MCQs in Digital and Data Communication Networks Part VII

(Last Updated On: September 10, 2019)

This is the Multiples Choice Questions Part 7 of the Series in Digital and Data Communication Networks as one of the Communications Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Examination Questions in Electronic System and Technologies, Communications Books, Journals and other Communications References.

Online Questions and Answers Topic Outline

• MCQs in Bit and and Binary Transmission
• MCQs in Signaling Rate
• MCQs in Error Probability, Digital Filtering, Switching, Packet Circuit, Vertical Circuit
• MCQs in Open systems Interconnection
• MCQs in Multiplying, Modulation and Synchronization
• MCQs in Pulse Code Modulation, Companding, Encoding, Bandwidth and Signal to Noise Ratio
• MCQs in Delta Modulation, Slope Overload, Adaptive Delta Modulation, Codes and Protocol
• MCQs in Error Detection and Correction, Digital Carrier systems
• MCQs in Frequency Shift Keying, Phase Shift Keying, Differential Phase Shift keying
• MCQs in DC nature of data transmission, loops, Neutral and Polar
• MCQs in Binary transmission and the concept of time
• MCQs in Asynchronous and Synchronous, timing, Distortion, Bits, band, WPM
• MCQs in Data Interface standards, Data input/output devices
• MCQs in Digital Transmission on analog channel, Modulation-demodulation schemes parameters
• MCQs in Circuit conditioning, Modem Applications
• MCQs in Serial and Parallel Transmission

MCQs in Digital and Data Communication Networks Series

Following is the list of multiple choice questions in this brand new series:

Continue Practice Exam Test Questions Part VII of the Series

301. A convenient technique for determining the effects of the degradations introduced into the pulses as they travel to the regenerator.

• A. Standing wave ratio
• B. Eye patterns
• C. Reflection coefficient
• D. Any of these

302. Spread spectrum stations sharing a band are identified by and distinguished from one another

• A. PSN code
• B. Frequency of operation
• C. Clock rate
• D. Modulation type

303. The ASCII code has

• A. 4 bits
• B. 5 bits
• C. 7 bits
• D. 8 bits

304. The first file transfer protocol designed to facilitate transferring data between two personal computers over the public switched telephone network

• A. X modem protocol
• B. Y modem protocol
• C. Z modem protocol
• D. BLAST

305. For a single-channel PCM system with a sample rate of 6000 samples per second and a seven-bit compressed PCM code, what is the line speed?

• A. 21,000 bps
• B. 42,000 bps
• C. 14,000 bps
• D. 12,000 bps

306. It is often used to compare the performance of one digital modulation technique to another

• A. Bandwidth efficiency
• B. Spectral efficiency
• C. Information density
• D. All of these

307. It is the process of extracting a phase-coherent reference carrier from a receiver signal

• A. Phase referencing
• B. Trellis code
• C. Squaring loop
• D. any of these

308. It is the measure of how much information can be propagated through a communication system and is a function of a bandwidth of the transmission line

• A. information theory
• B. information capacity
• C. information technology
• D. digital communications

309. In delta modulation, the modulator is sometimes called _____.

• A. continuous ADC
• B. tracking ADC
• C. variable slope ADC
• D. slope ADC

310. The code which provides for parity checks is

• A. Baudot
• B. ASCII
• C. CCITT-2
• D. EBCDIC

311. Form of multiplexing that constitutes propagating signals from different cables that sre contained within the same trench

• A. Wavelength division multiplexing
• B. Wave division multiplexing
• C. Space division multiplexing
• D. Frequency division multiplexing

312. For an 8-PSK system, operating with an information bit rate of 24 kbps, determine the bandwidth efficiency

• A. 8 bits/cycle
• B. 2 bits/cycle
• C. 3 bits/cycle
• D. 4 bits/cycle

313. Element of a PCM system that periodically samples the analog input signal and converts those samples to a multilevel PAM signal

• A. Bandpass filter
• B. Sample-and-hold circuit
• C. Analog-to-digital converter
• D. Digital-to-analog converter

314. It is the ratio of the average carrier power to the thermal noise power

• A. Signal-to-noise ratio
• B. Noise figure
• C. Noise factor
• D. Carrier-to-noise ratio

315. A form of switching which is hold and forward

• A. Packet switching
• B. Message switching
• C. Circuit switching
• D. Digital switching

316. It can be used to categorize the type of transmission

• A. Duty cycle
• B. Companding
• C. Coding efficiency
• D. Dynamic range

317. Type of multiplexing where multiple sources that originally occupied the same frequency spectrum are each converted to a different frequency band and transmitted simultaneously over a single transmission medium.

