Selection of cables and connectors for 100BaseTX Ethernet for defense/aerospace environment EMI compliance

100BaseTX Ethernet is a popular method of high-speed data transfer using copper wire in the residential, commercial and industrial environments. Through proper circuit design and printed wiring board layout, IEEE 802.3 100BaseTX Ethernet systems can be made to comply with the applicable FCC Part 15 class B radiated emissions requirements and the European Union´s radiated and conducted immunity EMI compliance requirements using unshielded twisted pair wiring. Because of the tremendous off-the-shelf availability of hardware and software, there are many advantages to using 100BaseTX Ethernet on defense/aerospace platforms to quickly and cost effectively increase system capability. This paper provides methods of determining expected emissions and immunity with respect to defense/aerospace equipment EMI requirements when 100BaseTX Ethernet is used with various cable/connector systems. Data and analysis are presented for cable/connector system that will allow various defense/aerospace EMI requirements to be met.