Patent ID: 10237590

Abstract:
A method is provided for transmitting broadcast signals. Service data is encoded. The encoded service data is mapped to symbols onto constellations. Data cells are frequency interleaved in a symbol among the symbols in at least one frame unit using an interleaving sequence. The interleaving sequence is generated based on a main interleaving-sequence and a symbol offset value. The interleaving sequence is generated by operating the main interleaving-sequence with the symbol offset value. The data cells are included in the symbol with a symbol index and a frame unit with a frame unit index. The frequency interleaving of the data cells operates on a frame basis. The frequency interleaving of the data cells is reset when a first frame unit is changed to a second frame unit. Data is modulated in the at least one frame unit by an Orthogonal Frequency Division Multiplexing (OFDM) scheme. The broadcast signals carrying the modulated data are transmitted.