Boulder, Colorado-based bandwidth provider Zayo Group is expanding its efforts in the small cell market, the company announced today, adding eight markets, including Chicago, Grand Rapids, Houston, Indianapolis, Las Vegas, Louisville, Minneapolis and Phoenix. Small cell networks are used by mobile provider to extend their coverage, and also to boost capacity for cell phone data. Zayo did not say how much it intends to invest in the new small cell networks in those locations, but said they are expected to be complete in the 2015 calendar year. Small cells are being used to boost capacity and speeds for 4G LTE networks, both in indoor and outdoor locations. That technology also is particularly used in high density areas like shopping malls, airports, and other public locations.