Method and apparatus of data transmission and reception in a digital broadcasting system and system thereof

A method and an apparatus of data transmission and reception in a digital broadcasting system and a system thereof are provided to stably enhance detection performance by using an orthogonal signal set when transmitting a TII(Transmitter Identification Indicator) in the digital broadcasting system. A method of data transmission in a digital broadcasting system includes the steps of: framing input bit information by a predetermined bit unit(703); mapping the framed data into a TII by using a predetermined number of orthogonal sets(705); and modulating the TII into an OFDM(Orthogonal Frequency Division Multiplexing) symbol to transmit the OFDM symbol(707).