Comment by acid_dog

We had a similar problem and used to spray those air freshener sprays towards the source of the smoke whenever we noticed it. The advantage is that those sprays can travel downwards unlike other sources of smell (our neighbor lived below us). And they can be quite strong and linger. And depending on your local laws, you can't just pollute the air with anything you choose, but it's hard to argue against air freshener ("I just wanted my smoke filled balcony to smell nice!"). Whether it worked for us, no, not really, I don't think the neighbor was even sensitive to strong smells.You could hypothetically build some kind of smoke detection system that would automate this, but I think any cigarette smoke detectors won't work better on outside air than your nose.