Effectiveness of Forward Error Corrections Over Different Wired Communication Channels in Harsh Electromagnetic Environments

Abstract

This paper presents the effectiveness of several forward error corrections in a harsh electromagnetic environment. A harsh electromagnetic environment consists of many reflections and unknowns which could negatively impact the functioning of the operational equipment or systems therein. Accordingly, four printed circuit boards with varying EMC designs are considered to emulate four single-trace communication channels. In addition, based upon the reflective characteristics of harsh electromagnetic environments, a Vibrating Intrinsic Reverberation Chamber is used to produce such an environment. It is found that in such a complex environment, with poor EMC-aware design, the reliability of the data transmission can be substantially decreased. A good EMC-aware design provides far better electromagnetic resiliency under similar conditions. Nevertheless, this design still can be affected under harsher electromagnetic environments. Furthermore, the results show that forward error corrections are able to significantly improve the electromagnetic resiliency of the communication channels. However, forward error corrections are not perfect. There are cases that a code word can get corrupted and turn into another valid code word. This type of error results in undetected corrupted data and is considered as the Achilles' heel of forward error corrections. Therefore, it can be concluded that even with both good electronic design and forward error corrections, the communication channels are not entirely safe. In this regard, other safety practices involving hardware-based and software-based techniques are required to limit the impact of electromagnetic disturbances on safety-critical or mission-critical systems in harsh environments.