Dish Network said Monday it will offer service to consumers in apartment buildings using a fiber network that can better handle multiple high-definition video signals. The Dish Optical Network is expected to allow customers to receive Dish Network signals over fiber-optic cable instead of via a satellite dish installed at a customer's unit. A group of satellite dishes placed on a roof attached to a fiber line will be able to provide 400 channels of programming to 128 apartments. The Douglas County-based company is the second-largest satellite-TV provider in the nation, with 13.8 million subscribers. The new service will be available this year. Currently, many apartment dwellers can sign up for Dish Network service and receive their own equipment. The new network's capacity to serve 128 units on a single fiber line is more than the company's current system, which uses coaxial cable to provide service to multiple dwellings. According to the Carmel Group, there are 60 million to 70 million apartment dwellers in the U.S. With a system able to provide satellite-TV services to more people at once, Dish has the potential to tap into a large market that is generally served by cable companies, said Jimmy Schaeffler, the Carmel Group's senior multichannel analyst. "It offers (multiple-dwelling-unit) America a form of competition," he said.