so you have a logo with low resolution
here's how to easily fix it if the
document resolution is not high enough
go to image image size and increase it
to let's say in this case thousand by
thousand pixels and hit okay now let's
go to filter blur and then gaussian blur
slowly and gradually increase the blur
to the point where you just cannot see
the pixelation after adding the blur
let's create a curves or a levels
adjustment layer take the rightmost
slider to the left so that the lighter
gray areas become absolutely white and
then take the leftmost slider to the
right so that the dark gray areas become
absolutely black making the edges tack
sharp