PTP Wireless Questions

I realize this isn't a security question, but as theres sooo many people that come here, and theres not another general wireless forum, i would post it here.

A while back i was introduced into running a WISP (wireless ISP) with a few friends, i did alot of documentation but it ended up falling through. One thing i remember is looking up wireless on >5.8ghz (im thinking 30-55GHz).

Basically what's happening is we want to do backups of certain data nightly at another location. A cost for a PTP wireless link from an ISP is outrageous and a fiber link to a data center is even worst.

So my question is, does anyone have any suggestions or comments about a Point-To-Point wireless link in that range? I'm looking at getting 20+mbps actual throughput. The link will be LOS, but i would prefer to stick in something a little less common then 900, 2.4, and 5.8.

Thanks.