1. In polybinary signalling method the present bit of binary sequence is algebraically added with ______ number of previous bits.
a) j
b) 2j
c) j+2
d) j-2
Explanation: In polybinary signalling method the present binary digit of the sequence is formed from the modulo-2 addition of the j-2 preceding digits of the sequence and the present digit.
2. The primary advantage of this method is
a) redistribution of spectral density
b) to favor low frequencies
c) redistribution of spectral density & to favor low frequencies
d) none of the mentioned
Explanation: Each bit can be independently detected in-spite of strong correlation and this provides redistribution of spectral density and also favors low frequencies
3. Source encoding procedure does
a) Sampling
b) Quantization
c) Compression
d) All of the mentioned
Explanation: Source encoding includes a sampling of continuous time signals, quantization of continuous valued signals and compression of those sources.
4. Which signals are function of time?
a) Random signal
b) Deterministic signal
c) Random & Deterministic signal
d) None of the mentioned
Explanation: Deterministic signals are function of time
5. Auto-correlation function is a
a) Even function
b) Odd function
c) Even & Odd function
d) None of the mentioned
Explanation: Auto-correlation function is an even function of time.
6. Shot noise occurs in
a) Transistors
b) Valves
c) Transistors & Valves
d) None of the mentioned
Explanation: Shot noise occurs in both valves and transistors.
7. Source coding reduces
a) Redundancy
b) Average bit rate
c) Redundancy & Average bit rate
d) None of the mentioned
Explanation: Source coding reduces both average bit rate and reduces redundancy.
8. Delay element in delta modulation acts as
a) First order predictor
b) Second order predictor
c) Third order predictor
d) Fourth order predictor
Explanation: Delay element act as first order predictor.
9. Non uniform quantization includes
a) Compression
b) Expansion
c) Compression & Expansion
d) None of the mentioned
Explanation: Compression and expansion give the feature of non uniform quantization
10. The quantization will be finer when
a) Smaller the number of discrete amplitudes
b) Larger the number of discrete amplitudes
c) Does not depend on amplitudes
d) None of the mentioned
Explanation: Larger the number of discrete amplitudes, finer will be the quantization.