Q1.
a) By using Differential Manchester encoding scheme, draw the time versus amplitude graphs for the bit stream 0101101001.
b) In a digital system, 8 input links are multiplexed by using STDM. Each input source is making 1024 bits per second. Each frame comprises 8 bits from each source and adds 1 bit as a framing bit. Calculate the number of frames transmitted per second and the data capacity of the link.
c) If binary signal is sent over the 3-kHz channel whose signal-to-noise ratio is 20 dB. Then find out the maximum achievable data rate?
Q2.
a) The FM radio transmission bandwidth is 20MHz with frequency ranging from 88MHz to 108MHz. The FM musical channel needs a bandwidth of 50 KHz only. It introduces a guard band of 5 KHz among the channels. Calculate the maximum number of FM music channels which are possible.
b) A channel consists of a bit rate of 4 kbs and a propagation delay of 20 milliseconds. For what range of frame size does stop-and-wait give an effectiveness of at least 50%?
c) Calculate the CRC for a 8-bit sequence 10100001 and a divisor of x3 + 1.