contained in that signal. |
| A) | frequency |
| B) | period |
| C) | bandwidth |
| D) | amplitude |
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| 28 | A(n)_________ signal is a composite analog signal with an infinite bandwidth. |
| A) | digital |
| B) | analog |
| C) | either (a) or (b) |
| D) | neither (a) nor (b) |
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| 29 | Baseband transmission of a digital signal is possible only if we have a ____ channel. |
| A) | low-pass |
| B) | bandpass |
| C) | low rate |
| D) | high rate |
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| 30 | If the available channel is a ____ channel, we cannot send a digital signal directly to the channel. |
| A) | low-pass |
| B) | bandpass |
| C) | low rate |
| D) | high rate |
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| 31 | For a ______ channel, the Nyquist bit rate formula defines the theoretical maximum bit rate. |
| A) | noisy |
| B) | noiseless |
| C) | bandpass |
| D) | low-pass |
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| 32 | For a ______ channel, we need to use the Shannon capacity to find the maximum bit rate. |
| A) | noisy |
| B) | noiseless |
| C) | bandpass |
| D) | low-pass |
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| 33 | _________ can impair a signal. |
| A) | Attenuation |
| B) | Distortion |
| C) | Noise |
| D) | All of the above |
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| 34 | The _________ product defines the number of bits that can fill the link. |
| A) | bandwidth-period |
| B) | frequency-amplitude |
| C) | bandwidth-delay |
| D) | delay-amplitude |