Compiler options effect on system-level near field EMI

Abstract

Our previous research result shows that a microcontroller running different machine codes will emit different levels of EMI. This paper considers the EMI behaviors of the same testing program under different compilers or different compiler optimization options who can generate different machine codes for the same C program. The testing program is executed on a time-sharing open-source robot system to mimic practical use case of industrial applications. According to the experiment result, different compilers or different optimization options have large EMI impact for the same C program. The differences may be up to 29 dB at low-frequency bandwidth.