The building will house some 470 antennas and more than 20,000 linear feet of coaxial cable to ensure residents paying $4.3 million and up for apartments will have uninterrupted wireless service. "For this level of building that's top-end in every way, a D.A.S. is just part of the scope of the work," Mr. Gordon said.

Even in buildings that receive wireless signals, residents may experience problems if too many people in the area use the same wireless network at the same time. An in-house wireless network would reduce such capacity issues when call volume is high.

The antenna technology is fairly common in stadiums, hotels and more recently, office towers, said Laura Keyes, a senior account executive at Axispoint Technology Solutions Group, which designs and installs distributed antenna systems. "Residential buildings were later to the game," she said, "but now almost all new construction includes a specification for D.A.S."

Over the last year, the firm has designed 14 distributed antenna systems for new residential and commercial towers, double the number of the previous year. Clients range from the Modern, a 450-unit rental near the entrance to the George Washington Bridge in Fort Lee, N.J., to 432 Park Avenue in Manhattan, which topped out last year at 1,396 feet and holds the title for the tallest residential tower in the Western Hemisphere.

Adding the systems to older apartment buildings is rare, Ms. Keyes said. Once residents are in place, she said, management "doesn't have an incentive to spend the money." The exception is apartment complexes that are undergoing a major renovation. Retrofits are more common in commercial buildings like offices and hospitals, she noted, because of the demand for wireless in such environments.

Several years ago, Time Equities acquired the top 10 floors of 633 Third Avenue, a 40-story tower where Gov. Andrew M. Cuomo has an office. Spotty cellphone coverage had been a problem at the building, and when the governor's lease was up, souping up reception "became a negotiation point in the renewal," said Robert Singer, the director of development for Time Equities. "As you might imagine, we had to quickly get in the game and figure out how to solve it."