GATE 2023 Communication System Quiz 34

The minimum step-size required for a Delta-Modulator operating at 32 K samples/ sec to track the signal (here u(t) is the unit function)

x(t) = 125t[u(t)–u(t – 1)] + (250 – 125t) [u(t – 1) – u(t – 2)]

so that slope overload is avoided, would be

Four signals g₁(t), g₂(t), g₃(t) and g₄(t) are to be multiplexed and transmitted. g₁(t) and g₄(t) have a bandwidth of 4 kHz, and the remaining two signals have bandwidth of 8 kHz. Each sample requires 8 bit for encoding. What is the minimum transmission bit rate of the system.

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

A delta modulator has the message signal . The minimum sampling frequency required to prevent slope overload distortion, assuming the step size as will be _____kHz.

In a DPCM system, signal m (t) = 2cos² (50t) V is sampled at Nyquist Rate. The samples are processed by a uniform quantizer with step size 0.5. Then the bit rate of the system is ___________bits/sec.