"innivation belt" doesn't seem to really exist in this context in English. Besides, it sounds like some sort of an abdominal stimulation contraption :)))
So, I think it would be to literal a translation.

On the other hand, "innovation hub" is widely used and seems (to me) to be suitable for your context.

For example (there are many), that's how W.dia describes Silicon Valley:
en.wikipedia.org/wiki/Silicon_Valley‎
Silicon Valley is a leading hub and startup ecosystem for high-tech innovation and development, accounting for one-third of all of the venture capital investment ...

Or see this:
cii.oii.ox.ac.uk/what-is-a-tech-innovation-hub-anyway/‎
16 Sep 2014 ... Innovation and entrepreneurship “hubs” and “labs” are all the rage these days. A wide range of actors is convinced that hubs represent a ...