Question

If the initial pulse of 1000 is fed to shift register, after how many clock pulses does the sequence repeat?

(a) 15

(b) 16

(c) 14

(d) 17

This question was posed to me in unit test.

My question is taken from Pseudo-Noise Sequence and Jamming in portion Spread Spectrum Techniques of Digital Communications

Answer 1

The correct choice is (a) 15

Explanation: If the initial pulse 1000 is given to shift register, the foregoing sequence repeats after 15 clock pulses.