According to the mapping relationship, a mapping relationship of time domain positions is: n2=mod(n1+k2+L,N), herein L is an integer, and types of parameters which may be adopted by L are the same as types of parameters which may be adopted by A and will not be repeated herein. Assuming that L=0, then n2=1 can be determined according to the mapping relationship, that is, the position of the discovery resource element for sending the device discovery signals in the current discovery resource period corresponds to a coordinate ((n2, k2) (n2=0, k2=6).

In accordance with yet still another aspect of the embodiment, still another relationship is recorded. The process of determining the mapping relationship includes: converting positions of the discovery resource elements in the preceding discovery resource period of the current resource period into a position sequence, interleaving the position sequence using the interleaver to obtain a new position sequence, and mapping the obtained position sequence to the discovery resource elements in the current discovery resource period. The interleaver, which may be an interleaver defined by the LTE system, may be designed with reference to LTE protocol 36.212.