Most digital transmission systems are "self-clocking" in that they derive the bit synchro-nization from the signal itself. To do this, the systems use the transitions between positive and negative...

Most digital transmission systems are "self-clocking" in that they derive the bit synchro-nization from the signal itself. To do this, the systems use the transitions between positive and negative voltage levels. These transitions help define the boundaries of the bit inter-vals. a. The nonreturn-to-zero (NRZ) signaling method transmits a 0 with a + I voltage of duration T, and a 1 with a —1 voltage of duration T. Plot the signal for the sequence n consecutive Is followed by n consecutive Os. Explain why this code has a synchroniza-tion problem. b. In differential coding the sequence of Os and Is induces changes in the polarity of the signal; a binary 0 results in no change in polarity, and a binary 1 results in a change in polarity. Repeat part (a). Does this scheme have a synchronization problem? \

c. The Manchester signaling method transmits a 0 as a + I voltage for T/2 seconds follows by a —I for T/2 seconds; a I is transmitted as a —1 voltage for T/2 seconds follows by a + 1 for T/2 seconds. Repeat part (a) and explain how the synchronization problem has been addressed. What is the cost in bandwidth in going from NRZ to Manchester coding?