WIRELESS DIGITAL COMMUNICATION

WIRELESS DIGITAL COMMUNICATION

REVISION OF UNIT 1

Multiple Choice

In uniform quantization process

• The step size remains same

• Step size varies according to the values of the input signal

• The quantizer has linear characteristics

• Both a and c are correct

Multiple Choice

The characteristics of compressor in μ-law companding are

• Continuous in nature

• Logarithmic in nature

• Linear in nature

• Discrete in nature

Multiple Choice

In digital transmission, the modulation technique that requires minimum bandwidth is

• Delta modulation

• PCM

• DPCM

• PAM

Multiple Choice

In Differential Pulse Code Modulation techniques, the decoding is performed by

• Accumulator

• Sampler

• PLL

• Quantizer

Multiple Choice

Granular noise occurs when

• Step size is too small

• Step size is too large

• There is interference from the adjacent channel

• Bandwidth is too large

Multiple Choice

The digital modulation scheme in which the step size is not fixed is

• Delta modulation

• Adaptive delta modulation

• DPCM

• PCM

Multiple Choice

In polar RZ format for coding, symbol '0' is represented by

• Zero voltage

• Negative voltage

• Pulse is transmitted for half the duration

• Both b and c are correct

Multiple Choice

In a uni-polar RZ format,

• The waveform has zero value for symbol '0'

• The waveform has A volts for symbol '1'

• The waveform has positive and negative values for '1' and '0' symbol respectively

• Both a and b are correct

Multiple Choice

In Delta Modulation, the bit rate is

• N times the sampling frequency

• N times the modulating frequency

• N times the nyquist criteria

• None of the above

Multiple Select

The Nyquist theorem is

• Relates the conditions in time domain and frequency domain

• Helps in quantization

• Limits the bandwidth requirement

• Both a and c

Multiple Choice

Equalization in digital communication

• Reduces inter symbol interference

• Removes distortion caused due to channel

• Is done using linear filters

• All of the above

Multiple Choice

In Delta modulation,

• One bit per sample is transmitted

• All the coded bits used for sampling are transmitted

• The step size is fixed

• Both a) and c) are correct

Multiple Choice

Polar coding is a technique in which

• 1 is transmitted by a positive pulse and 0 is transmitted by negative pulse

• 1 is transmitted by a positive pulse and 0 is transmitted by zero volts

• Both a & b

• None of the above

Multiple Choice

The quantization will be finer when

• Smaller the number of discrete amplitudes

• Larger the number of discrete amplitudes

• Does not depend on amplitudes

• None of the mentioned

WHICH LINE CODE SCHEME THIS CORESSPOND ?

Poll

IN THE PREVIOUS IMAGE WHICH LINE CODE SCHEME IT DENOTES?

• UNIPOLAR NRZ SCHEME

• POLAR RZ SCHEME

Multiple Choice

WHICH LINE CCODE SCHEME IT CORRESPOND?

• MANCHESTER

• POLAR RZ