Description : The _________ product defines the number ofbits that can fill the link. A) bandwidth-period B) frequency-amplitude C) bandwidth-delay D) delay-amplitude
Last Answer : bandwidth-delay
Description : A(n)_________ signal is a composite analogsignal with an infinite bandwidth. A) digital B) analog C) either (a)or (b) D) neither (a) nor (b
Last Answer : digital
Description : If the bandwidth of a signal is 5 KHz and thelowest frequency is 52 KHz, what is the highest frequency? A) 5 KHz B) 10 KHz C) 47 KHz D) 57 KHz
Last Answer : 57 KHz
Description : _________ utilization is the useof availablebandwidthto achieve specificgoals. A) Frequency B) Bandwidth C) Amplitude D) None of the abov
Last Answer : Bandwidth
Description : The Nyquist theorem specifies the minimum samplingrate to be_______. A) equal to the lowest frequency of asignal B) equal to the highest frequency ofa signal C) twice thebandwidth of a signal D) twice thehighest frequencyof a signal
Last Answer : twice thehighest frequencyof a signal
Description : It indicates what signal frequencies can be propagated through a given distance of fiber cable. ∙ A. Bandwidth Distance Product ∙ B. Pulse width dispersion ∙ C. Rise time ∙ D. Cutoff frequency
Last Answer : A. Bandwidth Distance Product
Description : The _______ technique uses M different carrier frequencies that are modulated by the source signal. At one moment, the sign modulates one carrier frequency; at the next moment, thesignal modulates another carrier frequency. A) FDM B) DSSS C) FHSS D) TDM
Last Answer : FHSS
Description : If the frequency spectrum of a signal has a bandwidth of500 Hz with thehighest frequency at 600 Hz, what shouldbe the samplingrate, according to the Nyquist theorem? A) 200 samples/s B) 500 samples/s C) 1000 samples/s D) 1200 samples/s
Last Answer : 1200 samples/s
Description : In_______, the peakamplitude of one signal level is 0; the other is thesame as the amplitude of the carrier frequency. A) PSK B) OOK C) FSK D) none of the above
Last Answer : OOK
Description : In_____ transmission, the frequency of the carrier signal is modulated to follow the changing voltage level (amplitude)of the modulating signal. The peak amplitude and phase of the carrier signal remainconstant,but as ... of thecarrier changes correspondingly. A) AM B) PM C) FM D) none of the above
Last Answer : FM
Description : In________, the phase of thecarrier is varied to represent two or more different signal elements. Both peak amplitude and frequency remain constant. A) ASK B) PSK C) FSK D) QAM
Last Answer : PSK
Description : In________, the amplitude of the carrier signal is varied to create signal elements. Both frequency and phase remainconstant. A) ASK B) PSK C) FSK D) QAM
Last Answer : ASK
Description : In a time-domain plot, the horizontal axis is a measure of ________. A) signal amplitude B) frequency C) phase D) time
Last Answer : time
Description : Bits can be sent over guided and unguided media as analog signal by ___________ a. digital modulation b. amplitude modulation c. frequency modulation d. phase modulation
Last Answer : a. digital modulation
Description : The absolute value of a signal's highest intensity is called………. A. Peak Amplitude B. Frequency C. Phase D. Both a and c
Last Answer : A. Peak Amplitude
Description : . The _____of errors is more difficult than the ______. A) correction; detection B) detection; correction C) creation; correction D) creation;detection
Last Answer : correction; detection
Description : A 1 Mhz carrier is amplitude modulated by a pure 200-Hz audio test tone. Which of the following combinations of frequencies represent the total content of the AM signal? A. 1 MHz and 200 Hz B. 1 MHz and 1000.2 kHz C. 999.8 kHz, 1000 kHz, and 1000.2 kHz D. 999.8 kHz and 1000.2 kHz
Last Answer : C. 999.8 kHz, 1000 kHz, and 1000.2 kHz
Description : Suppose a digitized voice channel is made by digitizing 8 kHz bandwidth analog voice signal. It is required to sample the signal at twice the highest frequency (two samples per hertz). What is the bit rate required, if it ... sample requires 8 bits? (A) 32 kbps (B) 64 kbps (C) 128 kbps (D) 256 kbps
Last Answer : (C) 128 kbps
Description : The term modem is a composite word that refers to the two functional entities that make up the device: asignal _______ and a signal _______. A) modulator; demodulator B) demodulator; modulator C) modern;demo D) none of the above
Last Answer : modulator; demodulator
Description : Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference
Last Answer : C. Out of the band
Description : What is the bandwidth ofa signal that ranges from 1 MHz to4 MHz? A) 4 MHz B) 1 KHz C) 3 MHz D) none of the above
Last Answer : 3 MHz
Description : Variation in amplitude or frequency of carrier wave is called A. amplitude modulation B. frequency modulation C. modulation D. bandwidth
Last Answer : modulation
Description : Given an AM radio signal with abandwidth of10 KHzand the highest-frequency component at 705 KHz, what is the frequency of the carrier signal? A) 700 KHz B) 705 KHz C) 710 KHz D) Cannot bedetermined from giveninformation
Last Answer : 700 KHz
Description : The distance a simple signal can travel in one period is called ………… A. Wavelength B. propagation speed C. Frequency D. both a and b
Last Answer : A. Wavelength
Description : In_____ transmission, thephaseof the carrier signal is modulated to follow the changingvoltage level (amplitude) of the modulating signal. A) AM B) PM C) FM D) none of the above
Last Answer : PM
Description : In_____ transmission, thecarrier signal is modulated so that its amplitude varies with the changing amplitudes of the modulating signal. A) AM B) PM C) FM D) none of the above
Last Answer : AM
Description : 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
Last Answer : single-frequency; composite
Description : While measuring frequency response, as the signal generator approaches the lowest and highest frequency the recorder can effectively record, the VTVM reading drops to less than - 3 dB. What does this indicate?
