MCQ in Digital and Data Communication Networks Part 6 | ECE Board

This is the Multiple Choice Questions Part 6 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.

MCQ Topic Outline included in ECE Board Exam Syllabi

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

Continue Practice Exam Test Questions Part 6 of the Series

⇐ MCQ in Digital and Data Communication Networks Part 5 | ECE Board

Choose the letter of the best answer in each questions.

251. If the active time of the binary pulse is less than 100% of the bit time

A. Non return to zero

B. Bipolar

C. Unipolar

D. Return to zero

252. It is a popular type of line encoding that produces a strong timing component for clock recovery and does not cause wandering

A. Digital biphase

B. diphase

C. Manchester code

D. Any of these

253. Statistical TDMs are also called

A. Intelligent TDMs

B. Asynchronous TDM

C. Stat mux

D. Any of these

254. A chip that combines the codec and filter functions in the same LSI chip

A. Monolithic

B. Combo chip

C. Film IC

D. Hybrid chip

255. It is the basic building block of FDM hierarchy

A. Character channel

B. Broadband channel

C. Message channel

D. Information capacity

256. It is the next higher level in the FDM hierarchy above the basic message channel and consequently is the first multiplexing step for combining message channels

A. Supergroup

B. Group

C. Mastergroup

D. Jumbogroup

257. It is the modulating signal in a communications system

A. Broadband

B. Baseband

C. Carrier

D. Any of these

258. What type of mastergroup that can be further multiplexed and used for higher-capacity microwave radio systems?

A. A600

B. U600

C. L600

D. L400

259. It is essentially the same with FDM, where several signals are transmitted using different carriers, occupying non-overlapping bands of frequency and wavelengths.

A. Time division multiplexing

B. Wave division multiplexing

C. Space division multiplexing

D. Frequency division multiplexing

260. In order to separate channels in the TDM receiver, it is necessary to use

A. AND gates

B. bandpass filters

C. differentiation

D. integration

261. To separate channels in an FDM receiver, it is necessary to use

A. AND gates

B. bandpass filters

C. differentiation

D. integration

262. In FDM, multiple signals

A. transmit at different times

B. share a common bandwidth

C. use multiple channels

D. modulate one another

263. Frequency modulation in FDM usually accomplished with a

A. reactance modulator

B. varactor

C. VCO

D. PLL

264. Which of the following is not a common LAN medium?

A. twin lead

B. twisted pair

C. fiber-optic cable

D. coax

265. A mainframe computer connected to multiple terminals and PCs usually uses which configuration?

A. bus

B. ring

C. star

D. tree

266. How many voice channels are there in supermaster group?

A. 300

B. 900

C. 3600

D. 10800

267. In a PAM/TDM system, keeping the multiplexer and DEMUX channels step with one another is done by a

A. clock recovery circuit

B. sync pulse

C. sampling

D. sequencer

268. It is the process of volume compression before transmission and expansion after detection.

A. pre-emphasis

B. de-emphasis

C. coding

D. companding

269. Which of the following is correct?

A. The bit rate may be greater than the baud rate

B. The baud rate may be greater than the bit rate

C. The bit and baud rate are always the same

D. The bit and baud rates are not related

270. Function of data link protocol that coordinates the rate at which data are transported over a link and generally provides an acknowledgement mechanism that ensures that data are received in the destination.

A. Flow control

B. Line discipline

C. Polling

D. Selection

271. A classification of protocol, which is a discipline for a serial-by-bit information transfer over data communications channel.

A. Message oriented

B. Bit-oriented protocol

C. Clock oriented protocol

D. Asynchronous protocol

272. A LAN device that interconnects two or more device running identical internetwork protocols.

A. Bridges

B. Gateways

C. Switches

D. Routers

273. The magnitude of a quantum in quantization of PCM codes.

A. Maximum decodable voltage

B. Dynamic range

C. Resolution

D. Coding level

274. It comprises of either a single L600 mastergroup or up to three U600 mastergroups

A. Message channel

B. Radio channel

C. Baseband channel

D. Wide channel

275. It is a multiplexing system similar to conventional time-division multiplexing except that it was developed to be used with optical fibers

