In the ATSC 3.0 physical layer standard, a Transmitter Identification (TxID) technology is introduced in order to identify and distinguish each transmitter in single frequency network (SFN) environment. In SFN, it is essential to accurately measure the strength and delay of broadcast signal from each transmitter, and therefore, the network configuration can be appropriately designed and managed by adjusting transmitting power and emission time of each transmitter. In ATSC 3.0, the TxID technology based on RF watermark provides an efficient way to identify each transmitter without turning it on and off. This paper presents TxID detection performance through computer simulation and laboratory test.