Abstract: The unique frame structure of Open Base Station Architecture Initiative (OBSAI) is well-suited to transmitting data of different wireless standards. In a multi-mode base station built with OBSAI, the baseband-RF interface can effectively screen out the influence of different wireless standards over the data transport link. It can also support multiple wireless standards on a single hardware platform. With such an interface, the Baseband Unit (BBU) and Remote RF Unit (RF) need only be changed to support a new wireless standard, and as long as the rate of the optical interface remains the same, no software, hardware, or logic of other units needs modification.