Ion reports successful test for single frequency network transmission


Ion Media Networks announced the completion of successful testing of the Richland Towers DTV single frequency network ("SFN") distributed transmission ("DTx") network for the NYC market.  The initiative demonstrated that single-frequency networks offer digital signal coverage equal or superior to the traditional "one-big-tower" transmission approach. "Single frequency networks" or "distributed transmission" refers to an approach where a number of low-power transmitters are utilized to carry all television signals, each on its consistent allocated frequency, to all areas within a marketplace, including those areas that may have topographical obstacles preventing it from being able to receive the digital TV signals from a master tower.  Such a group of transmission sites typically includes low power technology making it less costly to build and operate than the traditional approach of erecting one major transmission antenna per market. The system presents the potential for utilization of broadcasters’ full digital bandwidth and significant opportunities for mobile digital television broadcasting.

The Richland DTx single frequency network consists of a main, high-powered "hub" site in West Orange, N.J., providing coverage to most of the market area; and five low-power DTxT sites that serve the remainder of the area.  Multiple rounds of testing were conducted at the main West Orange site and a transmitter site at 4 Times Square in Manhattan.  The test teams obtained field measurements from the two sites and compared them to measurements taken from five stations transmitting from the Empire State Building.  Field strength, signal quality, reception and all other parameters for the DTx network were comparable to or better than those from the Empire State stations.  The test results are being made available to other interested broadcasters. In anticipation of the 2009 switchover to digital television, the Richland Towers tests provide important proof of concept for capabilities and value of the DTx network for broadcasters.  In addition, the network is decentralized with key sites located outside the midtown and downtown Manhattan areas, and provides potential for expansion.