Data transmission method, data transmission device, data transmission system and terminal

The invention provides a data transmission method, a data transmission device, a data transmission system and a terminal. The method comprises the steps of for a site station covered by both a broadband community and a narrowband community at the same time, simultaneously obtaining the information of the broadband community and the information of the narrowband community when user equipment (UE) is accessed to the site station; and flexibly receiving and transmitting data by utilizing the resource of the broadband community or the resource of the narrowband community. According to the invention, the problem in the prior art that the UE cannot flexibly select the resource of the broadband community or the resource of the narrowband community for data transmission can be solved.