The Avionics Landscape: A Shift Towards Ethernet Converters for Legacy I/O

https://www.aerospacedefensereview.com/alta-data-technologies/

Modern avionics systems are increasingly dominated by Switched Ethernet, a testament to its flexibility and performance. However, this shift presents a significant challenge: how to seamlessly integrate vital legacy communication standards—such as MIL-STD-1553 (1553), ARINC 429, and discrete I/O—that remain critical for operations like radio, flight controls, and stores management.

A flexible and cost-effective approach has taken hold: directly connecting these legacy I/O sources the Ethernet network via small, portable data converters or collectors. This “appliance” or “brick” approach effectively transforms the Ethernet network into a pseudo-backplane, utilizing small, rugged bridge devices or in-line cable assemblies. The benefits include near-limitless software portability (as almost every operating system supports Ethernet “sockets”), simplified hardware configurations, reduced power consumption, and simplified wiring.

Alta Data Technologies: Pioneering Networked I/O Solutions

At the forefront of this evolution is Alta Data Technologies (Alta). Recognizing the transformative potential of networked I/O over 10+ years ago, Alta pioneered the concept of real-time 1553 & ARINC converters with their groundbreaking ENET-1553™ product.  The ENET is a real-time avionics Ethernet converter that seamlessly bridging legacy 1553 systems in a rugged package about the size of a candy bar.  Figure 1 shows an ENET in an Ethernet configuration.

Figure 1: Simplified Concept of Avionics Ethernet LAN with Real-Time I/O Converter ENET-1553

Alta’s design ingeniously utilizes a thin-server, real-time IP/UDP protocol engine as its “backplane,” that allows memory at speeds approaching traditional PCIe backplanes. The thin-server methodology is a game-changer, significantly shortening round-trip transmission times by optimizing IP/UDP stack processing.

Understanding the Nuances: Beyond Raw Speed

While Ethernet boasts significantly higher bit-rates (e.g., 1000 Mbps) compared to legacy standards like MIL-STD-1553 (1 Mbps), raw bit-speed alone doesn’t tell the whole story. The critical command-response timing of 1553 (4-12 microseconds) and its frequent transmission of short, asynchronous packets (often 2000+ per second) can place substantial IP stack processing demands on the client/host computer. Path delays caused by the host’s packet processing can cancel out the significant raw speed advantage of Ethernet compared to legacy protocols like 1553

 

Introducing the NLINE™ Series: The Pinnacle of Rugged Reliability

Building on years of experience and market feedback, Alta engineers developed the NLINE™ product line—an even more ruggedized derivative of the ENET concept. As Jake Haddock, CTO of Alta, explains, “The ENET distinguishes itself with a real-time, FPGA Ethernet IP processing engine in front of our 1553 or ARINC protocol engines. Ethernet IP packets are turned around in less than 10-20 µSec, which is usually much faster than even RTOS IP stacks can process packets at 1G – so our product is not the diminishing variable in the connections path delay.”

However, Alta recognized that a single package couldn’t meet all deployment needs. Haddock elaborates on the NLINE’s development: “For the NLINE product line, we finally settled on a packaging technology that would over-mold the ENET electronics with multiple molding layers, including a copper sheeting layer for EMC requirements. Our NLINE 1553 product passes MIL-810G shock & vibration, MIL-461 EMC, 60,000 ft altitude, and even full operational water immersion, and is available with standard or 38999 connectors.”  Figure 2 shows an NLINE-E1553 cable bump.

Figure 2: Alta’s NLINE Small, Rugged 1553-Ethernet Converter

The NLINE product line further enhances flexibility by offering USB or Thunderbolt™ host interfaces in addition to Ethernet, supporting the same software from lab to deployment.

Alta’s ENET-1553 & NLINE: Robust, Versatile, and Field-Proven Solutions

Alta’s ENET and NLINE products are offered with standard 5-30 Vdc, MIL-704 raw aircraft or Power Over Ethernet (POE) powering options.  The latter reducing cabling requirements.  In addition, all products offer:

  • Automatic Data Bridge Mode: Provides real-time Ethernet conversion of 1553 or ARINC data with IRIG or PTP time stamping.  Allows select packets of data to be shared between networks.
  • Signal Capture: Capture the raw 1553 or ARINC signals for integrity analysis.
  • Automatic Image Loading: Simplifies 1553 setup with fast start-to-ready times.

Alta products are ideal for a vast range of 1553 BC, RT and BM simultaneous system applications, including stores management, power controls, maintenance data logging, and data loaders (memory loaders). Crucially, its’ IP/UDP socket communication is natively supported by virtually every OS, ensuring unparalleled software portability and allowing processing computers to be upgraded independently of the I/O interface.

Alta: The Supplier of Choice for Modern Avionics

With thousands of units deployed on C-130s, Blackhawk Helicopters, and drones worldwide, Alta’s ENET and NLINE products are field-proven and trusted. Rigorously tested to various MIL and DO standards, these solutions are part of a broad portfolio including PCI Express, PMC, and XMC interface cards and USB/Thunderbolt appliances. Most products, including extended temperature variants, are off-the-shelf in 2-4 weeks, and include an industry leading 5-year warranty.  See how the next generation of avionics is evolving at  www.altadt.com