I really don't see any fuzziness in your image, but I certainly do see what is called "stair-stepping". The reason for this is simply that you don't have enough pixels in your image, so your eye can resolve see individual pixels.
The proper way to improve the situation would be to take your image into Illustrator and use it's "Live Trace / Image Trace" tool. This produces a vector path that can be enlarged to any size without stairstepping or any other artifacts.
I was working on a project in PS and didn't want to close PS right at this moment, so I quickly smoothed out your edges in PS, not in AI. The result is seen below. The only problem is that the smoothing operation slightly rounds sharp corners. If you can't live with this, either wait for someone to come along and do it in AI, or just manually draw in sharper corners wherever needed.
HTH,
Tom M
PS - Don't judge the quality of this from the low rez in-forum preview, click on it and expand it to full rez to inspect carefully.