A signal transmission method, wherein a first signal and a second signal work at the same time and share an antenna, wherein the first signal and the second signal have a shared band, a radio frequency front-end comprises the antenna, and the antenna is configured to receive and send a mixed signal of the first signal and the second signal; and the method comprises: determining, by a controller, that a priority of the first signal is higher than a priority of the second signal; when the first signal and the second signal work at the same time, determining whether a signal status of the first signal with a higher priority satisfies a service requirement; and if the service requirement is not satisfied, guiding the mixed signal of the first signal and the second signal that is received by the antenna to a processing back-end of the first signal by using a single-pole double-throw switch; or if the service requirement is satisfied, guiding the mixed signal of the first signal and the second signal that is received by the antenna to a power splitter by using the single-pole double-throw switch, and separately transferring the mixed signal of the first signal and the second signal to a processing back-end of the first signal and a processing back-end of the second signal by using the power splitter; wherein the determining whether a signal status of the first signal with a higher priority satisfies a service requirement specifically comprises the following steps: determining whether the first signal is in a receive timeslot, and whether a received signal strength of the first signal is less than a first threshold and/or whether a transmitted signal strength is greater than a second threshold; and if the received signal strength of the first signal is less than the first threshold and/or the transmitted signal strength is greater than the second threshold, and the first signal is in the receive timeslot, determining that the signal status of the first signal with a higher priority does not satisfy the service requirement; or if the received signal strength of the first signal is greater than or equal to the first threshold and/or the transmitted signal strength is less than or equal to the second threshold, or the first signal is not in the receive timeslot, determining that the signal status of the first signal with a higher priority satisfies the service requirement. determining, by a controller, that a priority of the first signal is higher than a priority of the second signal; when the first signal and the second signal work at the same time, determining whether a signal status of the first signal with a higher priority satisfies a service requirement; and if the service requirement is not satisfied, guiding the mixed signal of the first signal and the second signal that is received by the antenna to a processing back-end of the first signal by using a single-pole double-throw switch; or if the service requirement is satisfied, guiding the mixed signal of the first signal and the second signal that is received by the antenna to a power splitter by using the single-pole double-throw switch, and separately transferring the mixed signal of the first signal and the second signal to a processing back-end of the first signal and a processing back-end of the second signal by using the power splitter; wherein the determining whether a signal status of the first signal with a higher priority satisfies a service requirement specifically comprises the following steps: determining whether the first signal is in a receive timeslot, and whether a received signal strength of the first signal is less than a first threshold and/or whether a transmitted signal strength is greater than a second threshold; and if the received signal strength of the first signal is less than the first threshold and/or the transmitted signal strength is greater than the second threshold, and the first signal is in the receive timeslot, determining that the signal status of the first signal with a higher priority does not satisfy the service requirement; or determining whether the first signal is in a receive timeslot, and whether a received signal strength of the first signal is less than a first threshold and/or whether a transmitted signal strength is greater than a second threshold; and if the received signal strength of the first signal is less than the first threshold and/or the transmitted signal strength is greater than the second threshold, and the first signal is in the receive timeslot, determining that the signal status of the first signal with a higher priority does not satisfy the service requirement; or if the received signal strength of the first signal is greater than or equal to the first threshold and/or the transmitted signal strength is less than or equal to the second threshold, or the first signal is not in the receive timeslot, determining that the signal status of the first signal with a higher priority satisfies the service requirement.