The present document establishes a standard method for the connection of digital processing equipment (which is producing DAB baseband I/Q signals) and Radio Frequency (RF) modulation equipment in a DAB system. It can also be used to provide access to baseband I/Q signals for test purposes. ETS 300 401 (see Bibliography) established a broadcasting standard for a DAB system. Broadcasters who implement DAB networks require standardized interfaces for the connection of different equipment in the DAB chain. The present document is applicable to DAB channel coding equipment. It describes the characteristics of a suitable interface for the connection of the two major elements of the DAB OFDM generator; the baseband processing equipment and the RF modulator. The interface provides an interconnection between a single source (the baseband processor) and a single destination (the RF modulator). The present document does not cover the generation of the digital I/Q baseband signals. This is covered in ETS 300 401. The digital baseband I/Q interface is unidirectional and does not cover the provision of status nor control information in the reverse direction (i.e. from the modulator back to the baseband processing section of the equipment).