A method of transmitting signals in a base station of Multiple Input Multiple Output communication system, wherein the base station comprises several antenna elements divided into multiple antenna groups, and the method comprises: B. selecting multiple transmit antenna elements from the several antenna elements to transmit signals, according to working mode of the base station, wherein, the working mode comprises open-loop working mode or closed-loop working mode; wherein, the step B is implemented by the following steps: B1. determining the spatial correlation mode information among the multiple transmit antenna elements according to the working mode; B2. selecting the multiple transmit antenna elements from the several antenna elements to transmit the signal, according to the spatial correlation mode information; wherein when the base station is working under the closed-loop mode, the multiple transmit antenna elements are selected to belong to multiple antenna groups, the spacing between the adjacent antenna elements in one antenna group is the same as the spacing between the adjacent antenna elements in any other antenna group, both spacings do not exceed a fourth predetermined threshold, and different groups are separated by a larger spacing the step B2 is implemented by the following steps: - selecting the multiple antenna groups from the several antenna elements according to the spatial correlation mode information; - transmitting signals using the each antenna group in a polling manner; and the method further comprises the following steps after the step B2: C. receiving feedback information from a mobile station served by the base station; D. determining to transmit the signal using one antenna group of the multiple antenna groups according to the feedback information. B. selecting multiple transmit antenna elements from the several antenna elements to transmit signals, according to working mode of the base station, wherein, the working mode comprises open-loop working mode or closed-loop working mode; wherein, the step B is implemented by the following steps: B1. determining the spatial correlation mode information among the multiple transmit antenna elements according to the working mode; B2. selecting the multiple transmit antenna elements from the several antenna elements to transmit the signal, according to the spatial correlation mode information; wherein when the base station is working under the closed-loop mode, the multiple transmit antenna elements are selected to belong to multiple antenna groups, the spacing between the adjacent antenna elements in one antenna group is the same as the spacing between the adjacent antenna elements in any other antenna group, both spacings do not exceed a fourth predetermined threshold, and different groups are separated by a larger spacing the step B2 is implemented by the following steps: - selecting the multiple antenna groups from the several antenna elements according to the spatial correlation mode information; - transmitting signals using the each antenna group in a polling manner; B1. determining the spatial correlation mode information among the multiple transmit antenna elements according to the working mode; B2. selecting the multiple transmit antenna elements from the several antenna elements to transmit the signal, according to the spatial correlation mode information; - selecting the multiple antenna groups from the several antenna elements according to the spatial correlation mode information; - transmitting signals using the each antenna group in a polling manner; C. receiving feedback information from a mobile station served by the base station; D. determining to transmit the signal using one antenna group of the multiple antenna groups according to the feedback information.