A transmitting apparatus, comprising: a baseband packet generator configured to receive a plurality of transport stream packets and generate a baseband packet including a header and a payload; a frame generator configured to generate a frame including the packet; a signal processor configured to process the generated frame; and a transmitter configured to transmit the processed frame, wherein the header comprises a base header which comprises a first field, second field and a third field, wherein the plurality of TS packets comprise at least one of an null TS packet or an non-null TS packet, wherein the first field comprises a value indicating that a packet type of the plurality of TS packets, wherein the second field comprises a value indicating a number of non-null TS packets included in the payload, wherein the third field comprises a first value indicating that there is no an additional header or a second value indicating that there is the additional header, wherein if the third field comprises the second value, the additional header comprises a fourth field, wherein the fourth field comprises a value indicating a number of deleted null TS packets, wherein if the plurality of TS packets comprise at least one null TS packet and an non-null TS packet, the number of deleted null TS packets is a number of null TS packets which precede the non-null TS packet, and wherein the non-null TS packet is included in the payload of the baseband packet. a baseband packet generator configured to receive a plurality of transport stream packets and generate a baseband packet including a header and a payload; a frame generator configured to generate a frame including the packet; a signal processor configured to process the generated frame; and a transmitter configured to transmit the processed frame, wherein the header comprises a base header which comprises a first field, second field and a third field, wherein the plurality of TS packets comprise at least one of an null TS packet or an non-null TS packet, wherein the first field comprises a value indicating that a packet type of the plurality of TS packets, wherein the second field comprises a value indicating a number of non-null TS packets included in the payload, wherein the third field comprises a first value indicating that there is no an additional header or a second value indicating that there is the additional header, wherein if the third field comprises the second value, the additional header comprises a fourth field, wherein the fourth field comprises a value indicating a number of deleted null TS packets, wherein if the plurality of TS packets comprise at least one null TS packet and an non-null TS packet, the number of deleted null TS packets is a number of null TS packets which precede the non-null TS packet, and wherein the non-null TS packet is included in the payload of the baseband packet. wherein the plurality of TS packets comprise at least one of an null TS packet or an non-null TS packet, wherein the first field comprises a value indicating that a packet type of the plurality of TS packets, wherein the second field comprises a value indicating a number of non-null TS packets included in the payload, wherein the third field comprises a first value indicating that there is no an additional header or a second value indicating that there is the additional header, wherein if the third field comprises the second value, the additional header comprises a fourth field, wherein the fourth field comprises a value indicating a number of deleted null TS packets, wherein if the plurality of TS packets comprise at least one null TS packet and an non-null TS packet, the number of deleted null TS packets is a number of null TS packets which precede the non-null TS packet, and wherein the non-null TS packet is included in the payload of the baseband packet.