摘要：As a flexible auxiliary heating method,the electron cyclotron resonance heating（ECRH） has been widely used in many tokamaks and also will be applied for the J-TEXT *** meet requirements of protection and fault analysis for the ECRH system on J-TEXT,signals of gyrotrons such as the cathode voltage and current,the anode voltage and current,etc should be transmitted to the control and data acquisition *** the high voltage environment of gyrotrons,isolation transmission module based on FPGA and optical fiber communication has been designed and *** test results indicate that the designed module has strong anti-noise ability,low error rate and high transmission *** delay of the module is no more than 5 μs which can fulfill the requirements.