Excellent DD! This is definitely an interesting one. It is odd that they have done nothing with filings. I am on the fence as to whether they are hiding something that they don't want disclosed in a filing or they simply do not care. They seem to have great things in the works and plenty of potential though there is very little interest in their stock.
Airspan has certainly changed there direction and appears that they have positioned themselves to fit in a specific role with LightSquared.
The LightSquared / Sprint deal is one I continue to watch.