Apparatus for transmitting broadcast signals, apparatus for receiving broadcast signals, method for transmitting broadcast signals and method for receiving broadcast signals

摘要

Provided is a method for transmitting a broadcast signal, including: formatting input streams into multiple data pipes (DPs); encoding data of the multiple DPs for each DP; generating at least one signal frames by mapping the encoded data; and modulating data of the generated signal frame using an orthogonal frequency division multiplexing (OFDM) scheme and transmitting a broadcast signal comprising the modulated data of the signal frame, wherein the signal frame includes a preamble, a PLS (Physical Layer Signaling) and EAC (Emergency Alert Channel), the preamble and the PLS include EAC flag information indicating whether there exists EAC in the signal frame, and when the EAC flag information indicates that there exists EAC in the current frame, the PLS further comprises EAC length information, and when the EAC flag information indicates that there doesn't exist EAC in the current frame, the PLS further comprises control information related to EAC transmission.

主权项

1. A method for transmitting a broadcast signal, comprising:
formatting input data into at least one DP (data pipe); encoding data of the DP; generating at least one signal frame by mapping the encoded data; and modulating data of the generated signal frame using an OFDM (orthogonal frequency division multiplexing) scheme and transmitting a broadcast signal comprising the modulated data of the signal frame, wherein the signal frame includes a preamble, a PLS (Physical Layer Signaling), and the data of the DR, the preamble being located at a beginning of the signal frame and the preamble and the PLS carrying signaling data for the signal frame, wherein the preamble includes EAC (Emergency Alert Channel) flag information indicating whether there exists an EAS (Emergency Alert System) message in the signal frame, wherein when the EAC flag information indicates that there exists the EAS message in the current signal frame, the PLS further comprises EAC length information and
when the EAC flag information indicates that there doesn't exist the EAS message in the current signal frame, the PLS further comprises control information related to EAS message transmission, and wherein the control information includes at least one of an EAC code and an EAC counter and a value of the EAC counter is a down counter which indicates a number of signal frames remaining until a next signal frame including the EAS message is received.