A. SONET

B. Frame relay

C. ATM

D. X.25

276. Higher order TDM levels are obtained by

A. dividing pulse widths

B. using the a-law

C. using u-law

D. forming supermastergroups

277. Results when the sample exceeds the highest quantization interval

A. Overload distortion

B. Quantization error

C. Quantization noise

D. Granular noise

278. The event which marked the start of the modern computer age was

A. design of the ENIAC computer

B. development of Hollerith code

C. development of the transistor

D. development of disk drives for data storage

279. A forward error correcting code corrects errors by

A. requiring partial transmission of the entire signal

B. requiring retransmission of the entire signal

C. requiring no part of the signal to be transmitted

D. using parity to correct the errors in all cases

280. The carrier used with a BPSK demodulator is

A. Generated by an oscillator

B. The BPSK signal itself

C. Twice the frequency of the transmitted carrier

D. Recovered from the BPSK signal

281. Digital signals

A. do not provide a continuous set of values

B. represent values as discrete steps

C. can utilize decimal or binary systems

D. all of these

282. Each signal in an FDM signal

A. modulates the main carrier

B. modulates the final carrier

C. is mixed with all the others before modulation

D. serves as a subcarrier

283. In digital modulation, if the information signal is digital and the amplitude of the carrier is varied proportional to the information signal.

A. Quaternary Shift Keying (QAM)

B. Phase Shift Keying (PSK)

C. Frequency Shift Keying (FSK)

D. Amplitude Shift Keying (ASK)

284. Slow speed modems

A. FSK

B. BPSK

C. QPSK

D. QAM

285. The data rate for IEEE 802.11b is _____.

A. 10 Mbps

B. 1.544 Mbps

C. 2.048 Mbps

D. 11 Mbps

286. Type of analog companding used in the United States and Japan

A. log-PCM companding

B. A-law companding

C. u-law companding

D. any of these

287. A rule of procedure that defines how data is to be transmitted is called

A. handshake

B. error-detection

C. data specifications

D. protocol

288. A longitudinal redundancy check produces

A. block check character

B. parity bit

C. CRC

D. error correction

289. Multiplexing is the process of

A. Several signal sources transmitting simultaneously to a receiver on common frequency

B. Sending the same signal over multiple channels to multiple destinations

C. Transmitting multiple signals over multiple channels

D. Sending multiple signals simultaneously over a single channel

290. What is the relationship of bit rate and baud in QPSK and 8-PSK?

A. bit rate is greater than baud

B. bit rate is always less than the baud

C. bit rate is never greater than the baud

D. bit rate is slightly less than the baud

291. A common method of achieving carrier recovery for BPSK

A. Trellis code

B. Bandwidth efficiency

C. Squaring loop

D. Carrier recovery

292. What is the relationship of bit rate and baud in FSK and PSK?

A. greater than

B. slightly greater than

C. less than

D. equal

293. The modulation used in FDM telephone system is

A. AM

B. FM

C. SSB

D. PSK

294. In digital modulation, a diagram which is similar to phasor diagram except that the entire phasor is not drawn and only the peaks of the phasor are shown

A. constellation diagram

B. Venn diagram

C. phasor diagram

D. schematic diagram

295. Digital signals may be transmitted over the telephone network if

A. their speed is low enough

B. they are converted to analog first

C. they are ac instead of dc

D. they are digital only

296. Most FDM telemetry system use

A. AM

B. FM

C. SSB

D. PSK

297. In TDM, multiple signals

A. share a common bandwidth

B. modulate subcarriers

C. are sampled at high speeds

D. take turns transmitting

298. It is highly theoretical study of efficient use of bandwidth to propagate information through electronic communications system

A. information capacity

B. data communications

C. information theory

D. information technology

299. Another name for parity is

A. Vertical redundancy check

B. Block check character

C. Longitudinal redundancy check

D. Cyclic redundancy check

300. It is the process of gathering data on some particular phenomenon without the presence of human monitors

A. Telemetry

B. Telecommand

C. Telecommunications

D. Remote control

Questions and Answers in Digital and Data Communication Networks Series

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

Complete List of MCQ in Communications Engineering per topic