GCF (Global Certification Forum, the global certification Forum) is a non-profit organization established jointly by carries, terminal manufacturers, test equipment suppliers and testing organizations, aims at ensuring the terminal performance through the independent certification process.

GCF field trial test means to measure the performance, function,  reliability of mobile terminals in real network, including stationary test and routing test. The stationary test mainly includes: network registration, voice service, data service, supplementary services, short message service, SIM related; routing test mainly includes: cell reselection, cell switching and reliability before and after switching of voice service, data service, short message service.