Spatial field digital modulation (SFDM) communication system is a special index modulation (IM) technique with low hardware complexity and physical layer security potential. However, the deployment of the SFDM system is always complicated and time-consuming. To solve the problems, an adaptive SFDM system without phase measurement is proposed and implemented in this paper. We design a system architecture fit for self-adjustment and propose the corresponding adaptive algorithm. The state isolation and the BER performance are measured under an indoor channel, which verifies its validity.