A binary signal uses 1V over a bit duration to represent a l

A binary signal uses +1V over a bit duration to represent a logic-1, and -1V over a bit duration to represent a logic-0. A 2,000-bit sequence of data is to be represented by such a signal, and it consists of 20 bits having the pattern 10101010101010101010, followed by 1,980 bits that are each random with a 50% probability of being a logic-1 and 50% probability of being a logic-0. Over the 2,000-bit duration of the signal, is the signal/process a stationary random process or a nonstationary random process? Give an explanation to justify your answer. [Partial answer: It is nonstationary.]

Modern Digital & Analog Communication Systems - Lathi and Ding

Solution

Answer

Over the 2000 but duration of the signal, the signal is a non stationay random process because the occurance of high and low is not periodical throughout the signal and is not dependent on time.