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________, 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 : _______ uses twocarriers, onein-phase andthe otherquadrature. A) ASK B) PSK C) FSK D) QAM
Last Answer : QAM
Description : In QAM,both ________ of acarrier frequencyare varied. A) frequencyand amplitude B) phase andfrequency C) amplitudeand phase D) none of the above
Last Answer : amplitudeand phase
Description : The sinusoidal carrier is pulsed so that one of the binary states is represented by a carrier while the other is represented by its absence. A. FSK B. ASK C. PSK D. QAM
Last Answer : B. ASK
Description : Quadrature amplitude modulation(QAM) isa combination of ___________. A) ASK and FSK B) ASK and PSK C) PSK and FSK D) none of the above
Last Answer : ASK and PSK
Description : ASK, PSK, FSK,and QAM are examples of________conversion. A) digital-to-digital B) digital-to-analog C) analog-to-analog D) analog-to-digital
Last Answer : digital-to-analog
Description : DMT is a modulation technique that combineselements of _______ and _______. A) FDM; TDM B) QDM; QAM C) FDM; QAM D) PSK; FSK
Last Answer : FDM; QAM
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 : Modulation in which no signal is present between pulses A. Pulse modulation B. QAM C. PSK D. FSK
Last Answer : A. Pulse modulation
Description : Which of the following is not a digital-to-analogconversion? A) ASK B) PSK C) FSK D) AM
Last Answer : AM
Description : Inan HFC network, the downstream data are modulated using the _______ modulation technique. A) PSK B) QAM C) PCM D) ASK
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
Description : Digital modulation technique used in modems. A. ASK B. PSK C. FSK D. All of these
Last Answer : B. PSK
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 : 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 : If the bit rate for an FSK signal is1200 bps, thebaud rate is ________. A) 300 B) 400 C) 600 D) 1200
Last Answer : 1200
Description : If the baudrate fora 64-QAM signal is 2000, what is the bit rate? A) 300 B) 400 C) 1000 D) 12000
Last Answer : 12000
Description : If the bit rate for a16-QAM signal is 4000 bps, what is the baudrate? A) 300 B) 400 C) 1000 D) 1200
Last Answer : 1000
Description : Inan HFC network, the upstream data are modulated using the _______ modulation technique. A) QAM B) QPSK C) PCM D) ASK
Last Answer : QPSK
Description : In_________ transmission, we send bits oneafter another without startor stop bits or gaps. It is the responsibilityof the receiver togroup the bits. A) synchronous B) asynchronous C) isochronous D) none of the abov
Last Answer : synchronous
Description : Frequencyof failure and network recovery time after a failure are measures of the_______of a network. A) Performance B) Reliability C) Security D) Feasibility
Last Answer : Reliability
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 : If digitaldata rateof 9600 bps is encoded using 8-level phaseshift keying (PSK) method, the modulation rate is A. 1200 bands B. 3200 bands C. 4800 bands D. 9600 bands E. None of the above
Last Answer : 3200 bands
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 pulse modulation technique as the width of a constant amplitude pulse is varied proportional to the amplitude of the analog signal at the time the signal is sampled.
Last Answer : PWM, PLM, PDM
Description : The constellation diagram of16-QAM has ______ dots. A) 4 B) 16 C) 8 D) none of the above
Last Answer : 16
Description : Which of the following is not an analog-to-analog conversion? A) AM B) PM C) FM D) QAM
Description : The transmission signal coding method of TI carrier is called a. Bipolar b. NRZ c. Manchester d. Binary
Last Answer : Bipolar
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 : 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 : 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 : 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 : 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 : What characteristic of a carrier wave is varied in frequency modulation?
Last Answer : Instantaneous frequency.
Description : In a frequency-domain plot, thehorizontal axis measures the________. A) peak amplitude B) frequency C) phase D) slope
Last Answer : frequency
Description : Compare binary ASK, FSK &PSK modulation techniques
Last Answer : Sr. No Parameter Binary ASK Binary FSK Binary PSK 1 Variable Characteristic Amplitude Frequency Phase 2 Maximum bandwidth(Hz) 2fb 5 fb /3 2fb 3 ... 1200 bits/sec Suitable for high bit rates 8 Detection method Envelope Envelope Coherent
Description : The modulation technique used by GSM cellular system A. Phase shift keying B. Frequency shift keying C. Gaussian minimum shift keying D. QAM
Last Answer : C. Gaussian minimum shift keying
Last Answer : Inter-poles are used in both lap and wave wound machines.
Description : In _______, the resources need to bereserved during the setup phase; the resources remain dedicated for the entire durationof data transfer phase until the teardownphase. A) datagram switching B) circuit switching C) frame switching D) none of the above
Last Answer : circuit switching
Description : f the bit rate for an ASK signal is1200 bps, thebaud rate is ________. A) 300 B) 400 C) 600 D) 1200
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 speed of a three-phase squirrel-cage induction-type motor operating in a fixed frequency system is varied by changing the _____________. A. number of phases to the motor B. number of stator poles C. locked rotor current D. resistance of the rotor winding
Last Answer : Answer: B
Description : How is the speed of a 3-phase induction motor varied?
Last Answer : The speed of a normal 3-phase induction motor is a function of the frequency of the supply voltage. Changing the speed of such a motor hence requires building a 3-phase power frequency ... realised by using power MOSFETs (or IGBTs) capable of handling high voltages and fast switching speeds.
Description : An AC circuit has capacitance arranged in series. If the line voltage remains constant, the capacitive reactance value can be varied by changing the _____________. A. line frequency B. resistance C. number of commutating poles D. number of interpoles
Last Answer : Answer: A
Description : It is an average power of a radio transmitter supplied to the antenna transmission line taken during a long sufficient interval of time and compared with the lowest frequency encountered in the modulation ... operating conditions. A. Carrier power B. Rated power C. Mean power D. Peak envelop power
Last Answer : C. Mean power
Description : Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation. A. Carrier power B. Rated power C. Peak envelop power D. Mean power
Last Answer : A. Carrier power
Description : Average power of a radio transmitter supplied to the antenna transmission line by a transmitter during one radio frequency cycle taken under the condition of no modulation. A. Peak envelop power B. Rated power C. Carrier power D. Mean power
Last Answer : C. Carrier power
Description : The product of the power supplied to the antenna and its gain relative to a half-wave dipole in a given direction. A. Peak envelope power B. ERP C. Rated power D. Carrier power’
Last Answer : B. ERP