Sounds like taps and passives, if it's Vyyo. Which is now Javelin Innovations, sold by Arris. There are no 3GHz actives out there. Cox is only 80% completed with their 1GHz upgrade and they made a hug investment to get it there.
http://www.multichannel.com/article/355481-Maximum_Spectrum.php?rssid=20527&q=cox+1+ghz+upgrade