A signal transmitting method, the method comprising: transmitting synchronization signals to a User Equipment, UE, over a predetermined first time-frequency resource; and transmitting a supplementary synchronization signal different from the synchronization signals to the UE over a predetermined second time-frequency resource, characterized in that, both the synchronization signals and the supplementary synchronization signal correspond to the same physical layer cell identifier; wherein before the transmitting the supplementary synchronization signal different from the synchronization signals to the UE over the predetermined second time-frequency resource, the method further comprises: generating a supplementary primary synchronization sequence different from a primary synchronization sequence of the synchronization signals under a predetermined rule, wherein the length of the supplementary primary synchronization sequence is N, and the supplementary primary synchronization sequence corresponds to a physical layer identifier within a physical layer cell identifier group; and generating a supplementary secondary synchronization sequence different from a secondary synchronization sequence of the synchronization signals under a predetermined rule, wherein the length of the supplementary secondary synchronization sequence is N, and the supplementary secondary synchronization sequence corresponds to a physical layer cell identifier group identifier, wherein N represents an integer no less than 62; and the supplementary synchronization signal is generated from the supplementary primary synchronization sequence and the supplementary secondary synchronization sequence, and the physical layer identifier within the physical layer cell identifier group and the physical layer cell identifier group identifier are used for determining the physical layer cell identifier. transmitting synchronization signals to a User Equipment, UE, over a predetermined first time-frequency resource; and transmitting a supplementary synchronization signal different from the synchronization signals to the UE over a predetermined second time-frequency resource, characterized in that, both the synchronization signals and the supplementary synchronization signal correspond to the same physical layer cell identifier; wherein before the transmitting the supplementary synchronization signal different from the synchronization signals to the UE over the predetermined second time-frequency resource, the method further comprises: generating a supplementary primary synchronization sequence different from a primary synchronization sequence of the synchronization signals under a predetermined rule, wherein the length of the supplementary primary synchronization sequence is N, and the supplementary primary synchronization sequence corresponds to a physical layer identifier within a physical layer cell identifier group; and generating a supplementary secondary synchronization sequence different from a secondary synchronization sequence of the synchronization signals under a predetermined rule, wherein the length of the supplementary secondary synchronization sequence is N, and the supplementary secondary synchronization sequence corresponds to a physical layer cell identifier group identifier, wherein N represents an integer no less than 62; and the supplementary synchronization signal is generated from the supplementary primary synchronization sequence and the supplementary secondary synchronization sequence, and the physical layer identifier within the physical layer cell identifier group and the physical layer cell identifier group identifier are used for determining the physical layer cell identifier. generating a supplementary primary synchronization sequence different from a primary synchronization sequence of the synchronization signals under a predetermined rule, wherein the length of the supplementary primary synchronization sequence is N, and the supplementary primary synchronization sequence corresponds to a physical layer identifier within a physical layer cell identifier group; and generating a supplementary secondary synchronization sequence different from a secondary synchronization sequence of the synchronization signals under a predetermined rule, wherein the length of the supplementary secondary synchronization sequence is N, and the supplementary secondary synchronization sequence corresponds to a physical layer cell identifier group identifier, wherein N represents an integer no less than 62; and the supplementary synchronization signal is generated from the supplementary primary synchronization sequence and the supplementary secondary synchronization sequence, and the physical layer identifier within the physical layer cell identifier group and the physical layer cell identifier group identifier are used for determining the physical layer cell identifier.