The understanding of open quantum systems in unbound nuclei is a challenge to the nuclear structure research[1].The continuum coupling effect may lead to a reordering of the shells in such systems[2].A way to study this effect is to compare the level schemes of two mirror nuclei involving an unbound and a bound nucleus such as 16F and 16N[3].Here we report an experiment of studying the level properties of 16F using the resonant elastic scattering with an 15O radioactive beam delivered by the Radioactive Ion Beam Line at Lanzhou(RIBLL)[4].