The invention discloses a signal processing method, a base station and a terminal. The signal processing method comprises the following steps: presetting a sub-frame structure, wherein the sub-frame structure at least comprises a first time slot and a second time slot, the first time slot is used for sending a downlink signal, or is idle, or is switched to receive an uplink signal and schedule the transmission of the uplink signal, or not schedule the transmission of the uplink signal, or is switched to only receive and measure other signals without scheduling the signal reception of the uplink signal, and the second time slot is used for receiving the uplink signal and scheduling the transmission of the uplink signal, or is idle, or is switched to only measure the signal without scheduling the signal reception of the uplink signal; and receiving and sending signals by the base station based on the set sub-frame structure. By adopting the method disclosed by the invention, the use fairness of an unauthorized carrier frequency spectrum is improved, so that the unauthorized carrier frequency spectrum is effectively used.