• A. FDM
• B. ATM
• C. TDM
• D. Spread spectrum

318. It is a solicitation sent from the primary to a secondary to determine if the secondary has data to transmit

• A. Selection
• B. Polling
• C. Error control
• D. Master control

319. Function of data link control that specifies the means of detecting and correcting transmission errors

• A. Error control
• B. Selection
• C. Protocol
• D. Synchronization

320. The Hartley law states that

• A. the maximum rate of information transmission depends on the channel bandwidth
• B. the maximum rate of information depends on the depth of modulation
• C. redundancy is essential
• D. only binary codes may be used

321. It represents the number of independent symbols that can be carried through a system in a given unit of time.

• A. information theory
• B. information capacity
• C. information technology
• D. digital communications

322. The Shannon-Hartley law

• A. refers to distortion
• B. defines the bandwidth
• C. describes signaling rates
• D. refers to noise

323. The most basic digital symbol used to represent information

• A. bit
• B. baud
• C. bits per second
• D. any of these

324. Function of data link protocol that coordinates hop-to-hop data delivery where a hop maybe a computer, a network controller or a network-connecting device such as router.

• A. Flow control
• B. Error control
• C. Line discipline
• D. Selection

325. Quadrature amplitude modulation is

• A. Amplitude modulation only
• B. QPSK only
• C. AM plus QPSK
• D. AM plus FSK

326. The most common modulation system used for telegraphy is

• A. frequency-shift keying
• B. two-tone modulation
• C. pulse-code modulation
• D. single-tone modulation

327. It is used to encode the minimum amount of speech information necessary to reproduce a perceptible message with a fewer bits that those needed by a conventional encoder/decoder

• A. codec
• B. muldem
• C. vocoders
• D. modem

328. It is the transmission of information in any form from one source to one or more destination

• A. Modulation
• B. Multiplexing
• C. Encoding
• D. Decoding

329. A form of switching which is stored and forward

• A. Packet switching
• B. Message switching
• C. Circuit switching
• D. Digital switching

330. In digital modulation, it is similar to standard amplitude modulation except there is only two amplitudes possible

• A. frequency shift keying
• B. quaternary amplitude modulation
• C. amplitude shift keying
• D. phase shift keying

331. The technique of using modulation and FDM to transmit multiple data channels of a common medium is known as

• A. baseband
• B. broadband
• C. ring
• D. bus

332. Which of the following is not a benefit of companding

• A. minimizes noise
• B. minimizes number of bits
• C. minimizes quantizing error
• D. minimizes signal bandwidth

333. Transmissions from multiple sources occur in the same facility but not at the same time

• A. Time Division Multiplexing
• B. Frequency Division Multiplexing
• C. Wave Division Multiplexing
• D. Space Division Multiplexing

334. A 9600-baud rate signal can pass over the voice grade telephone line if which kind of modulation is used?

• A. BPSK
• B. QPSK
• C. DPSK
• D. QAM

335. Indicate which of the following pulse modulation systems is analog

• A. PCM
• B. PWM
• C. Differential PCM
• D. Delta

336. The modulation system inherently most noise-resistant is

• A. SSB, suppressed carrier
• B. frequency modulation
• C. pulse-position modulation
• D. pulse-code modulation

337. It is simply the number of bits transmitted during one second and expressed in bits per second

• A. baud
• B. bits
• C. bit rate
• D. pulse repetition rate

338. It is the most prevalent encoding technique used for TDM signals

• A. PAM
• B. PLM
• C. PPM
• D. PCM

339. The characters making up the message in a synchronous transmission are collectively referred to as the data

• A. set
• B. sequence
• C. block
• D. collection

340. A virtual circuit which is logically equivalent to a two-point dedicated private-line circuit except slower

• A. Switched Virtual Circuit
• B. Permanent Virtual Circuit
• C. Switched Leased Circuit
• D. Permanent Leased Circuit

341. To a conventional narrowband receiver, a spread spectrum signal appears to be like

• A. Noise
• B. Fading
• C. A jamming signal
• D. An intermittent connection

342. It is a low-quality video transmission for use between non-dedicated subscribers

• A. Digital phone
• B. Picturephone
• C. Cameraphone
• D. Cellphone with camera

343. Pulse code modulation is preferred to PAM because of its

• A. resistance to quantizing error
• B. simplicity
• C. lower cost
• D. superior noise immunity

344. A CRC generator uses which component?

• A. balanced modulator
• B. shift register
• C. binary adder
• D. multiplexer

345. A signaling element is sometimes called

• A. information
• B. data
• C. symbol
• D. intelligence

346. Which of the following words has the correct parity bit? Assume odd parity. The last bit is the parity bit.

• A. 1111111 1
• B. 1100110 1
• C. 0011010 1
• D. 0000000 0

347. It is a digital interface that provides the physical connection to the digital carrier network

• A. Modem
• B. Codec
• C. Muldem
• D. DSU/CSU

348. It is the only digitally encoded modulation technique that is commonly used for digital transmission

• A. PAM
• B. PCM
• C. PLM
• D. PPM

349. The most common circuit used for demodulating binary FSK signals

• A. phase locked loop
• B. Foster-Seeley discriminator
• C. varactor
• D. phase shift method

350. A digital modulation technique also known as “on-off” keying

• A. PSK
• B. FSK
• C. QUAM
• D. OOK

Complete List of MCQs in Communications Engineering per topic