Page 78 - 2020 Interconnect Innovations eBook

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Common Application Issues are Easy to Handle
The issue for aircraft EWIS engineers is how to take advantage of the potential size, weight, and power (SWaP) advantages of an SPE solution while enhancing network performance. The main application point is how to estimate and evaluate the weight advantage of implementing SPE over other copper-based cabling alternatives.
Otherwise, ARINC-854-compliant SPE maintains the performance advantages common to twisted-wire-pair Ethernet cabling. For example:
Bandwidth and Speed: In accordance with the ARINC 854 adoption of 100BASE-T1 specifications, a compliant SPE interconnection system will be qualified for 200MHz and 100Mb/s operation at 15m (49ft) link lengths. Anticipating further development of ARINC standards as future market needs emerge, at least one manufacturer’s product roadmap envisions support for 1Gb/s and 10Gb/s data speeds, links up to 40m (131ft) long, and frequencies over 750MHz. This roadmap also includes new connector designs to accommodate higher frequencies and speeds and already foresees 1000BASE-T1 SPE for aerospace over longer run lengths.
Signal Integrity: ARINC-854-conforming SPE links have passed 100Mb/s testing over a total of six connections and passes. Impedance, propagation delay, insertion loss (IL), return loss (RL), and longitudinal conversion loss (LCL)/ longitudinal conversion transfer loss (LCTL) all comport with 100BASE-T1 requirements.
Crosstalk: The configuration of SPE’s twisted-wire-pair cables inherently minimizes crosstalk, providing the same crosstalk noise reduction properties common with 100BASE-T1 links.
EMI: Immunity to electromagnetic interference (EMI) also aligns with 100BASE-T1 specifications.
Lightning Strikes: Along with supporting standard electrical signal characteristics, an aircraft interconnect system must also deal with lightning strikes as part of their performance requirements. Qualified SPE systems are capable of withstanding typical strikes up to 3.6kA.
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» TE Connectivity’s Mini-ETH Single-Pair Ethernet System for aircraft designs are specified in the ARINC 854 standard and enable Ethernet transmission with just two wires, rather than eight, providing significant size, weight, and performance advantages.