How do I repeat elements individually in a row

I have a matrix of several thousand rows each of which is 16 bits representing an integer. In order to simulate 3,1 error correction I have to replicate each bit 3 times. I am currently doing this using for loops, I have read about kron and repmat and they seem that they would be more efficient for this but I can't figure out how to use them properly to do it.

Small example

1111 becomes 111 111 111 111 (without spaces they are there for clarification)

0000 becomes 000 000 000 000

1010 becomes 111 000 111 000

Answer 1

[Dina Irofti]

   a = [1 0 1 0] % or a = [1 1 1 1] or a = [0 0 0 0]
   b = [1 1 1]
   kron(a,b)

[Josh]

That does the trick rather nicely. Thank you for the very quick answer.