Pseudo Random Binary Sequence (PRBS) is essentially a random sequence of binary numbers. So PRBS generator is nothing but random binary number generator. It is 'random' in a sense that the value of an element of the sequence is independent of the values of any of the other elements. It is 'Pseudo' because it is deterministic and after N elements it starts to repeat itself, unlike real random sequences. The implementation of PRBS generator is based on the Linear Feedback Shift Register (LFSR).