Last Answer : The upper and lower limits of the frequency response specification for that tape recorder.
Description : In________, the available bandwidth is divided into frequency bands. A) FDMA B) TDMA C) CDMA D) none of the above
Last Answer : TDMA
Description : _______ describes the position of the waveform relative to time 0. A) Frequency B) Phase C) Amplitude D) Voltage
Last Answer : Phase
Description : _______is the rateof change with respect totime. A) Amplitude B) Time C) Frequency D) Voltage
Last Answer : Time
Description : In a frequency-domain plot, thehorizontal axis measures the________. A) peak amplitude B) frequency C) phase D) slope
Last Answer : frequency
Description : What is the method of diversity reception where the signal is transmitted on 2 different frequencies over the same path? A. Quadruple B. Frequency C. Polarization D. Space
Last Answer : B. Frequency
Description : What type of transmission is radiated from an aircraft’s radio altimeter antenna? A. An amplitude modulated continuous wave B. A pulse position modulated UHF signal C. A differential phase shift keyed UHF signal D. A frequency modulated continuous wave
Last Answer : D. A frequency modulated continuous wave
Description : A carrier signal has ______. A. Constant peak amplitude B. The information C. Frequency range 20-20000 Hz D. A varying amplitude
Last Answer : A. Constant peak amplitude
Description : Amplitude of modulated wave is in phase with A. output B. system C. frequency D. signal
Last Answer : signal
Description : On oscilloscope screen for dynamic measurement, lissajous diagram is normally used to determine the __________ of the input signal. (A) Frequency (B) Amplitude (C) Damping (D) None of these
Last Answer : (A) Frequency
Description : A 4 GHz carrier is amplitude modulated by a low-pass signal of maximum cut off frequency 1 MHz. lf this signal is to be ideally sampled, the minimum sampling frequency should be nearly
Last Answer : A 4 GHz carrier is amplitude modulated by a low-pass signal of maximum cut off frequency 1 MHz. lf this signal is to be ideally sampled, the minimum sampling frequency should be nearly 4 Ghz
Description : Receiver bandwidth is defined as those frequencies spread between what two points of the receiver response curve?
Last Answer : Half-power points.
Description : For AM, fc =500kHz , fm = 5 kHz Determine: (i) Upper and lower sideband frequencies (ii) Bandwidth
Last Answer : Given data fc = 500KHz , fm = 5KHz USB =fc+fm USB = 500+5 =505 KHz. LSB =fc – fm LSB = 500 – 5 =495 KHz Bandwidth = 2fm . = 2* 5 =10 KHz
Description : Compare PAM, PWM, and PPM on the basis of i. Variable characteristics ii. Bandwidth iii. Information contained in iv. Transmitted power
Last Answer : Compare PAM, PWM, and PPM on the basis of i. Variable characteristics ii. Bandwidth iii. Information contained in iv. Transmitted power
Description : With a single modulating tone, what is the amplitude of the sideband frequencies at 100-percent modulation?
Last Answer : One-half the amplitude of the carrier.
Description : Define: 1)Frequency 2)Bandwidth 3)Wavelength 4)Time period
Last Answer : Frequency: Frequency is the number of cycles per second. Bandwidth: A range of frequencies within a given band, in particular that used for transmitting a signal. Wavelength: Wavelength can be defined as ... for one complete cycle of vibration to pass a given point. OR Time period=1/frequency
Description : Which multiplexing technique shifts each signal to a different carrier frequency? A) FDM B) TDM C) Both (a)and (b) D) None of the above
Last Answer : FDM
Description : A constellation diagram shows us the __________ of a signal element, particularly when we areusing twocarriers (one in-phase and one quadrature). A) amplitudeand phase B) amplitudeand frequency C) frequencyand phase D) none of the above
Last Answer : amplitudeand phase
Description : ________ is a typeof 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
Last Answer : Distortion
Description : Carrier is A. One or more conductors that serve as a common connection for a related group of devices B. a continuous frequency capableof being modulated or impressed witha second signal C. ... that provides a data communications service among stations attached tothe network E. None of the above
Last Answer : a continuous frequency capableof being modulated or impressed witha second signa
Description : Contention is A. One or more conductors that serve as a common connection for a related group of devices B. a continuous frequency capableof being modulated or impressed witha second signal C. ... that provides a data communications service among stations attached tothe network E. None of the above
Last Answer : the condition whentwo or more stations attempt to use the same channel at the same time
Description : The signal which has infinitely many levels of intensity over a period of time is called ……… A. digital signal B. analog signal C. both a and b D. sound signal
Last Answer : A. digital signal
Description : The number of cycles per unit time is called _________ A. Period B. Frequency C. Amplitude D. Wavelength