In the output of a DM speech encoder, the consecutive pulses are of opposite polarity during time interval t₁ $$ \le $$ t $$ \le $$ t₂. This indicates that during this interval

In a PCM system, if the code word length is increased from 6 to 8 bits, the signal to quantization noise ratio improves by the factor

Consider a binary digital communication system with equally likely $$0’s$$ and $$1’s$$. When binary $$0$$ is transmitted the voltage at the detector input can lie between the levels $$-0.25V$$ and $$+0.25V$$ with equal probability when binary $$1$$ is transmitted, the voltage at the detector can have any value between $$0$$and $$1 V$$ with equal probability. If the detector has a threshold of $$2.0V$$ (i.e., if the received signal is greater than $$0.2 V$$, the bit is taken as $$1$$), the average bit error probability is

Choose the correct one from among the alternatives A, B, C, D after matching an item from Group 1 with the most appropriate item in Group 2.

Group
1. FM
2. DM
3. PSK
4. PCM

Group 2
P: Slope overload
Q: $${\mu - law}$$
R: Envelope detector
S: Capture effect
T: Hilbert transform
U: Matched filter