1. A method for an aperiodic sounding reference signal (SRS) in a user equipment, comprising the following steps:Step A: receiving, by the user equipment, a higher layer signaling, wherein the higher layer signaling comprises L sets of configuration information, and one set of the L sets of configuration information comprising a configuration index and a frequency band;
Step B: receiving a downlink signaling, and the downlink signaling comprises a first index; and
Step C: transmitting a target SRS on a frequency band of a first configuration information, wherein the first configuration information is the one set of the L sets of configuration information with the configuration index equal to the first index in the L sets of configuration information;
wherein the downlink signaling is a physical layer signaling, frequency bands of the L sets of the configuration information are deployed on an unlicensed spectrum, configuration indexes of the L sets of configuration information are unique, configuration indexes are an integer, and the L is a positive integer.