 To the receiver, a signal from a single-frequency network appears as a single broadcast with strong multipath interference; in the worst case, it is detected as a main signal and a reflection both of equal strength as signals arrive from multiple transmitters to the same intermediate location at slightly different times.The ATSC standard used for digital television in North America, unlike the DVB-T standard in Europe and other nations, uses 8VSB instead of OFDM—a modulation which allowed a station to transmit at lower peak power levels, but which historically has been far inferior in handling multipath reflections and RF interference.The first widespread commercial deployment of US ATSC digital television began in 1998, with the first early adopters being stations in the largest markets (including New York city, served by transmitters atop the World Trade Center).