Description : A theory that establishes the minimum sampling rate that can be used for a given PCM systems.
Last Answer : Nyquist sampling theorem
Description : The most common method used for sampling voice signals in PCM systems.
Last Answer : flat top sampling
Description : Data rate at which serial PCM bits are clocked out of the PCM encoder onto the transmission line.
Last Answer : line speed
Description : The result whenever the sampling rate is less than twice the highest audio frequency.
Last Answer : alias
Description : An integrated circuit that performs the PCM encoding and decoding functions
Last Answer : Codec
Description : Involves compression in the transmitter after the input sample has been converted to a linear PCM code and then expansion in the receiver prior to PCM coding:
Last Answer : Digital companding
Description : The PCM code for each channel occupies a fixed time slot called:
Last Answer : Epoch
Description : The main advantage of DM over PCM is:
Last Answer : simple circuit
Description : In PCM, it converts the PAM sampled to parallel PCM codes
Last Answer : Analog-to-Digital converter
Description : Type of PCM which is designed to take advantage of the sample-to-sample redundancies in the typical speech waveform
Last Answer : Differential PCM
Description : Numerical indication of how efficiently a PCM code is utilized
Last Answer : Coding efficiency
Description : Used for transmission of PCM encoded time – division multiplexed digital signal.
Last Answer : T carriers
Description : What is a device that provides a method of sampling energy from within a waveguide for measurement or use in another circuit?
Last Answer : Directional Coupler
Description : Sampling technique that when the tops of the sample pulses retain their natural shape during the sample interva
Last Answer : natural sampling
Description : 12 voice channels are sampled at 8000 sampling rate and encoded into 8 bit PCM word. Determine the rate of the data stream. a. 354 kbps b. 750 kbps c. 768 kbps d. 640 kbps
Last Answer : c. 768 kbps
Description : ECE Board Exam March 1996 According to the Nyquist theorem, the sampling rate that can be used in a PCM system is ________ the highest audio frequency. A. once B. eight times C. twice D. thrice
Last Answer : C. twice
Description : It is the ratio of the transmission bit rate to the minimum bandwidth required for a particular modulation scheme
Last Answer : Bandwidth efficiency, Information density, or Spectral efficiency
Description : 10) A valid study: A)portrays the population being studied B)establishes a casual relationship between variables C)uses random sampling D)verifies expected results E)measures what it is supposed to
Last Answer : E)measures what it is supposed to
Description : Steps to follow to produce PCM signal. A. Quantizing, sampling, and coding B. Sampling, quantizing, and coding C. Sampling, coding and quantizing D. Coding, quantizing and coding
Last Answer : B. Sampling, quantizing, and coding
Description : The first step in PCM is ________. A) quantization B) modulation C) sampling D) none of the above
Last Answer : sampling
Description : The most common technique to change an analog signal to digitaldata is called __________. A) PAL B) PCM C) sampling D) none of the abov
Last Answer : PCM
Description : Choosing a discrete value that is near but not exactly at the analog signal level leads to a) PCM error b) Quantization error c) PAM error d) Sampling error
Last Answer : b) Quantization error
Description : The signals which are obtained by encoding each quantized signal into a digital word is called as a) PAM signal b) PCM signal c) FM signal d) Sampling and quantization
Last Answer : b) PCM signal
Description : What is the type of mastergroup used for low – capacity microwave systems?
Last Answer : L600
Description : What distinguishes digital radio systems from conventional analog communications system?
Last Answer : the nature of the modulating signal
Description : In communication systems the frequency range used for voice is:
Last Answer : 300 Hz to 3800 Hz
Description : FDM telephone systems accommodate many channels by:
Last Answer : Using multiple levels of multiplexing
Description : means to prove the identity of the entity that tries to access the system's resources.
Last Answer : Entity authentication
Description : 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
Last Answer : vocoders
Description : The reason a CSMA/CD network has a minimum length for packets is:
Last Answer : to make sure all other nodes hear a collision in progress
Description : The minimum optical power a light detector can receive and still produce a usable electrical output signal.
Last Answer : light sensitivity
Description : The upper pulse rate and information carrying capacity of a cable is limited by:
Last Answer : modal dispersion
Description : Picture frames are repeated at the rate of ___ per second
Last Answer : . 30
Last Answer : 30
Description : For the 16-PSK and a transmission system with a 10kHz bandwidth, determine the maximum bit rate
Last Answer : 40,000 bps
Description : Rate of change of a signal on a transmission medium after encoding and modulation have occurred
Last Answer : baud rate
Description : It is the symmetrical expectation of the bit error rate in the system.
Last Answer : probability of errors
Description : n T1, it is equal to the reciprocal of the sample rate
Last Answer : Frame time
Description : In the ________ traffic model, the rate of the data flow changes in time, with the changes smooth instead of sudden and sharp.
Last Answer : variable bit rate
Description : The ________ is a function of three values: average data rate, peak data rate, and maximum burst size.
Last Answer : Effective bandwidth
Description : The range of wavelength values that a given photodiode will respond.
Last Answer : spectral response
Description : It is the procedure used to decide which device has the permission to transmit at any given time.
Last Answer : Line control
Description : ____ is a dynamic mapping protocol in which a physical address is found for a given logical address
Last Answer : ARP
Description : The ____ layer establishes, maintains, and synchronizes the interaction between communicating systems. a. network b. transport c. session d. presentation
Last Answer : c. session
Description : Point out the wrong statement. a) Distributed transaction systems such as internetworks or cloud computing systems magnify the difficulties faced by identity management systems b) Services that provide digital ... a domain as belonging to a set of assigned addresses d) None of the mentioned
Last Answer : IDaaS Server establishes the identity of a domain as belonging to a set of assigned addresses
Description : The analog signal needs to be sampled at a minimum sampling rate of: (A) 2fs (B) 1/(2fs) (C) fs/2 (D) 2/fs
Last Answer : (A) 2fs
Description : ________ is the method of encoding audio signals used in US standard 1544 kbit/s 24 channel PCM systems. A. Shannon’s law B. A-law C. Newton’s law D. Mu-law
Last Answer : D. Mu-law
Description : What is the reason why companding is employed in PCM systems? A. To overcome impulse noise in PCM receivers B. To allow amplitude limiting in the receivers C. To solve quantizing noise problem D. To protect small signals in PCM from quantizing distortion
Last Answer : D. To protect small signals in PCM from quantizing distortion
Description : ECE Board Exam March 1996 Which of the following pulse modulation systems is analog? A. Delta B. Differential PCM C. PWM D. PCM
Last Answer : C. PWM